Encapsulation techniques

Major categories of industrial waste solidiflcation/stabilization systems are cement-based processes, pozzolanic processes (not including cement), thermoplastic techniques, organic polymer techniques, surface encapsulation techniques, and self-cementing techniques (for high calcium sulfate sludges). Vitrification (discussed previously) can also be considered a solidification process. 

C.K. Shaab et al, Microencapsulation of Selected Flare Materials (U) , National Cash Register Co and Illinois Institute of Technology Research Institute for Air Force Avionics Laboratory, Technical Report AFAL-TR-68-25 (March 1969), AD-500878 [Secret report, sections on encapsulation techniques unclassified]... 

Because most food matrices are water soluble, many efforts were directed to the formulation of lipophilic pigments (mainly carotenoids) into water-soluble formulations (powders or gels). For hydrophilic pigments like flavonoids, polar dried microcapsules are the most popular ways to stabilize their functionality. Extracts rich in P-carotene were encapsulated using three different encapsulation techniques (spray drying, drum drying, and freeze drying)." ... 

In general, single molecule encapsulation techniques could provide integrated biogenic materials for the isolation and stabilization of functional bio-nanostructures. 

Special encapsulating techniques have been conceived for physical measurements of actinide containing samples. 

A number of studies have therefore been devoted to the surface states of NC phosphors. Chen et al. (6) recently reported that the principal adsorption band of ZnS at 500 nm becomes more intense and exhibits a blue shift with decreasing particle size from 2.3 nm to 1.2 nm. They attribute these results to the surface states, which are size sensitive. By using the micelle-encapsulation technique, it is possible to link desired chemical species preferentially to the surface. This enables the control of surface concentration, surface structure, and isolation of molecular particles at the same time (7). 

Retardation of release of functional ingredients. Since most of the biofunctionals express their functionality after passing the oral cavity, emulsion and encapsulation techniques are a perfect delivery system for food applications. Important aspects of this approach are stability and the beneficial combination with flavour systems. 

The spray-dried flavours or powder blends are processed by a roller compactor into lumps (Fig. 21.12). These lumps are crushed into granules. This process cannot be categorised as a direct encapsulating technique, since the flavour-encapsulating effect of compacted flavours is based on the use of spray-dried raw material. 

Forty-five hundred pound batches, each, of modified Compn A-3 using the three different waxes were prepd. It is significant that the method used in their production was by an emulsion encapsulation technique. As part of this program, 400 each 105mm HEP-T M393 rounds were loaded and ballistically tested against standard Compn A-3. As a result, Compn A-3 made using AC-656 polyethylene was selected for further evaluation. All acceptance and safety certification tests were successfully completed. It is concluded from the evaluation of the materials produced that ... 

The most recent method of coating RDX is with the emulsion encapsulation technique (Refs 103, 104, 109 111). The process involves essentially the following steps ... 

Containment Behind a Barrier Cells can be immobilized within micro-capsules that have either a permanent or nonpermanent semipermeable membrane. The advantage of encapsulation techniques is the large surface area for contact of substrate and cells. The semipermeable membrane also selectively passes only low-molecular weight components. 

Encapsulation type The type of encapsulation technique (e.g., auger, vacuum, dosator) required for the formulation needs to be determined and justified. Examples are... 

One of the key factors in biosensor design is the immobilisation technique used to attach the biorecognition molecule to the transducer surface so as to render it in a stable and functional form. The challenge is to have a stable layer (or layers) of biorecognition molecules that do not desorb from the surface and that retain their activity. Entrapment or encapsulation techniques avoid the chemical changes that usually change the structure of the enzymes and modify their recognition capacity. 

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