CTReaderEast.com Local News, Read all about it!: Jacob Bigeleisen, Isotope Chemist on Manhattan Project, Dies at 91 Jacob Bigeleisen, Isotope Chemist on Manhattan Project, Dies at 91 ================================================================================ Feeder on 01 September, 2010 02:45:53 Dr. Bigeleisen’s approach was ultimately unsuccessful, but he went on to open a new field of chemistry that studied ways to speed up or slow down chemical reactions.