Water content effects

Water Content Effect Water and glycerol were combined to prepare reaction mixtures containing 10%, 25%, 50% and 75% water. 

The Water Content Effect on the Glass-Transition Temperature of Low Calory Candy Formulations... 

The diffusivity can be affected by concentration of water, but in most instances the transport of water is sorption limited. The temperature and surrounding relative humidity effects on uptake kinetics are usually more important than the water content effects. 

At the same time, the study of the water content effect in the medium has been performed [127] on a 10% weight polypyrrole in PVC blend. The influence of ferric chloride nature (anhydrous, hexahydrous and anhydrous -F water in the medium) on conductivity has been studied. 

DIELECTRIC RELAXATIONS IN NEUTRALIZED AND NONNEUTRALIZED CHITOSAN THE STRONGER WATER CONTENT EFFECT ON THE a-RELAXATION AND THE GLASS TRANSITION PHENOMENON... 

As seen before, a major difference with respect to biphasic catalysis is the low dependence on substrate solubility in the catalytic aqueous phase as the SAPC reaction occurs at the interface. SAPC is strongly dependent on the water content of the solid support. Two types of water content effects have been reported usually SAPC is efficient over a very restricted hydration range where activity exhibits a clear peak, while only recently a large plateau was observed in a higher hydrahon range. 

Many catalyst layer models have appeared in the literature during the last few years [15, 16, 17, 18, 19,20, 21]. This observation partly explains the complications associated with this topic. Still, much work remains to be completed since many effects have not yet been included, such as proton surface diffusion (outside the ionomer, [22,23]) and ionomer density (water content effect), which effectively and respectively increases/modifies the reactive surface area. The surface-sensitive nature of Pt catalysts on the oxygen reduction reaction rate [24] and electrochemical promotion (a catalytic effect, [25]) represent other examples which can also affect the reaction rate and surface area. All these effects are further compounded by the potential presence of hquid water which effectively modifies the reaction front, access to speeifie eatalyst particles and surface properties. 

Water Content Effect on both the O2 Solubility and Diffusion Coefficient 25... 

Distribution of water around SO3" of each system is essentially the same. This is due to an excess of water in both systems. Concerning the effect of temperature, the H3O diffusion coefficients of Krytox-Silica in Naflon increased until 353 K and then kept constant, whereas the pure Naflon system had a positive slope until 333 K (Figure 9.21a). Concerning water content (Figure 9.21b), the H3O+ diffusion coefficient of 5 wt% of Krytox-Silica in Naflon system was constant beyond 50% water molecules, while in the case of pure Naflon system, the same coefficient was decreasing with a higher slope below that point. This indicates that the selected diffusion coefficients for the 5 wt% of Krytox-Silica in Naflon system are increased from 333 to 353 K and then decreased from 353 to 373 K as a result of the temperature and water content effects, respectively (Figure 9.21c and d). However, the diffusion coefficient of H30 in pure Naflon is mainly influenced by the water content. 

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