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Compressibility of the powder mixture with calcium hydrogen phosphate dihydrate.
Brejchová, Veronika ; Řehula, Milan (advisor) ; Šklubalová, Zdeňka (referee)
Compaction process can be evaluated with the viscoelastic parameters and with compaction equations too. Viscoelastic paramaters are obtained from test of stress relaxation and force-displacement compression profile. The equation of compaction expreses the dependence of volume, density or height of pressed material on the pressure. With this parameters we are able to define various phases of compaction process, mechanism of this process and to characterize pressed material. This diploma thesis deals with the evalution model granulate, which was made from lactose monohydrate and corn starch with in the addition with calcium hydrogen phosphate dihydrate in the ratio from 10 % to 40 %. The samples were evaluated three-exponentional equation was created in the Department of pharmaceutical technology Faculty of Pharmacy in Hradec Králové. This equation is based on the equation of Cooper and Eaton, but it isn't based on real density and charakterizes individual parametrs. In this thesis, it was found that during the pre-compaction and elastic deformation phases, the parameters A1/A2 and E1/E2 are in decrease, while t1/t2 is in increase. In the phase of plastic deformation parameters A3 and E3 grow. It means that with decreasing reduction of volume, the enrergy is in decrease and the process is...
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