Martin Knudsen

Martin Hans Christian Knudsen (February 15, 1871 - May 27, 1949) was a Danish physicist who taught and conducted research at the Technical University of Denmark

He is primarily known for his study of molecular gas flow and the development of the Knudsen cell, which is a primary component of molecular beam epitaxy systems.

Martin Hans Christian KNUDSEN, Physicist

  Born 15 Feb. 1871, Hansmark.  Died 27 May 1949, Copenhagen.
  Knudsen received the University's gold medal in 1895 and earned his master's degree in physics the following year.  He became lecturer in physics at the University in 1901 and professor in 1912, when C. Christiansen (1843-1917) retired.  He held this post until his own retirement in 1941.
  Knudsen is renowned for his work on kinetic-molecular theory and low-pressure phenomena in gases.  His name is associated with the Knudsen flow, Knudsen number, and Knudsen gases.  Also there is the Knudsen Equation, and two instruments, the Knudsen absolute manometer and Knudsen gauge. His book, The Kinetic Theory of Gases  (London, 1934), contains the main results of his research.
  Knudsen was also very active in physical oceanography, developing methods of defining properties of seawater.  He was editor of Hydrological Tables (Copenhagen-London, 1901).

References: 1. Matematiken i Danmark (Mathematics in Denmark) by Niels Nielsen, Gyldendalske Boghandel, Nordisk Forlag, København. Vol. I: 1801-1908, published 1910; Vol. II: 1528-1800, published 1912. (In Danish). Note: This important work is a compilation of Danish mathematical writings. In addition to mathematicians, the short biographical notes include many physicists, astronomers, and early natural philosophers, including medical practitioners. 2. Kemien i Danmark (Chemistry in Denmark) by Stig E. Veibel. Vol. I: Kemiens historie i Danmark (The History of Chemistry in Denmark), 1939. Vol. II: Dansk Kemisk Bibliografi, 1800-1935 (Danish Chemistry Bibliography), 1943. Vol III: Danske Kemikere (Danish Chemists), edited by Bodil Jerslev, 1968 (Three of six chapters by Stig Veibel). All published by Nyt Nordisk Forlag, Copenhagen. (In Danish). Note: Vol. II is a compilation of Danish publications in chemistry and includes works by physicists, geologists, biologists, and physicians, along with biographical information. 3. Dictionary of Scientific Biography, Charles Coulston Gillispie, editor, Scribner's & Sons, New York, 1980 (16 Volumes). Supplement of 1990 (Volumes 17 and 18).

Submitted 6-13-06 by V. Thomsen, Ed.D.