2 research outputs found
Synthesis of New Zinc Phthalocyanine with Block Copolymers in Nanomedicine Applications
No full textAccess full text - https://doi.org/10.1007/978-3-030-31866-6_140Synthetic routes towards new conjugates of hydrophilic zinc phthalocyanine (ZnPc) with N-vinylpyrrolidone (NVP) and acrylic chloride (ClAC), are described. For this purpose, a copolymer of N-vinylpyrrolidone (NVP) with acrylic chloride (ClAC), according to the Friedel-Kravts method, was grafted to the benzene nucleus of zinc phthalocyanine (ZnPc). The paper contains the analysis of polymer analogs of NVP- ClAC-ZnPc with IR and UV-VIS spectroscopies
Validation of a 3D multi-physics model for unidirectional silicon solidification
No full textA model for transient movements of solidification fronts has been added to X-stream, an existing multi-physics simulation program for high temperature processes with flow and chemical reactions. The implementation uses an enthalpy formulation and works on fixed grids. First we show the results of a 2D tin solidification benchmark case, which allows a comparison of X-stream to two other codes and to measurements. Second, a complete 3D solar silicon Heat Exchange Method (HEM) furnace, as built by PVA TePla is modeled. Here, it was necessary to model the complete geometry including the quartz crucible, radiative heaters, bottom cooling, inert flushing gas, etc. For one specific recipe of the transient heater power steering, PVA TePla conducted dip-rod measurements of the silicon solidification front position as function of time. This yields a validation of the model when applied to a real life industrial crystallization process. The results indicate that melt convection does influence the energy distribution up to the start of crystallization at the crucible bottom. But from that point on, the release of latent heat seems to dominate the solidification process, and convection in the melt does not significantly influence the transient front shape. © 2011 Elsevier B.V. All rights reserved
