Interpore Spacing

Examples of Pore Diameter, Interpore Spacing and Pore Density of the PS Formed under Different Conditions (a More Extensive List is Given in Ref.1) ... 

The variation of interpore spacing or wall thickness is more complex than pore diameter. There is not much information on the relationship between wall thickness and formation conditions. In general, the walls are on the same order as or smaller than pore diameter.24 In particular, interpore spacing depends on potential it increases with potential at small currents but at certain current it starts to decrease with increasing potential. When interpore spacing is reduced to zero, which occurs in the transition region, pores no longer form, and instead, shallow pits form. 

Pore diameter and interpore spacing are determined by two large groups of factors those that affect carrier density on the surface of a pore bottom and those that affect only the distribution... 

The AAO substrates with uniform and parallel nanoporous structure were prepared in a two-step electrochemical anodization of aluminum foils in 4 % oxalic acid, at the constant current density of 3 A/dm, during 60 min. The pore diameter and average interpore spacing were 40 5 nm and 120 20 nm, correspondingly. The arrays of Ag nanoparticles on AAO were formed by thermal evaporation of silver onto a AAO substrate at room temperature. The mass thickness of silver was varied by varying the deposition time. Two series of samples with thickness 30, 60, 90, 120, 150 and 180 nm were prepared. 

Fig. 3. Schematic representation of a pore space, showing a surface layer h, the pore radius r, and the interpore spacing b.

Fig. 8. Plot of spin-echo intensity (on a logarithmic scale) against the gradient wave vector q for water in a randomly packed bed of polystyrene spheres with average diameter 15.8 pm. The diffusion time A was 20 ms (squares), 40 ms (triangles), 70 ms (circles) and 110 ms (diamonds). A coherence peak is observed at a position corresponding to the average interpore spacing. (Reproduced with permission from ref. 147, 1992, American Institute of Physics.)...

Figure 9.47 The dependence of the type of pore-boundary interaction on microstruc-tural parameters when pores migrate by surface diffusion. The interpore spacing is assumed to be equal to the grain size. (From Ref. 83.)...

Artifacts obtained by reaction bonding in a process known for over 15 years as the REPEL process, which is basically still that developed by British technologists. Green products are pressed from silicon carbide powders usually made by the Aecheson process from silica and carbon heated to in excess of 2200°C, with excess graphite present. Molten silicon then infiltrates the connected pores where, on further heat treatment, reaction with the extra graphite produces SiC in the interpore space. This secondary SiC is referred to as reaction sintered. The final body has about 12% free unreacted silicon. 

---