Fibrillar bundles

On the macroscale gels do not flow and hence a simple test for a gel is to invert its container - if it lands on the floor with a splash it is probably not a gel On the microscale the solid-like component generally comprises fibrillar bundles of high aspect ratio and in the case of chiral gelators can adopt... 

Large crystalline aggregates, called microcrystalline cellulose, are formed after hydrolysis of cellulose with dilute mineral acids (loelovich and Leykin, 2006). The presence in cellulose samples of such diverse structures as fibrillar bundles, lamellas, and layers is also a result of aggregation of smaller nanoscale constituents into larger stmctures. To prevent the aggregation of the isolated nanoconstituents, special technology methods are required. 

The rearrangement of the polymer chains of the as-polymerized sample takes place by annealing at temperatures below the melting point. The annealing effects on the long spacing of 100 A and the melting behavior of poly(tetroxocane) confirm the coexistence of lamellar crystallites which are situated between the fibrillar bundles of the extended chain crystallite. 

Fiber structure, either external, i.e., linear or branched geometry, fibrillar, bundles, etc., or internal, i.e., hollow or plain fiber... 

FIGURE 2.17 Crystalline polymer structures formed under applied tension including flow conditions. The center shows the tertiary monofibriUar structure including platelets, the left shows these mono-fibrillar structures bundled together forming a quaternary structure fibril, and the right shows the distorted shish kebab formed with more rapid flow. 

Fig. 21a—d. Crazes in front ofa crack in bulk, fine-spherulitic PP 1120 loaded at room temperature a general view of a thin section in polarized transillumination b higher magnification of (a) showing the preferred craze paths c SEM-micrograph of the fibrillar structure in the craze bundle as seen on the surface of the bulk specimen d stretched craze matter in the interior after tnicrotoining a 2 mm thick layer from the sinface of a bulk PP specimen... 

Typically the pulp is made in two stages about two-thirds of the energy is applied at the first stage. In the first stage the chips are reduced to fibres or fibre bundles by high eonsistency refining (20-25%). In the second refiner fibre quality is improved and due to the repeated eompression-decompression cycles outer lamellae are stripped from the fibres to give fibrillar fines. 

Pilocytic means composed of hair cells, which is a major feature of the pilocytic astrocytoma. Parallel bundles of elongated, fibrillar, cytoplasmic processes resemble mats of hair (see Fig. 20.12A). These hairlike processes contain large amounts of glial fibrils, which stain well with immunoperoxidase for GFAP (see Table 20.5). 

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