Vapour pressure, cell model

Gas, cells, 464, 477, 511 characteristic equation, 131, 239 constant, 133, 134 density, 133 entropy, 149 equilibrium, 324, 353, 355, 497 free energy, 151 ideal, 135, 139, 145 inert, 326 kinetic theory 515 mixtures, 263, 325 molecular weight, 157 potential, 151 temperature, 140 velocity of sound in, 146 Generalised co-ordinates, 107 Gibbs s adsorption formula, 436 criteria of equilibrium and stability, 93, 101 dissociation formula, 340, 499 Helmholtz equation, 456, 460, 476 Kono-walow rule, 384, 416 model, 240 paradox, 274 phase rule, 169, 388 theorem, 220. Graetz vapour-pressure equation, 191... 

Eamus, D., Taylor, D.T., Maclimis-Ng, C.M.O., Shanahan, S., and De Silva, L. 2008. Comparing model predictions and experimental data for the response of stomatal conductance and guard cell turgor to manipulations of leaf-to-air vapour pressure difference and temperature feedback mechanisms are able to account for all observations. Plant Cell Environ. 31 269-277. 

In this chapter we will firstly present a literature survey on vapour pressure, viscosity and conductivity properties of phosphoric acid with an emphasis on the temperature and composition range relevant for fuel cell applications. In a second part we want to elucidate the physico-chemical interactions of a protic electrolyte like phosphoric acid as a doping agent with polybenzimidazole-type polymer membranes. Literature data on m-PBI and AB-PBI as well as own measurements on Fumapem AM-55, a commercial PBI derivative, will be cOTisidered. On the basis of the observed doping behaviour a model describing the thermodynamics of the adsorption process is presented. 

Vapour pressure osmometry VPO). At present commercially available apparatus for VPO is the Corona molecular-weight apparatus models 114 and 117 manufactured by the Corona Co., which have been produced in the past by Hitachi Co. Ltd Knauer Vapour Pressure Osmometer No. 731.110000 (Dr. H. Knauer Wissenschaftliche Cerate, AG) Jupiter Model 233 Vapour Pressure Osmometer (Jupiter Instrument Co. Inc.) and Gonotec model 070 (Gonotec Gesellschaft fiir MeB- und Regeltechnik m6H). A typical VPO apparatus consists of (1) two thermistors covered with glass, to which solution and solvent drops are attached (2) a cell, the interior of which is saturated with solvent vapour (3) a solvent vessel, placed at the lower part of the cell and (4) an electronic circuit. The instrument is usually thermostatted. 

Argyropoulos P, Scott K, Taama WM. Modelling pressure distribution and anode/cathode streams vapour-liquid equilibrium composition in liquid feed direct methanol fuel cells. Chem Eng J 2000 78 29 1. 

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