Membrane electrochemical parameters

The composition and structure of the coating membranes can easily be modified through control of the chemical and electrochemical parameters of the electrolytic bath. This allows model studies of the response mechanism. 

Vazquez, MI de Lara, R Galan, P Benavente, J. Modification of cellulosic membranes by y-radiation Effect on electrochemical parameters and protein adsorption. Colloids and Surfaces A Physicochem. Eng. Aspects, 2005, 270-271,245-251. 

Ariza, MJ Canas, A MaUeito, J Benavente, J. Effect of pH on electrokinetic and electrochemical parameters of both sub-layers of composite polyamide/polysulphone membranes. Desalination, 2002, 148,377-382. 

Benavente, J Canas, A Ariza, MJ Lozano, AE de Abajo, J. Electrochemical parameters of suUbnated poly(ether ether sulfone) membranes in HCl solutions determined by impedance spectroscopy and membrane potential measurements. Solid State Ionics, 2001, 145, 53-60. 

On one hand, the term characterization is related to pure and basis material questions by investigating physical and chemical parameters like viscosity of inks [1] needed to coat catalysts on membranes or gas diffusion layers (GDLs). Or it can be related to electrochemical data of fuel cells (FC) components like the determination of the ion conductivity of membranes [2-5]. It is obvious to the reader that a really large variety of different characterization methods exist in order to determine several physical, chemical, and electrochemical parameters of fuel cell components. 

Rubio, M. A., Urquia, A., Kuhn, R. et al. 2008. Electrochemical parameter estimation in operating proton exchange membrane fuel cells. Journal of Power Sources 183 118-125. 

Another electrochemical parameter of interest determined from membrane potential results is the membrane permselectivity, S(i), which is a measure of the selectivity of counter ions over co-ions in a membrane [39] ... 

Sensors for measurements of physical parameters such as pressure, rotation or acceleration are commonly based on elongation or vibration of membranes, cantilevers or other proof masses. The electrochemical processes used to achieve these micromechanical structures are commonly etch-stop techniques, as discussed in Section 4.5, or sacrificial layer techniques, discussed in Section 10.7. 

Receptor Action In Analytical Membranes. This work has Identified the Importance of some of the relevant parameters associated with organized lipid matrix ion conduction. Receptors embedded In these matrices should function to perturb one or more of the three compartmenta 1 zones of the BLM. A number of features significant to electrochemical receptor operation follow ... 

The theoretical characterization of the response of this kind of membrane systems in electrochemical techniques is very interesting for determining thermodynamics and transport parameters of ions. 

Tazi, B. Savadogo, 0., Effect of Various Heteropolyacids (HPAs) on the Characteristics of Nafion HPAS Membranes and their H2 /02 Polymer Electrolyte Fuel Cell Parameters. Journal of New Materials for Electrochemical Systems 2001, A, (3), 187-196. 

The magnitude of the proportionality constant L is an indicator of the permeability of the membrane for the solute in question. Experimentally, we can manipulate this parameter, for instance by the addition of specific ionophores. Thus, uncouplers of oxidative phosphorylation increase the permeability of a membrane for ions, while valinomycin increases the permeability for ions. Addition of these ionophores will increase the flux of the respective ions (at equal electrochemical potential gradient) and, therefore, increase the dissipation of their gradient. 

Membrane potential and pH gradient are always determined separately. Since a membrane potential is a delocalized parameter for a given membrane, it follows that the membrane potential generated by the translocation of protons across the membrane will be felt by all ions distributed across the membrane. If an electrical uniport pathway exists for one of these ions, then it will tend to come to an equilibrium when its electrochemical potential gradient is zero ... 

B. Tazi and O. Savadogo. Effect of various heteropolyacids (HPAs) on the characteristics of Nafion(R)—HP AS membranes and their H-2/0-2 polymer electrol3de fuel cell parameters. Journal of New Materials for Electrochemical Systems 4, 187-196 2001. 

Parameter Correlations for A Multicomponent Transport Model for Chlor-Alkali Membrane Cells," Presention at the 157th Meeting of the Electrochemical Society, St. Louis, Mo. 5-11, 16, 1980, Olin. 

Similar to time-resolved spectrometry through which the transient molecular rection can be observed optically, the dynamics of modified or unmodified BLMs, or reconstituted bioreaction on a BLM, can be studied electrically by CV technology where the capacitance, resistance, membrane potential, and current peak are the fundamental parameters in determining the static or the dynamic change in the BLM system. Among these studies, the formation of a s-BLM is valuable in analyzing BLM mechanics and further electrochemical reactions thereon [34,35]. 

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