Granulation variables

Natural gums (acacia, tragacanth) 1-5 Form very hard granules variability in quality... 

Consider first of all the continuous variables, Xj and Xj. The domain is (unusually) cylindrical. It is circular in the granulation variables (X Xj) because the experimental points form a pentagon and cubical in the lubrification time (X,) which takes 3 levels only. The two remaining variables are discrete and treated as qualitative variables. They may take any of the four factorial combinations of the 2 settings available to each factor. The cylindrical domain is therefore repeated 4 times, once for each combination of the fixed values of X, and X4. 

The model was therefore a full second-order model in the granulation variables, but also included a first-order term in the third factor, the type of mixer. In addition there were interaction terms between the type of mixer and all the granulation terms. They also carried out experiments at the 20 kg scale. 

Granulation Rate Processes and Effect of Operating Variables. 20-75... 

Sfo is the Stokes number based on initial nuclei diameter do [Adetayo et al.. Powder Tech., 82, 37 (1995)]. Extent (/cf), depends logarithmically on binder viscosity and inversely on agitation velocity. Maximum granule size depends hnearly on these variables. Also, (/cf ), has been observed to depend hnearly on liquid loading y. Therefore, the maximum granule size depends exponentially on liquid loading. Fig. 20-73 illustrates this normahzation of extent (/cf), for the drum granulation of hmestone and fertilizers. 

Tablet Formulations (Immediate Release). Two papers in the mid-1990s reported the earliest studies on immediate release tablets. In the first, tablet formulations of hydrochlorothiazide [33] were modeled in an attempt to maximize tablet strength and select the best lubricant. In the other, a tablet formulation of caffeine was modeled [34] to relate both formulation and processing variables with granule and tablet properties.

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