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A green alternative, based on the use of an efficient and recyclable chiral ketone@SBILC@MWCNT@Fe3O4catalytic system (Y= 35%, S= 100% and ee = 100%), was developed for the asymmetric epoxidation of trans-methylcinnamate to (2R,3S)-phenyl glycidate.

The fast variation of the section and contact characteristics of railway exchangers is a difficult matter for an analytical approach. At the same time, vehicle - railway exchanger system includes multiple contact patches, discontinuities in the contact points evolution and the necessity to compute stresses and deformations. As a consequence of the harrs working conditions in the system there is a permanent concern to improve its performance. The analysis of the state of art in the research indicated the need of a complex theory for the study of the mechanical contact. In the paper, a tridimensional analysis of the vehicle - railway exchanger contact patch is carried out using "Contact" software, based on Kalker's theory. The outcome of the study is the computation of tangential forces, creepage speeds and stresses distribution in the contact patches, in order to elucidate the vehicle evolution during this interaction and the estimation of the running safety.

The wheel-rail contact patch analysis methods are related to the evolution of modern computers. Contemporary computation systems allow the approach of tri-dimensional methods which take into account various contact parameters. With this background in mind, the wheel-rail contact problem is a study under development. The paper proposes a tri-dimensional approach, considering the spin creepage parameters. The spin effect is due to the increase of the wear around the wheel flange and the gage face. At the same time, the spin is influenced by the wheel rolling operating conditions. The paper gives an insight of wear mechanisms analysis, plastic deformation and fatigue phenomenon of the contact patch constituent material.