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Transmission electron microscopy (TEM), dynamic light scattering (DLS) and high sensitivity differential scanning calorimetry (HS-DSC) were used to characterize the linear copolymers of ethylene and acrylic acid (PEAA) nanoparticles prepared by catalytic polymerization of ethylene and tert-butyl acrylate followed by hydrolysis of the ester groups. The PEAA nanoparticles which dispersed in aqueous media exhibited a remarkable reversible thermoresponsive behavior upon heating/cooling from 25 to 80 degree [Celsius].

Careful control of the temperature and duration of the reaction between titanium tert-butoxide and acetic acid has led to the formation of new polyoxotitanate clusters with 14, 18, and 28 Ti atoms. UV/vis spectroscopy on the [Ti.sub.28] cluster has shown that the optical band gap is blue-shifted with respect to a cluster containing only 17 titanium atoms displaying that the optical properties are heavily affected by the internal structure of the particle than its size.

An efficient and highly sustainable Ullmann-type homocoupling of bromo- and chloroarenes, electron-rich chloroarenes, catalyzed by in situ generated Pd colloids, is carried out in aqueous medium under mild conditions. Glucose is used as a clean and renewable reductant, while tetrabutylammonium hydroxide (TBAOH) has acted as a base, surfactant, and phase-transfer agent, which has created a favorable environment for the catalyst.

A new method is described for asymmetric synthesis of either enantiomer of 2-substituted pyrrolidines from a single starting material. This method is effective for a variety of substrates including aromatic, heteroaromatic and aliphatic substituents and the extension of this method is also used for the formation of 2-substituted piperidines.