One-pot electrochemical synthesis of fused indole derivatives containing active hydroxyl groups in aqueous medium.

An novel and convenient electrochemical approach was developed for the synthesis of indole derivatives from catechols and alpha-oxoheterocyclic ketene N,O-acetals. This method provides an environmentally benign access to fused indole derivatives containing active hydroxyls and carbonyl under mild reaction conditions.

Synthesis, characterization and thermal sensitivity of chitosan-based graft copolymers.

Novel chitosan-based graft copolymers (CECTS-g-PDMA) were synthesized through homogeneous graft copolymerization of (N,N-dimethylamino)ethyl methacrylate (DMA) onto N-carboxyethylchitosan (CECTS) in aqueous solution by using ammonium persulfate (APS) as the initiator. The effect of polymerization variables, including initiator concentration, monomer concentration, reaction time and temperature, on grafting percentage was studied. XRD, FTIR, DSC and TGA were used to characterize the graft copolymers.

Automatically extracting sheet-metal features from solid model.

With the development of modern industry, sheet-metal parts in mass production have been widely applied in mechanical, communication, electronics, and light industries in recent decades; but the advances in sheet-metal part design and manufacturing remain too slow compared with the increasing importance of sheet-metal parts in modern industry. This paper proposes a method for automatically extracting features from an arbitrary solid model of sheet-metal parts; whose characteristics are used for classification and graph-based representation of the sheet-metal features to extract the features embodied in a sheet-metal part. The extracting feature process can be divided for valid checking of the model geometry, feature matching, and feature relationship.