Submicrometer size range

A colloid is a material that exists ia a finely dispersed state. It is usually a solid particle, but it may be a Hquid droplet or a gas bubble. Typically, coUoids have high surface-area-to-volume ratios, characteristic of matter ia the submicrometer-size range. Matter of this size, from approximately 100 nm to 5 nm, just above atomic dimensions, exhibits physicochemical properties that differ from those of both the constituent atoms or molecules and the macroscopic material. The differences ia composition, stmcture, and iateractions between the surface atoms or molecules and those on the iaterior of the colloidal particle lead to the unique character of finely divided material, specifics of which can be quite diverse (see Flocculating agents). 

By a slightly different procedure, Seshadri et al. (25) obtained monodisperse Au particles in the submicrometer size range from reduction of HAuCU in a EG-DEG mixture (pH = 4.5) in the presence of PVP. 

Porstendorfer, J. Mercer, T.T. (1978) Adsorption probability of atoms and ions on particulate surfaces in submicrometer size range. Journal of Aerosol Science, 9, 469-74. 

The X-ray disc centrifuge is a centrifuge version of the gravitational instrument and extends the measuring technique well into the submicrometer size range (ISO 13318-3 2004, Part 3 Centrifugal X-ray Method). 

The capability of FFF to produce high-resolution (and thus detailed) size distribution curves in the submicrometer-size range is particularly important. Submicrometer-size distributions extending down to 5-nm diameter, as obtained from flow FFF, are generally very difficult to obtain by other techniques. For such small particles, electron microscopy is a primary tool, but electron microscopy can be used even more beneficially in combination with FFF, particularly if aggregation or other morphological features of the sample materials must be examined. 

Radke, 1981 Radke et al, 1976). Although these small particles contribute little to the total aerosol number density (see Fig. 7-1), their origin is still undetermined. The problem is that bubbles with radii much smaller than 50p.m dissolve too rapidly in seawater. Blanchard and Woodcock (1980) suggest that the absorption of organic matter onto the bubble surface stabilizes some of the bubbles in the 10 p.m size range and prevents their dissolution. The possibility that these bubbles are responsible for the production of sea-salt particles in the submicrometer size range must be considered. 

Colloidal particles, which are operationally defined as particles having at least one dimension in the submicrometer size range, include the size range of nanoparticles... 

One approach to generate materials with tailored uniform pores in the submicrometer size range is based on the use of specific templates or imprints following biological... 

The DMA was originally intended to be used as a monodisperse aerosol generator to produce submicrometer-sized aerosols for testing and calibration. However, it is used more commonly to measure particle size distribution with high resolution in the submicrometer size range. By monitoring the exit aerosol stream with a CNC (see Section 13.6), the number concentration in a narrow range of mobilities, and thus the particle size, can be determined. The entire submicrometer particle size dis-... 

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