this study was designed to find which one of the three different presentations, i.e. input, input-output, and output-input, will be more effective in iranian efl learners' vocabulary acquisitions. to this end, first 54 out of 64 female students, aged from 19 to 23 years, with an average of 21, were selected out of starter-level efl learners at the university of tarbiat moalem in bandar abb...

Acrylic esters, thioesters and N-acryloyl pyrrole have been identified as effective electrophiles in the enantioselective Michael addition reaction with beta-keto ester pro-nucleophiles catalysed by a cinchona alkaloid derived bifunctional organocatalyst; enantiomeric excesses of up to 98% and yields of up to 96% can be obtained for a range of Michael acceptors and pro-nucleophiles.