Diameter surface area median

Example 2.9 Given a lognormally distributed aerosol with a geometric mean diameter of 1.5 pm and a og of 2.3, what are the surface-area median diameter and the mass median diameter of this aerosol ... 

A second comparison can be made if one compares to a still larger aerosol, with a mass median diameter of 20,000nm and a surface area median diameter of 200 to 400 nm (described in Reference 26). In this case, <500 nm would also contain >65% of the surface area available to the lung interstitial space. Since the aerosol in this exposure is only 1440 nm, an even higher percentage of the surface area should be less than 500 nm. Thus, most of the surface area would likely locate in the pulmonary interstitial space. Since TiOa is insoluble, the particles would be expected to persist in that location for some time, and serve as a possible source of irritation, inflammation, and injury. 

Properties Specific surface area, median particle diameter (see Table 3.773). Detailed chemical analysis, particle size distribution, and pore volumes and diameters available [186]. 

Surface area median Jo " ns Dp)dDp = Diameter below which one-half... 

The median particle diameter is the diameter which divides half of the measured quantity (mass, surface area, number), or divides the area under a frequency curve ia half The median for any distribution takes a different value depending on the measured quantity. The median, a useful measure of central tendency, can be easily estimated, especially when the data are presented ia cumulative form. In this case the median is the diameter corresponding to the fiftieth percentile of the distribution. 

Median Diameter. The median droplet diameter is the diameter that divides the spray into two equal portions by number, length, surface area, or volume. Median diameters may be easily determined from cumulative distribution curves. 

Mineral Median Particle Diameter (microns) Surfac Area (meter /gram)... 

This relatively large surface area and the fact that the isotheim is of Type IV indicate that this film has porosity in the mesoporous range. A pore size distribution using the desorption branch of the isotherm is shown in Figure 4.16 (page 190). A fairly unimodal distribution is obtained with a median pore diameter of... 

Median Particle Diameter (microns) % less than 10 microns 15-20 Bulk Density - loose (gm/cm3) 0.9 Bulk Density - packed (gm/cm3) 1.2 Specific Gravity (gm/cm3) 2.42 Surface Area (m2/gm) 2-3... 

The MIP method seems to be the most relevant since, as seen from the results, it provides additional information as for the median particles diameter and Specific Surface Area. 

Properties BET specific surface area 56 mVg [127], 62 mVg [1767], specific surface area 149m7g [186,1766], median particle diameter 15.6 pm, detailed chemical analysis available [186],... 

Properties 99% pure, 1% of mica and quartz, specific density 2600 kg/m , BET specific surface area 24.8m-/g, median diameter 2.8 pm [2257]. 

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