Wurster geometry

In complex organic molecules calculations of the geometry of excited states and hence predictions of chemiluminescent reactions are very difficult however, as is well known, in polycyclic aromatic hydrocarbons there are relatively small differences in the configurations of the ground state and the excited state. Moreover, the chemiluminescence produced by the reaction of aromatic hydrocarbon radical anions and radical cations is due to simple one-electron transfer reactions, especially in cases where both radical ions are derived from the same aromatic hydrocarbon, as in the reaction between 9.10-diphenyl anthracene radical cation and anion. More complex are radical ion chemiluminescence reactions involving radical ions of different parent compounds, such as the couple naphthalene radical anion/Wurster s blue (see Section VIII. B.). 

The methyl groups on the ring in octamethyl-p-phenylene interfere with this interaction by affecting the molecular geometry. Thus there is no resonance stabilization as in the Wurster salt cation and it is not as stable. 

A Wurster coater similar to the equipment of Fig. 7.35 was simulated by DPM. The original geometry and the meshed model are shown in Fig. 7.49. 

To assess the radial distribution of particles in the granulator, horizontal slices were cut out of the simulated geometry. This was done at two different heights, as shown in Fig. 7.51. The thickness of each of the slices is 10 mm. The first slice is situated in the lower part of the Wurster tube, just around the tip of the injection nozzle. The second... 

The complexation with Pt(ll) for traditional crown 22 and Wurster s thi-acrownophanes 23 was investigated by various techniques including H NMR spectroscopy, electrospray mass spectrometry, cychc voltammetry, and single crystal X-ray analysis. The crownophane geometry was proved to form im-stable endocycUc complexes with Pt(II), compared with the traditional nest crown geometry [26]. 

The real coating process in the studied Wurster coater apparatus with the bed mass of 3 kg contains about 21.8x10 particles with the size of 550 im. Unfortunately, the numerical effort for the calculation of the DPM model increases with increasing the number of simulated particles. The DPM model is unable to represent this number of particles, at least with the actually available computing power. However, the number of particles can be reduced by conservation of the particle and fluid dynamics in the simulated apparatus and its real geometry. In this work a scaling approach proposed by Link et al. (2009) and extended by Sutkar et al. (2013) has been used, in which the scahng of the particle size was carried out. Due to the size increase, the adequate properties of sohd and gas phase have been adapted to keep the dimensionless numbers Archimedes At) and Reynolds Re) and the velocities of minimal fluidization and elutriation constant. 

In this contribution, the coating process in the Wurstercoater apparatus produced by Glatt (GPCG 3/5, Wurster 7) has been investigated. In Fig. 15, the geometry of the apparatus is illustrated. 

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