Enhanced reactivity of 1-carboxy-2-ethoxy-2-imidazoline,a biotin model,in decarboxylation

1-Carboxy-2-ethoxy-2-imidazoline (1) decarboxylates five times as fast as 1-carboxy-2-imidazolidinone (2) in an aqueous alkaline medium.     

New synthetic reaction by electrolysis. III. α-acetoxylation of sulfide

Sulfides are directly converted effectively to the corresponding α-acetoxy sulfides by electrolysis in acetic acid.     

A new emission band under high density excitation in alkali halides

A new emission band has been found in alkali halides under high density excitation produced by heavy ion bombardments and is suggested to be arised from the recombination of bi-excitons.     

Bidentate amidine ligands for nickel(0)-mediated coupling of carbon dioxide with unsaturated hydrocarbons

Novel bidentate amidines were designed and synthesized as easily available electron-donating N-ligands for Ni0-mediated coupling of carbon dioxide with alkynes or allenes, and high regioselectivity was achieved even for the carboxylation of aryl substituted internal alkynes.     

Clustering and combustion of dilute aluminum particle clouds in a post-detonation flow field

A hybrid two-phase numerical methodology is used to investigate the flow-field subsequent to the detonation of a spherical charge of TNT with an ambient distribution of a dilute cloud of aluminum particles. The interaction of the particle cloud with the contact surface results in Rayleigh–Taylor instability, which grows in time and gives rise to a mixing layer where the detonation products mix with the air and afterburn. At early times, the ambient particles get engulfed into the detonation products and ignite. Subsequently, they catch up with the Rayleigh–Taylor structures, and the vortex rings around the hydrodynamic structures cause transverse dispersion that results in the clustering of particles. Then, the particles leave the mixing layer and quench, yet preserve their hydrodynamic foot print. Preferential heating and combustion of particles occurs due to clustering. A higher initial mass loading in the ambient cloud results in larger clusters due to stronger/larger vortex rings around the hydrodynamic structures. A larger particle size results in the formation of fewer and degenerate clusters when the initial width of the cloud is larger. A theoretical model is used to predict the bubble amplitudes, and are in good accordance with the simulation results. Overall, this study has provided some useful insights on the explosive dispersal of dilute aluminum particle clouds and the gas dynamics of the flow field in the mixing layer.