Particle surface area and

Airstream neutralization of acid aerosols by NH3 present in the airway-lumen reduces the health risk associated with acid particles by reducing the acid concentration prior to particle deposition.- In addition, the liquid lining of the respiratory tract probably acts as a chemical buffer," further reducing the health hazard posed by inspired acid particles. Principal factors controlling airstream neutralization of acid aerosols, which is considered to be a diffusion-limited process, are particle surface area, and particle... 

Ap is the particle surface area and therefore the effective diameter becomes... 

Body, J.E. Persson, P. Sjdberg, S. (2000) Benzene carboxylate surface complexation at the goethite (a-EeOOH)/water interface. III. The influence of particle surface area and the significance of modelling parameters. J. Cod. 

Hargrave, B.T., 1972. Aerobic decomposition of sediment and detritus as a function of particle surface area and organic content. Limnol. Oceanogr., 17 583-596. 

Another way of disappearance of nonequilibrium charge carriers is their recombination at the particle surface (radiative with the rate constant ks>r, and nonradiative with the rate constant ks>n). Of basic importance is the question of whether the surface recombination sites are the sites of the quencher adsorption. In other words, is the quencher adsorption able to result in disappearance of the surface recombination sites. With positive answer, the expression for the surface recombination rate should be written as (k + ks,n)-S-(l - 0a)-e-h, where S is the particle surface area, and 0a is the surface fraction occupied by the quencher (electron acceptor). Otherwise, the latter multiplier (1 - 0J should be excluded. Further we will consider the both cases (1 and 2), compare them with experimental data and choose the case providing a better description of the phenomena observed. 

By injection of refractory powders into RF discharges, it is possible to heat treat the particles. Decomposition, vaporization, melting, or surface modification of particles can be achieved in varying degrees depending on the physical properties of the material, particle residence time, particle surface area, and the enthalpy available in the plasma. 

Interphase Interaction. Phase separation in this system is fairly complete, as demonstrated by both electron microscopy and the dynamic mechanical spectra. Nonetheless, interaction is consistent with the extent of separation of the tan 5 peaks, taken as a measure of Tg separation. Inspection of the data in the Tables shows that the greatest reduction in Tg separation occurs in the xx series, that there is some reduction in all series at the longest irradiation delay times, and that there is greater reduction with increasing proportions of PBMA in the mixtures. The changes with increasing delay time are fairly smooth. From the electron micrographs, total particle surface area and the proportion of fine particles increases with increased delay time in all series. 

The presence of physiological surface-active agents in the stomach and small intestine will influence the solubility and the dissolution of sparingly soluble drugs by improved wetting of solid particle surface areas and by micellar solubilisation. This has been reviewed in more detail by Gibaldi and Feldman (1970) and Charman et al. (1997). 

The release of contaminants from a solid into solution involves a number of interrelated mechanisms. Dissolution from solid to liquid occurs at the interface between the particle surface and the liquid passing over it. The overall surface area to mass or volume ratio and the intimacy of contact between the particle surface area and the liquid depend on the particle size and shape distribution and the pore structure of the solid matrix. 

Several aerosol properties depend on the particle surface area and volume distributions with respect to particle size. Let us define the aerosol surface area distribution ns(Dp) as... 

The quantity of bound organosilane correlates with carbon black particle surface area and level of oxygen-containing functional groups. 

Particle surface area and other properties versus particle size. 

It is found that the etching rate increases with the conductivity and storage capacity of the carbon, particle surface area and concentration, spraying pressure and temperature, and the process is also catalysed by the presence in solution of a soluble redox species. Hence the process solution generally contains 30 g 1 of ferric sulphate. 

Figure 28.28 Correlation of (a) the particle extinction coefficient at 308 nm, (b) the back-scatter coefficient at 308 nm, (c) the extinction-to-back-scatter DIAL ratio, (d) the effective radius of the particle size distribution, (e) the particle surface-area and (f) the mass concentrations the data were recorded on 4 April 1992. The lidar signal profiles are smoothed with a height window of 600 m for the back-scatter coefficient and 2500 m in all other cases the error bars indicate the overall retrieval error. The optical depth of the stratospheric aerosol layer was 0.25. The dashed line indicates the tropopause. Adapted from Ansmann et al, J. Atmos. Sci., 1997, 54 2630, with permission ofthe American Meteorological Society...

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