Crystallization of active pharmaceutical ingredient (API) or pharmaceutical drug substances is a crucial unit operation. In this paper challenges and scientific progress over the last two decades in the areas of pharmaceutical crystallization thermodynamics, kinetics, polymorphism, process modeling, and process control were attempted. Effective utilization of such scientific knowledge for optim...

Abstract: In this research work, crystallization kinetics of Fe55Cr18Mo7B16C4 alloy was evaluated by X-ray diffraction, TEM observations and differential scanning calorimetric tests. In practice, crystallization and growth mechanisms were investigated using DSC tests in four different heating rates. Results showed that a two -step crystallization process occurred in the alloy in which - Fe phas...

Kinetics of crystal growth in non-isochemical systems is considered taking into account the changes in composition of the residual melt during the process. This leads to the formation of concentration gradients in the vicinity of the new phase. If a component acting as a network modifier is enriched in the crystalline phase, the melt at the interface is enriched in network formers and the glass...

Metallic glasses are kinetically metastable materials. Metallic glass is defined as “A liquid, which has been cooled into a state of rigidity without crystallizing”. Properties of metallic glasses differ form non metallic glasses. Ordinary glasses are made up of silica while metallic glasses are made of alloy metals. Ordinary glasses are transparent whereas metallic glasses are opaque. In ordin...

Viscosity has been determined during isothermal crystallization of an andesite from Tungurahua volcano (Ecuador). Viscosity was continuously recorded using the concentric cylinder method and employing a Pt-sheathed alumina spindle at 1 bar and from 1400°C to subliquidus temperatures to track rheological changes during crystallization. The disposable spindle was not extracted from the sample but...

Transparent glasses in a system of Li2O-MgO-SiO2-Al2O3-Fchemical constituents were prepared by melt quenching method. In the fabrication of nanocrystal glass-ceramics, controlled nucleation and subsequent crystal growth were necessary to avoid loss of transparency. It was therefore important to understand thermal properties and crystallization kinetic...

Chalcogenide glasses are disordered non crystalline materials which have pronounced tendency their atoms to link together to form link chain. Chalcogenide glasses can be obtained by mixing the chalcogen elements, viz, S, Se and Te with elements of the periodic table such as Ga, In, Si, Ge, Sn, As, Sb and Bi, Ag, Cd, Zn etc. In these glasses, short-range inter-atomic forces are predominantly cov...

Variabilities in polyamide 6 (PA6) composite manufacturing by liquid processes can occur due to polymerization, crystallization, and flow through a fibrous preform. Numerical simulations of the process predicting kinetics facilitate optimization. This study proposes an efficient modeling approach that be integrated current simulation discretization methods such as finite volume method (FVM) whi...

phenomena from solid dispersions with enteric coating agents in JP XI 2nd fluid(pH 6.8). Nifedipine,griseofulvin and spironolactone were used as drugs.The rate of crystallization of all drugs was remarkably inhibited by the presence of CMEC.It was found that the inhibition was not due to solubilization of the drugs by CMEC. The crystallization kinetics from supersaturated solutions suggested th...