Peanut-type particles

Shindo.D., Park, G-S,WasedaY Sugimoto,T. (1994) Internal stmcture analysis of monodis-persed peanut-type hematite particles produced by the gel-sol method. J. Coll. Interf. Sci 168 478-484... 

Sugimoto, T., K Sakata, A. Muramatsu (1993) Formation mechanism of monodisperse pseudocubic a-Fe203 partides from condensed ferric hydroxide gel. J. Colloid Interface Sd. 159 372-382 Sugimoto, T. Khan, M.M. Muramatsu, A. Itoh, H. (1993) Formation mechanism of monodisperse peanut-type a-Fe203 particles from condensed ferric hydroxide gel. Colloids Surfaces A 79 233—247. 

Fig. 1.3.10 SEM images of (a) pseudocubic, (b) ellipsoidal, (c) peanut-type, and (d) platelet-type hematite particles. The particles of (a), (b), and (c) were prepared under the same conditions as those of the particles in Fig. 1.3.7 but with 10-2 and 3.0 X 10-2 mol dm-3 Na2S04 for (b) and (c), respectively. The platelet particles in (d) were prepared by aging a P-FeOOH suspension ( 0.9 mol dm-3) at 70°C for 8 days in a medium of 2 mol dm-3 NaCl and 7.5 mol dm-3 NaOH. (From Refs. 16 and 20.)...

Fig. 1.3.11 Electron micrographs of the Liltrathin sections of (a) pseudocubic and (b) peanut-type hematite particles. (From Ref. 21.)...

As manufactured, PTFE is of two principal types dispersion polymer, made by suspension polymerization followed by coagulation, and granular PTFE, polymerized and generally comminuted to a desirable particle size. Some details are given by Sperati. We have observed cast films of an aqueous colloidal dispersion and see that it consists of peanut-shaped particles, approximately 0.25 pm in size, which are composed of even finer particles. Electron micrographs of as-polymerized granular particles show three structures bands arranged in parallel, striated humps, and fibrils, some of which have the shish-kebab structure."... 

Moving-bed percolation systems are used for extraction from many types of ceUular particles such as seeds, beans, and peanuts (see Nuts). In most of these cases organic solvents are used to extract the oils from the particles. Pre-treatment of the seed or nut is usually necessary to increase the number of ceUs exposed to the solvent by increasing the specific surface by flaking or rolling. The oil-rich solvent (or misceUa) solution often contains a small proportion of fine particles which must be removed, as weU as the oil separated from the solvent after leaching. 

Recently, Miller and Cacciuto explored the self-assembly of spherical amphiphilic particles using molecular dynamics simulations [46]. They found that, as well as spherical micellar-type structures and wormlike strings, also bilayers and faceted polyhedra were possible as supracolloidal structures. Whitelam and Bon [47] used computer simulations to investigate the self-assembly of Janus-like peanut-shaped nanoparticles and found phases of clusters, bilayers, and non-spherical and spherical micelles, in accordance with a packing parameter that is used conventionally and in analogy to predict the assembled structures for molecular surfactants. They also found faceted polyhedra, a structure not predicted by the packing parameter (see Fig. 8). In both studies, faceted polyhedra and bilayers coexist, a phenomenon that is still unexplained. 

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