An efficient sonochemical route for synthesis of nano sized zinc oxide is reported. The method employs zinc acetate and sodium hydroxide as precursors with isopropyl alcohol as a solvent. As prepared powders were characterized by XRD, SEM and FTIR. These show that the resulting powder is composed of multidomain crystallites of ZnO wurtzite, zincite and Zn(OH)2. The XRD-measured coherent domain size varies from about 20 to 30 nm, whereas SEM exhibits  200 nm crystallites. The wurtzite phase is found to dominate at sonication times smaller than  30 min. It is also found that the powders produced sonochemically exhibit smaller and narrower size-distributed particles compared to that in hydrothermally prepared powders.

The effect of internal and external electron donors on the polymerization of propylene in a liquid monomer or a hydrocarbon diluent (hexane) in the presence of a titanium-magnesium nanocatalyst acti vated with an organoaluminum compound (triethylaluminum, triisobutylaluminum) and the properties of the resulting PP are studied. The polymerization of propylene in the absence of internal and external donors yields atactic PP, whereas, in the presence of a catalyst containing an aryl internal donor, isotactic PP is formed. The activity and stereospecificity of the catalytic system substantially depends on the method of elec tron donor introduction. The thermal treatment of the catalyst with an electron donor affects its activity and stereospecificity.

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