Silica Sulphuric Acid as an Efficient Catalyst for the Catalytic and Metal-free Oxidation of Aromatic Amines to their Corresponding Nitro Compounds with Sodium Perborate under Micellar Media

Electron-donating substituted anilines were converted to their corresponding nitro compounds with sodium perborate in the presence of a catalytic amount of silica sulphuric acid under micellar media in moderate to good yields.Keywords: Sodium perborate, nitro compounds, silica sulphuric acid, oxidation of aniline

Oxidation of Alcohols by Ferric Nitrate in the Presence of Barium Chloride or Silica Sulphuric Acid under Mild Heterogeneous Conditions

Oxidation of various alcohols were carried out by the mixtures of Fe(NO3)3.9H2O and BaCl2.2H2O or  Fe(NO3)3.9H2O and silica sulphuric acid under mild and heterogeneous condition with good to excellent yield.KEYWORDS: Oxidation, ferric nitrate, barium chloride, silica sulphuric acid, heterogeneous or solvent-free conditions

Entanglement of electronic subbands and coherent superposition of spin states in a Rashba nanoloop

The present work is concerned with an analysis of the entanglement between the electronic coherent superpositions of spin states and subbands in a quasi-one-dimensional Rashba nanoloop acted upon by a strong perpendicular magnetic field. We explicitly include the confining potential and the Rashba spin-orbit coupling into the Hamiltonian and then proceed to calculate the von Neumann entropy, a measure of entanglement, as a function of time. An analysis of the von Neumann entropy demonstrates that, as expected, the dynamics of entanglement strongly depends upon the initial state and electronic subband excitations. When the initial state is a pure one formed by a subband excitation and the z-component of spin states, the entanglement exhibits periodic oscillations with local minima (dips). On the other hand, when the initial state is formed by the subband states and a coherent superposition of spin states, the entanglement still periodically oscillates, exhibiting stronger correlations, along with elimination of the dips. Moreover, in the long run, the entanglement for the latter case undergoes the phenomenon of collapse-revivals. This behaviour is absent for the first case of the initial states. We also show that the degree of entanglement strongly depends upon the electronic subband excitations in both cases