Nobel Prize-winning Egyptian chemist Zewail dies - state TV

U.S.-Egyptian Nobel prize-winning scientist Ahmed Zewail attends a discussion on Egypt's new constitution at the Shura Council in Cairo in this file September 11, 2012 photo. REUTERS/Mohamed Abd El Ghany

CAIRO (Reuters) - Nobel Prize-winning Egyptian-American chemist Ahmed Zewail, a science and technology advisor to President Barack Obama and the first U.S. science envoy to the Middle East, died on Tuesday in the United States, his spokesman told Egyptian state TV.

Zewail, who was 70 and a member of the California Institute of Technology (Caltech) faculty, was the sole recipient of the Nobel chemistry prize in 1999 for his pioneering work in femtochemistry, the study of chemical reactions in ultra-short time scales.