Editing 1940 in science (section)

==Chemistry==
* February 27 – The [[radioactive]] [[isotope]] [[carbon-14]] is discovered by [[Martin Kamen]] and [[Sam Ruben]] at the [[University of California, Berkeley]].<ref>{{cite journal|last=Kamen|first=Martin D.|year=1963|title=Early History of Carbon-14: Discovery of this supremely important tracer was expected in the physical sense but not in the chemical sense|journal=[[Science (journal)|Science]]|volume=140|issue=3567|pages=584–590|doi=10.1126/science.140.3567.584|jstor=1710512|pmid=17737092|bibcode=1963Sci...140..584K }}</ref>
* May 15 – Women's [[stocking]]s made of [[nylon]] are first placed on sale across the United States.<ref>{{cite web|title=the history of nylon |url=http://www.caimateriali.org/index.php?id=32 |first=L. |last=Trossarelli |publisher=Club Alpino Italiano, Centro Studi Materiali e Tecniche |year=2010 |accessdate=2012-02-28 |archiveurl=https://web.archive.org/web/20120425044410/http://www.caimateriali.org/index.php?id=32 |archivedate=2012-04-25 |url-status=live }}</ref>
* December 14 – [[Plutonium]] is first synthesized by a team led by [[Glenn T. Seaborg]] and [[Edwin McMillan]] at the University of California, Berkeley by bombarding [[uranium-238]] with [[deuteron]]s.
* The radioactive [[Chemical element|element]] [[Astatine]] is synthesized by [[Dale R. Corson]], [[Kenneth Ross MacKenzie]] and [[Emilio Segrè]] at the University of California, Berkeley.<ref>{{cite journal|title=Artificially Radioactive Element 85|first1=D. R.|last1=Corson|first2=K. R.|last2=MacKenzie|first3=E.|last3=Segrè|journal=[[Physical Review]]|volume=58|pages=672–678|year=1940|doi=10.1103/PhysRev.58.672|issue=8|bibcode=1940PhRv...58..672C}}</ref>
* [[Neptunium]], the first [[Transuranium element|transuranic]] element, is synthesized by [[Edwin McMillan]] and [[Philip H. Abelson]] at the University of California, Berkeley.<ref>{{cite journal|doi=10.1103/PhysRev.57.1185.2|title=Radioactive Element 93|year=1940|last1=Mcmillan|first1=Edwin|journal=Physical Review|volume=57|pages=1185–6|last2=Abelson|first2=Philip Hauge|issue=12|bibcode=1940PhRv...57.1185M|doi-access=free}}</ref>
* [[Louis Plack Hammett]] coins the term ''[[Physical organic chemistry]]'' when he uses it as the title of a textbook published in New York.<ref>{{cite journal|last=Hammond|first=George S.|authorlink=George S. Hammond|title=Physical organic chemistry after 50 years: It has changed, but is it still there?|url=http://www.iupac.org/publications/pac/1997/pdf/6909x1919.pdf|journal=[[Pure and Applied Chemistry]]|publisher=[[IUPAC]]|year=1997|volume=69|issue=9|pages=1919–22|accessdate=2014-01-22|doi=10.1351/pac199769091919|s2cid=53723796}}</ref>
* [[Robert McCance]] and [[Elsie Widdowson]] published the standard text ''The Chemical Composition of Foods''.<ref>{{cite ODNB|first=Roger|last=Whitehead|title=Widdowson, Elsie May (1906–2000)|year=2004|url=http://www.oxforddnb.com/view/article/74313|accessdate=2011-08-10|doi=10.1093/ref:odnb/74313}}</ref>