Weight average particle size

The following equation relates the interparticle distance (ID) to the volume fraction of the impact modifier (4)) and the weight-average particle size (dlT) [28] ... 

Composition Component % by weight Average particle size... 

It would appear then that the results of Smith and Mapstone (19), where simply —200 mesh coal instead of a specific screen cut was used, are meaningless. For, presuming that reaction is mostly on the external surface of the coal particle, it is impossible to determine the reactivity of their coals unless one makes the rather stringent assumption that all coals when pulverized to —200 mesh have the same weight average particle size. Fortunately, in all other papers on the rate of a liquid phase oxidation as a function of rank, specified average screen cuts of 80 or larger mesh were used. Hence, reactivities can be calculated directly from the reaction rates reported in the papers, and Equation 4 can be used to compare the results of the different papers. 

One last note about particle size it is an average size of a very wide range, from 1 to over 1000 pm. The number used per Eqs. (4.14) and (4.16) is a representation of the weighted average particle size and is a referenced data source per viscosity of the media in which the particle rises or falls. 

Analyses of covariance for both turbidity weight-average particle size (Dw) and polydispersity (Dw/5n) (Dn, number-average particle size) were carried out. The Tables I and II show the results for the three samples combined. 

Figure 5. Apparent Weight Average Particle Sizes of PMMA Latexes - SFFF vs DCP ...

Effective crystal radius, cm Number average particle size, cm Weight average particle size, cm Intracrystalline diffusivity, cm /sec... 

Two typically employed average particle sizes are the arithmetic average particle sizexi o = o [e.g., for a number distribution (r=0) obtained by counting methods], and the weighted average particle size Xi r = Ml r [e.g., tor a volume distribution (r = 3) obtained oy sieve analysis], where Xi r represents the center of gravity on the abscissa of the qr(x) distribution. 

The structural analysis of the blends and the deformation layer was performed with scanning electron microscopy (SEM) on cryomicrotomed samples. The weighted average particle size (dw = Xn f/Sn,, where n is the number of particles and d is diameter) was determined from the micrographs with a particle-size analyzer (Zeiss TGZ 3). Transmission electron microscopy (TEM) was performed on microtomed samples that were stained with Os04 for 24 h at room temperature before being cut. The thin slices were then stained again for 48 h at room temperature and studied with a JEOL 200 CX instrument. 

Fig. 11.25 Temperature of brittle-tough transition as a function of the weight-average particle size for blends of PA6 and 10 wt.% rubber, with different types of rubbers , EPDM -h, EPR X, LDPE A, Keltaflex ...

Calculate area-weighted average size L3 2- As shown in Examples 10.6 and 10.7, the area-weighted average size equals M3/M2. However, for an MSMPR, the area-weighted average particle size also happens to equal 3Gr. Thus, L3 2 = 3(3 /zm/min)(33.4 min) = 300 p,m. 

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