Patrick J. Hannan is a chemist, having received his B.S. from Catholic University (Washingon D.C.) in 1942 and his M.S. in organic chemistry from the same institution in 1948.  His research experience included three years with the Geophysical Laboratory of the Carnegie Institution, one year with the U.S. Department of Agriculture laboratory at Beltsville, MD, seven years with the Engineering Research and Development Laboratories of the U.S. Corps of Engineers at Fort Belvoir, VA, and 31 years at the U.S. Naval Research Laboratory in Washington D.C..  He retired from NRL in 1987 and, beginning in 1989, has worked as an AARP (later NOWCC) contractor with the U.S. Environmental Protection Agency on a part-time basis.
While at the Naval Research Laboratory his research concerned a feasibility study of  the use of mass cultures of algae as a source of oxygen production, and carbon dioxide removal, in nuclear submarines.  A necessary part of this work involved the development of  a gas exchange method for monitoring the growth of microorganisms on a minute-by-minute basis.  This led to the subsequent development of a bioassay for detecting trace residues of pesticides at concentrations below the detection limits of  gas chromatography/mass spectrophotometry.  These assays generally can be completed in a matter of minutes.
Since 1993, he has been a Tour Speaker for the American Chemical Society and has addressed many local sections of that organization on the topic of serendipity. In 1986 he helped to organize a symposium on serendipity as a part of the annual meeting of the American Association for the Advancement of Science. In 1988 he published four articles on serendipity in Chemtech. For more than 24 years he was a member of Toastmasters International and in 1976 was awarded first prize in the annual humorous speech contest in District 36 of that organization.
He lives in the Washington DC area and is available for speaking engagements. You can contact him at this email address: