Mass-specific surface area

Sm Mass specific surface area of bulk material m2/kg... 

For example, particles can be photographed and the area of the particle projection can be measured. The equivalent diameter of a hypothetical sphere with the same projection area can then be calculated (Figure 21). In similar ways, other equivalent diameters can be determined such as diameters equivalent to spheres with the same volume, mass, specific surface area, sedimentation velocity in gases or liquids, etc. Sometimes, equivalent diameters are not unequivocal and may be limited in validity by the assumptions on which the physical models are based. 

Depending on the specific surface area the aerosil particle diameter is 5-50 nm [30]. Thus, from the geometric dimensions of particles one can calculate the molecular mass, specific surface area of aerosil, and concentration of surface Si atoms in one particle. Let us use the notation given in [24] nt = full number of silicon atoms in a particle, rig = number of silicon atoms on the particle surface, d = diameter of the particle, p = density of silica, 2.2 g/cm . 

From Greek Bauxite Properties y-form, 0.28% Na2O by mass, specific surface area 122.5 m-/g [917]. 

Properties Cryptomelane, 57.2% Mn, 7% K by mass, specific surface area... 

Properties Contains 7.1% O and 0.5% Cl by mass, specific surface area 36 mVg, mean grain size 15—30 nm, XRD pattern, TEM image available [2515]. 

AI2O3 (Mass"/.) Specific Surface Area (m /g) Electrolyte... 

As diseussed in Referenee 1, it is well documented that, with our standard nanostmetured support partieles, the baseline pure Pt catalyst has a mass specific surface area of about 7 m /g. For our standard loadings of 0.22 mg/cm, this corresponds to an effective surfaee roughness factor (or SEF, surface enhancement factor) of 12-15 cm /cm. Figure 2 shows duplicate measurements (Series A, Series B) of the SEF for the PtAB-2 ternary catalyst at three different loadings eompared to the standard Pt at 0.22 mg/em. It is seen that the ternary has the same surface area with half the amount of Pt as the standard pure Pt catalyst. This doubling of the mass... 

Powder Chemical structure (mass%) Specific surfac area(m g )... 

Ni (0) catalyst can be produced with the aid of plasma. The activation energy of hydrogen production from sodium borohydride with this catalyst system was calculated as 51.35 kj moT With this approach the mass specific surface area can be increased from 0.0063 m g to 23.11 m g without the crystal structure deteriorating. The reason is thought to be the higher resistivity of plasma treated Ni to aggregations. Plasma treatment can enhance... 

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