Cooling injection phase

If the pressure were completely switched off after the injection phase, the molding would detach itself fi-om the wall as it cools. There would no longer be any control over the molding s dimensions. It is easy to imagine the consequences in the example of the CD the surface would become uneven, the scanning by laser would become less reliable-in short, the CD would be utterly useless. 

The preparation of nanoparticles by precipitation from an organic solution is well known from the preparation of polymeric nanocapsules and can also be used for the SLN production. The lipid, drug and the stabilizer(s) are dissolved in a water-miscible organic solvent (e.g. acetone, ethanol) or solvent mixture and this solution is dropped in the stirred aqueous phase that may contain a hydrophilic surfactant. Chen et al. firstly evaporated a part of the solvent mixture at elevated temperature before injection into the cooled aqueous phase under stirring. ... 

Injection molding of thermoplastics involves injecting molten polymer into a mold at high pressure. During the injection phase, the melt material is driven into the mold impression. Upon cooling, the polymer surface tends to replicate the superficial texture of the mold surface. 

Cool on-column injection is used for trace analysis. Ah. of the sample is introduced without vaporization by inserting the needle of the syringe at a place where the column has been previously stripped of hquid phase. The injection temperature must be at or below the boiling point of the solvent carrying the sample. Injection must be rapid and no more than a very few, usuahy no more than two, microliters may be injected. Cool on-column injection is the most accurate and reproducible injection technique for capihary chromatography, but it is the most difficult to automate. 

Another contributing mechanism is the direct cooling of hot propellant surface by contact with the injected fluid. The fluid should cause the decomposing surface to reduce its pyrolysis rate to a point where combustion cannot be sustained. In addition, the presence of water on the surface would obstruct heat transfer from the gas-phase reaction zones to the solid surface, thus augmenting the cooling of the surface. Proponents of these two approaches have correlated the injection data on the basis of mass of fluid required per unit area of surface, but theoretical justifications for the use of this particular correlating parameter have not been presented. 

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