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Week 17

Week 17: April 23 – 29 (Archive)

April 23

  • Max K. E. L. Planck, born 1858, introduced quantum theory (1900); researched thermodynamics; Nobel Prize in Physics (1918).
  • Rohm & Haas Co. incorporated in 1917.

April 24

  • Jean C. de Marignac, born 1817; in 1880, discovered gadolinium (Gd, 64).

April 25

  • Wolfgang Pauli, born 1900, discovered exclusion principle; Noble Prize in Physics (1945).
  • James D. Watson and Frances H. C. Crick published "Molecular Structure of Nucleic Acids: A Structure of Deoxyribose Nucleic Acid," in 1953.

April 26

  • Michael Smith, born 1932, invented oligonucleotide-based, site-directed mutagenesis of DNA; Nobel Prize in Chemistry (1993).

April 27

  • Antoine-Laurent Lavoisier reported that heating red calx (metal oxide) of mercury, HgO, in presence of powdered charcoal resulted in liberation of oxygen and reduction of mercury calx in 1775.
  • Wallace Carothers, born 1896, developed nylon (1935).
  • Philip H. Abelson, born 1913; in 1940, codiscovered neptunium (Np, 93).
  • Albert Ghiorso et al. announced the discovery of element 105, produced by bombardment of californium-249 with nitrogen-15, in 1970.

April 28

  • Franz K. Achard, born 1753, first to prepare a platinum crucible (1784); invented process for extraction of sugar from sugar beets; opened first beet sugar factory (1801).
  • Barry Sharpless, born 1941, discovered and developed many catalytic oxidation proceses for stereoselective oxidation; Nobel Prize in Chemistry (2001).

April 29

  • Atlantic Richfield Co. incorporated in 1870.
  • Harold C. Urey , born 1893; in 1932, first to isolate heavy water (D2O); Nobel Prize in Chemistry (1934).
  • Nashua incorporated as Nashua Card, Gummed & Coated Paper in 1904.