Robert Emerson (chemist)

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Robert Emerson (* 4. November 1903 in New York City ; † 4. February 1959 ) was an American chemist and biophysicist , noted for research on photosynthesis .

Life

From 1920 Emerson studied animal and plant physiology at Harvard University with a master's degree in zoology from WJV Osterhout in 1925. As a post-doctoral student , he was with Richard Willstätter in Munich and Otto Heinrich Warburg in Berlin. In 1926 he received his doctorate in botany near Warburg in Berlin. In 1927 he was back at Harvard and studied photosynthesis on algae. From 1930 he was professor at Caltech and from 1937 at the laboratory for plant physiology of the Carnegie Institution in Washington, DC In 1941 he was again at Caltech and from 1946 professor at the University of Illinois . He died in an airplane accident at LaGuardia Airport in 1959 when his plane (American Airlines Flight 320) crashed into the East River, killing 65. His friend and colleague Eugene Rabinowitch published post-processed papers.

In 1932 he and the student William Arnold found that around 2400 chlorophyll molecules are necessary for the production of an oxygen molecule and concluded that these form a photosynthetic unit with an enzyme (the concept was introduced by him). In the early 1940s he and Charlton M. Lewis (1905-1996) determined the quantum efficiency of the photosynthetic reaction and found deviations from the value of 4 light quanta per oxygen atom found by Otto Warburg: according to Emerson and Lewis it was 8 to 12. This led to one Controversy with Warburg. Also in 1943 he discovered the red drop effect, initially inexplicable for Emerson , the decrease in photosynthesis at greater wavelengths towards the infrared. In 1957 he discovered the Emerson effect , which in addition to the light absorbed directly by chlorophyll, also contributes light of other wavelengths to photosynthesis. Thereafter there had to be more than one photosynthetic unit.

Emerson had been a member of the National Academy of Sciences since 1953 . In the same year he was also elected to the American Academy of Arts and Sciences .

Ralph Waldo Emerson was his great-uncle. His father, Haven Emerson, was the director of the New York City Public Health Service.

literature

  • Emerson, Robert. In: Winfried R. Pötsch, Annelore Fischer, Wolfgang Müller: Lexicon of important chemists. Harri Deutsch 1989, ISBN 978-3-817-11055-1 , p. 224.
  • Eugene Rabinowitch: Biographical Memoirs National Academy. 1961 ( online , PDF; 939 kB; English).

Web links

Individual evidence

  1. ^ Members of the American Academy. Listed by election year, 1950-1999 ( [1] ). Retrieved September 23, 2015.
personal data
SURNAME Emerson, Robert
BRIEF DESCRIPTION American chemist and biophysicist
DATE OF BIRTH November 4, 1903
PLACE OF BIRTH New York City
DATE OF DEATH 4th February 1959
Place of death New York City