Particle size, significance

The climate effects of atmospheric aerosol particles are a matter of continuous interest in the research community. The aerosol-climate effects are divided into two groups The direct effect represents the ability of the particle population to absorb and scatter short-wave radiation - directly affecting the radiation balance. These direct effects depend primarily on the aerosol optical properties and particle number size distribution, as the particle size significantly affects the scattering efficiency of... 

Kobayashi et al. [143-146] have synthesized several types of amphiphilic po-ly(2-oxazoline), 34 and its block cooligomers, 53-55, and applied them to soap-free emulsion copolymerization of styrene and vinyl acetate to produce mono-disperse, submicron-sized latex particles. They found that the particle size significantly depended on the type of macromonomer used and generally decreased with increasing the macromonomer concentration. 

Consider an extrusion-spheronization process study. Is the response (the yield of pellets of the desired particle size) significantly different when the mixing time of the wet powder mass (before extrusion) is increased from 2 minutes to 5 minutes ... 

Fractals refer to broken, nonnatural number dimensions. If one studies the selectivity of ethylene epoxidation as a function of silver particle size (section 3.7) or hydrogenolysis (section 3.2) as a function of platinum particle size, significant changes are found. 

Lung function parameter Particle size Significantly different aerosols... 

Ground-state absorption spectrum for powdered microcrystalline cellulose is also shown in Figure 1. It exhibits R values quite close to unity for visible (Vis) and near infrared (NIR) spectral regions and shows a significative absorption in the ultraviolet (UV). Silica and silicalite also have a reflectance close to unity in the Vis and NIR regions and differ from cellulose by the fact that UV absorption is smaller. In the case of silicas with different porosity, but with the same particle size, significant variations of the reflectance were detected [7]. 

In general, residence times may be regarded as ca. 0.5 s and often ca. 0.25 s (Figures 14.4 through 14.7). Particle size significantly affects rate (Figure 14.8). Various combustion systems may be rate controlled due to the occurrence/onset of the Boudouard reaction ... 

A recent computer simulation study [247] has invoked an intermicellar reactant exchange parameter k which is dependent on the surface film flexibility and the dimer lifetime. Unless one of the reactants is in a large excess, k is supposed to influence the final particle size significantly. In addition, it has also been concluded that the smallest particle size is influenced by an optimum dimer lifetime. 

However, when the mixtures are prepared from raw materials with fine particle sizes, significant deviations from ideal narrow particle size distributions do occur. The scale of mixing may still be large due to agglomerates, even though fine particles are used. Additionally, the resultant powder may have a mixed morphology of equiaxed and acicular particles [60, 61]. The product may also contain a significant... 

Particle size significant compared to space between particles. 

An alternative to screen printing is inkjet printing where nanoliter amounts of an ink are printed onto a support as a single spot. Microsized patterns can be realized by combining spots (pixels). Inks can contain nanoparticles (usually with particle sizes significantly less than 200 nm to avoid obstruction of the nozzle) or precursors ... 

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