Pores narrowing

On the other hand, if the pore is large and/or the reaction fast (Ik large), or diffusion slow and/or the pore narrow DR small), the efficiency is small and approaches... 

Tablt I. Some References to Literature on the Pore-Narrowing Effect and the Sorptive Behavior of Microporous Solids... 

The studies of Kiselev and his co-workers particularly exemplify the poremarrowing effect and the role of specific (/. 21, 27) sorbate adsorbent interactions, such as hydrogen bonding, which are not affected by pore narrowing. 

The results prove that functionalization of MCM-41 and anchoring of dye molecules result in a pore narrowing but that a high degree of ordering is being preserved. 

Unfortunately, the Kelvin radius (r ) does not equal the actual pore radius (rp), one would like to measure. This is due to the fact that multilayer adsorption occurs, prior to the capillary condensation, resulting in a pore narrowing. Therefore, if t is the thickness of the adsorbed layer, then rp equals... 

Figure 10.16 Specific surface area vs. diborane loading on silica gel. The pore narrowing contribution to the fail in the surface area dashed line.

Figure 10.18 relative amount of pore narrowing (solid line), pore blocking (dashed line) respectively, with pore diameter. 

Figure 3.1. Schematic of the various stages of pore narrowing and closure by the chemical vapor deposition/electrochemical vapor deposition process [Adapted from Lin etal., 1989]...

A major factor that remains to be the biggest challenge in optimizing the performance of membrane processes in the dairy industry is biofouling, which is caused by specific interactions between the membrane and various proteins, as well as protein-protein interactions that can lead to pore-narrowing or pore-blocking, during the filtration process [40,153,155]. 

Chemical Vapour Deposition (CVD) of microporous silica films with a thickness of about 1.5 pm onto mesoporous glass or y-alumina substrates are obtained by deposition from TEOS-oxygen mixtures at 300-700°C. Pore sizes are estimated to be 0.4-0.6 nm or are virtually absent. CVD techniques may also be useful for repairing residual defects and for pore narrowing. 

G.Z. Cao, H.W. Brinkman, J. Meijerink, K.J. de Vries and A.J. Burggraaf, Pore narrowing and formation of ultra thin yttria-stabilised zirconia layers in ceramic membranes by chemical vapor deposition. /. Am. Cer. Soc., 76 (1993) 2201-2208. 

Numerous small pores, narrow bridges, crescent-shaped voids Pelletized raw mix (Kramer, 1960)... 

Figure 5 (a-d) by the fact that suspension of 8 pm sulfonated PSt microspheres in water deposited in the centre of the top side of the hydrogel flowed through. The captured microspheres are well visible in Figure 5 (b-d). They accumulated at the places of pore narrowing their majority, however, was found on the bottom part of the hydrogel. In such a way, the flow of water suspension of microspheres in the hydrogel was traced. 

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