Self-organization with traveling waves: A case for a convective torus

A traveling wave of BaSO4 in the chlorite-thiourea reaction has shown concentric precipitation patterns upon being triggered by the autocatalyst HOCl. The precipitation patterns show circular rings of alternate null and full precipitation regions. This self-organization appears to be the result of the formation of a convective torus. The formation of the convective torus can be described as a Benard-Marangoni instability with lateral heating

A synthetic method for judging the validity of a CFD tool applied to axial flow cascades

An experimental validation-based method is presented for qualification of CFD tools modelling stationary linear blade cascades. The method gives an aid on how to weight the discrepancy between certain measured and computed quantities when qualifying a CFD tool. The discrepancy between measured and computed data on each elemental cascade is expressed with a single quantitative indicator. This indicator has been derived on a theoretical basis making relationships between blade section lift and drag coefficients in the stationary linear cascade as well as the aerodynamic performance of a corresponding 2D elemental annular cascade in a shrouded isolated rotor. The application of the qualification method is demonstrated in case studies involving blade cascades with sweep and dihedral

On the traces of absolute enantioselective synthesis

The main goal of this communication is to show the utility of empirical approaches combined with mathematical methods in the research regarding the molecular basis of biological chirality. Preparative results (enantiomeric excesses, e.e.) obtained in asymmetric autocatalysis with (AAC) and without (AES) chiral additive were analyzed. Statistical calculations show, that AES (absolute enantioselective synthesis) experiments yield two independent groups of results with prevalence of the R- or S-enantiomer. These are distributed asymmetrically in a second-order beta distribution. Empirical calculations both on AAC and EAS enable to identify the very low (statistical) e.e.-s amplified by AES. These initial e.e.-s show normal distribution. Possible molecular-level reasons of these results were controlled by quantum chemical MO calculations and compatible mechanism(s) are discussed