Image surface porosity measurement

The SEM image sample surface analysis and porosity measurements lead to the conclusion that smaller micro- and mesopores are present on the macropore walls (see Figure 7 and Figure 8). The ASAP analysis made on the unetched samples did not reveal micro- and mesopores with diameter <100 nm - so the surface is relatively continuous and flat (in the ASAP analysis the large pores observed on Figure 6 were not taken into account). 

Fig. 13.11 Surface porosity of conventional ultrafiltration membranes and nanofibrous support (the porosity was measured by electron microscopy images) [11] (Reprinted with permission from Ref. [11]. Copyright 2006, Elsevier)...

Ghasemi-Mobarakeh L, Semnani D, Morshed M (2(K)7) A novel method for porosity measurement of various surface layers of nanofibers mat using image analysis fra- tissue engineering applications. J Appl Polym Sci 106 2536-2542... 

Surface pore diameters were measured by visual inspection of the line profiles of 50 pores of each membrane. All membranes have a wide pore size distribution. The deviation between 20 % and 40% from the average value is noticeable in most cases and is higher for membranes with larger pores (or higher MWCOs). The pore density was obtained by observing several AFM images from different sample areas of the same membrane and counting the number of pores in a unit area. Smface porosity is defined as the ratio of the pore area to the total area of the membrane. The porosity is low and varies between 0.6% and 7%. No relationship between MWCO and porosity was found. 

Figure 3.66 shows the scanning electron microscopic images of the surfaces of the reduced A301 catalysts. The porous skeleton structures and the morphology of the catalysts after reductions can be viewed vividly (see Fig. 3.66). The pore skeleton structures of the particles are commonly expressed by three kinds of parameters Porosity, pore volume and pore diameters. Both the pore volume and porosity of iron catalyst after reduction are calculated by the lattice constants measured by XRD before and after the reduction, as seen in Chapter 7.

Figure 4.3 is of simple models of pore shapes of different sizes containing adsorbate molecules. These models demonstrate that not all of the visualized image or surface area of the porosity can be measured, and as a result, caimot be utilized. Figure 4.3 shows that amounts of adsorbate contained within the porosity need not relate, proportionally, to a surface area. 

The pH-changing AND/OR logic systems with the Reset function were used to control porosity of a polymer membrane deposited on an ITO electrode surface [102]. The pores were open (Figure 18.11a, image (ii)), allowing access of a diffusional redox probe to the conducting support and resulting in a small ET resistance, Rgi, measured by impedance spectroscopy only when the pH was decreased upon... 

Table 2.13 shows results of laboratory measurements and numerical calculations. Porosity and specific surface were calculated from the binary image. 

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