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Curie (kürēˈ), family of French scientists. Pierre Curie, 1859–1906, scientist, and his wife, Marie Sklodowska Curie, 1867–1934, chemist and physicist, b. Warsaw, are known for their work on radioactivity and on radium. The Curies' daughter Irène (see under Joliot-Curie, family) was also a scientist.

Pierre Curie's early work dealt with crystallography and with the effects of temperature on magnetism; he discovered (1883) and, with his brother Jacques Curie, investigated piezoelectricity (a form of electric polarity) in crystals. Marie Sklodowska's interest in science was stimulated by her father, a professor of physics in Warsaw. In 1891 she went to Paris to continue her studies at the Sorbonne. In 1895 she married Pierre Curie and engaged in independent research in his laboratory at the municipal school of physics and chemistry where Pierre was director of laboratories (from 1882) and professor (from 1895).

Following A. H. Becquerel's discovery of radioactivity, Mme Curie began to investigate uranium, a radioactive element found in pitchblende. In 1898 she reported a probable new element in pitchblende, and Pierre Curie joined in her research. They discovered (1898) both polonium and radium, laboriously isolated one gram of radium salts from about eight tons of pitchblende, and determined the atomic weights and properties of radium and polonium. The Curies refused to patent their processes or otherwise to profit from the commercial exploitation of radium. For their work on radioactivity they shared with Becquerel the 1903 Nobel Prize in Physics.

The Sorbonne created (1904) a special chair of physics for Pierre Curie; Marie Curie was appointed his successor after his death in a street accident. She also retained her professorship (assumed in 1900) at the normal school at Sèvres and continued her research. In 1910 she isolated (with André Debierne) metallic radium. As the recipient of the 1911 Nobel Prize in Chemistry she was the first person to be awarded a second Nobel Prize. She was made director of the laboratory of radioactivity at the Curie Institute of Radium, established jointly by the Univ. of Paris and the Pasteur Institute, for research on radioactivity and for radium therapy.

During World War I, Mme Curie devoted her energies to providing radiological services for hospitals. In 1921 a gram of radium, a gift from American women, was presented to her by President Harding; this she accepted in behalf of the Curie Institute. A second gram, presented in 1929, was given by Mme Curie to the newly founded Curie Institute in Warsaw. Five years later she died from the effects of radioactivity. In 1995 Marie and Pierre Curie's ashes were enshrined in the Panthéon, Paris; she was the first woman to be honored so in her own right.


Among the numerous and valuable writings of the Curies are Marie Curie's doctoral dissertation, Radioactive Substances (2 vol., 1902; tr. 1961); Traité de radioactivité (1910); Radioactivité (1935); and her biography of Pierre Curie (1923, tr. 1923). Pierre Curie's collected works appeared in 1908. A biography of Marie Curie was written by her daughter Ève Curie (tr. 1937). See also biographies by R. W. Reid (1974), F. Giroud (tr. 1986), S. Quinn (1995), and B. Goldsmith (2004); S. Emling, Marie Curie and Her Daughters (2012).

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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



a subsidiary unit of the activity of a nuclide in a radioactive source (activity of an isotope). The unit was named in honor of the French scientists P. Curie and M. Sklodowska Curie. It is abbreviated Ci in international usage. The curie unit was originally defined (1910) as the quantity of radon (radium emanation) in radioactive equilibrium with 1 g of radium. The quantity of radon corresponding to 1 curie has a mass of 6.51 × 10–6g and contains 1.78 × 1016 atoms. Measurements of the disintegration of radon with an activity of 1 Ci have yielded 3.7 × 1010 disintegrations per second. Refinement of the experimental data later led to abandonment of the relationship between the curie unit and the quantity of radon. The curie unit is the activity of any nuclide in which 3.700 × 1010 disintegrations take place per second.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


A unit of radioactivity, defined as that quantity of any radioactive nuclide which has 3.700 × 1010 disintegrations per second. Abbreviated c; Ci.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


a unit of radioactivity that is equal to 3.7 × 1010 disintegrations per second.


1. Marie . 1867--1934, French physicist and chemist, born in Poland: discovered with her husband Pierre the radioactivity of thorium, and discovered and isolated radium and polonium. She shared a Nobel prize for physics (1903) with her husband and Henri Becquerel, and was awarded a Nobel prize for chemistry (1911)
2. her husband, Pierre . 1859--1906, French physicist and chemist
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
References in periodicals archive ?
The lower-bound estimate of annual willingness to pay is about 35 cents per person per bequerel or $13 per person per picocurie reduction.
Even if your residence tests high, you need not resign yourself to radon, Baskin says: "Look for a private contractor who will guarantee his work to put your house below four picocuries per liter." The fix-up bills may run as high as $1,500, but are often far less.
The new proposal allows a set amount of waste concentrated at up to 50 picocuries per gram to be disposed of in existing oilfield special waste and large-volume industrial waste landfills in the state.
The results indicate that 25% of homes haves a radon level at or above the EPA Action Level of 4 picocuries per liter of air (pCi/l) for indoor radon exposure.
As the agency works its way through the process of evaluating its standards--which the spokes-woman says now cover only the ingestion pathway, not inhalation or dermal routes--one starting point will be its current thresholds: 30 [micro]g/L for uranium, 5 picocuries per liter (pCi/L) for combined radium-226 and -228, 15 pCi/L for gross alpha radioactivity, and 4 millirems per year for beta/gamma radioactivity.
Air that has less than 4 picocuries of radon per liter is generally thought to be acceptable, and homeowners can easily buy a test kit at a hardware store.
"The radon concentration, 1,700 picoCuries per liter, is over four hundred times the EPA-recommended level."
But regardless of what your circumstances are, problems with radon can always be safely lowered to EPA acceptable levels (below four picocuries).
If the gas builds up to a level of 4 picoCuries per liter (pCi/L) or higher, you run a long term risk of getting lung cancer.
RADIOACTIVITY IN WATER SUPPLIES is common enough in the United States that the Environmental Protection Agency has a rule about it: no more than 5 picocuries in a liter of drinking water.
If the test returns levels above 4 pCi/L (picocuries per liter) you should negotiate for remediation of the problem.
States can choose to develop enhanced state programs addressing radon in indoor air in conjunction with individual water systems meeting a drinking water standard of 4,000 picoCuries per liter of water.