Porosity interparticle

At 9 hours of immersion, instead, isotherms do not show the pore filling associated with mesopores, which in turn appears again between 25 and 26 hours. After 28 hours of soaking, no mesopore filling is observed (figure 3). The DFT pore size distributions also confirm the presence of mesopores (around 2.2 nm) only at 2 hours of immersion and between 25 and 26 hours. The peak at around 5 nm is probably due to the textural interparticles porosity (figure 3 inset). 

The small, spherical particles of ferrihydrite often pack together to form aggregates >0.1 pm across. The aggregated structure and interparticle porosity create difficulties in measurement of surface area because the internal area is not fully accessible to all measurement techniques. It is rare for more than two methods of area measurement to have been applied to the same sample. Pyman and Posner (1978) obtained an area of 250 m g" using both N2 and water BET measurements. With the EG ME method, however, the same sample had an area of 600 m g". These... 

Mechanical stability ofhexagonal and cubic MTS was investigated as follows 0.2 g of the samples were compressed in a steel die of 2.5 cm2 using a hand-operated press, for 1 min under air. Compressing the powder for longer time (during 1 h) had no further effect on the pore volume, the surface area, the pore size and the X-ray diffraction pattern. Only the interparticles porosity was sligthly affected. 

The pore volume and the surface area of the cubic MTS decreased slowly under pressure as shown in Figure 4 and Table 1. This decrease was slightly larger than for the hexagonal MTS. For the cubic MTS, less interparticles porosity was observed during compression. By SEM analysis the particle size was found to be around 5 pm larger than for hexagonal MTS. The... 

If we express the free cross-section of the column bed by the interparticle porosity (knowing total porosity of packed beds with porous particles is larger because of intraparticle space), we can obtain the true average fluid velocity, v,... 

A comparison of true particle density, apparent particle density, and bulk density can provide information on total porosity, interparticle porosity, and intraparticle porosity. Methods include true particle density measurements via helium pycnometry, mercury intrusion porosimetry, and poured and tapped bulk density. 

In case of constrained swelling, the potential of interlayer porosity change turns out to be swelling pressure owing to the further swelling compaction effect. The effective void ratio (interparticle porosity) decreases with the increase of the moisture content, hence results in the decrease of the bentonite permeability. 

The interior of a reactor is represented by a random-close arrangement of hard impermeable spherical catalyst particles packed in a confining cylindrical container (Fig. 5.24). The radial-distribution function of interparticle porosity shows... 

The range for the interparticle porosity listed in Table 3 is largely based on data from Reference 34. It was found that GFC columns packed with spherical particles have interparticle porosities ranging from 0.35 to 0.39, but columns packed with irregular particles showed values as high as 0.47. These... 

Where Ez is the axial dispersion coefficient, v, is the fluid velocity, is the interparticle porosity, and Re is Reynolds number. 

Given the size of clay particles (10-1,000 nm), they are found in solution as colloidal dispersions or gels. At low water content, they can be obtained as dry powders, and can form solid porous materials upon compaction. In all these regimes, their properties crucially depend on the charge density and on the nature of the counterions. Most counterions are mono- or divalent, usually alkaline (most commonly sodium Na" or potassium or alkaline earth cations (most commonly calcium Ca " ). They are not incorporated in the clay layers. Rather, they are located near the surface, either between different layers, in the so-called interlayer porosity, or on the external surfaces of clay stacks (typically 10 layers). Such stacks are called particles, and their assembly to form a porous material then leaves voids called interparticle porosity, with sizes between a few nanometers to tens of nanometers, which are usually saturated by an electrolyte solution. 

CNTs and graphene are inherently exohedral carbons which have, in case of graphene only and in case of CNT mostly, an ion accessible onter snrface. This is in contrast with, for example, AC, where almost the entire surface area is within the particles in the form of internal porosity. However, even when composed of ID (CNT) or 2D (graphene) nanomaterials, the resulting CDI electrodes are still by nature three-dimensional and will also have a significant interparticle porosity graphene flakes may also be wrinkled to form sUt pores even within one sheet. Also, the presence of metal catalysts in the CNT material may be a detriment to the EC stability of the resulting CDI electrodes and parasitic side reactions can occur. 

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