Confusion and a lot of questions exist as to detonation and pre-ignition. Sometimes you hear mistaken terms like pre-detonation. Detonation is one phenomenon that is abnormal combustion. Pre-ignition is another phenomenon that is abnormal combustion.
Martha R. Herbert, PhD, MD, is an assistant professor of neurology at Harvard Medical School, a pediatric neuroscientist at the Massachusetts General Hospital in Boston, and an affiliate of the Harvard-MIT-MGH Martinos Center for Biomedical Imaging.
For the early American botanist, see Martha Daniell Logan. Martha Logan is a fictional character played by Jean Smart in the television series 24. As the first lady of the United States within the 24 universe, she is the capable yet mercurial wife of President Charles Logan. Critics praised Martha Logan as the breakout character of the show's 2005-2006 season.