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Curie Marie
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Curie, Marie, née Maria Sklodowska (1867-1934), French physicist and twice Nobel laureate, best known for her work on radioactivity, with her husband Pierre. Maria Sklodowska was born in Warsaw, Poland, which was then part of the Russian Empire. Her father, an ardent Polish nationalist, taught mathematics and physics at a secondary school, but was denied promotion because of his political views, which he passed on to his daughter. She won a gold medal at school and then participated in the “underground” university, which aimed at maintaining Polish culture in the face of Russian domination. There she was influenced by the high esteem in which its members held science. She found employment as a governess before joining her sister in Paris in 1891. She continued her scientific studies at the Sorbonne, where she came first in physics in 1893. In 1894 she met Pierre Curie, whom she married the following year. f2t9tj
Following the discovery of X-rays by Wilhelm Roentgen and the discovery of the emission of novel radiations from uranium in 1896 by Antoine Becquerel, Marie Curie turned her attention to the question of whether there were any other elements that emitted these rays. In 1898 she discovered that such rays were emitted in unexpected strength by the uranium-containing mineral pitchblende, for which she coined the term “radioactive”. Her observations led her to conclude that there was a previously unknown chemical element in the pitchblende. Both the Curies then made a Herculean effort to reduce the pitchblende chemically, repeatedly dissolving it and crystallizing it out to concentrate the unknown component. In the end they obtained a few hundredths of a gram containing the source of the radiation. From the spectrum of this material they confirmed the existence of a new element, which they named polonium after Marie Curie’s homeland. In further confirmatory experiments they found a second highly radioactive element, which they named radium. It was not until 1902 that they isolated chemically a sample of radium.



In 1903 the Curies were jointly awarded, with Becquerel, the Nobel Prize for Physics. In 1906 Pierre Curie was killed in a road accident. Thereafter Marie Curie took over Pierre’s chair, becoming the first woman to teach at the Sorbonne. She continued her theoretical work on radioactivity, introducing into physics the terms “disintegration” (the breakdown of an atom in radioactivity) and “transmutation” (the radioactive alteration of an atom into an atom of a different element). In 1911 she won the Nobel Prize for Chemistry.
During World War I Curie played an active role in the use of radiation for medical purposes, an interest that became dominant thereafter. She became perhaps the most famous woman in the world, a reputation about which she had mixed feelings, since it interfered with her scientific work, which for her always came first. However, she was able to use her fame to promote the medical uses of radium, by facilitating the foundation of radium therapy institutes in France, Poland, the United States, and elsewhere (see Radiotherapy). She was thus able to give concrete expression to her belief in the value of science to humanity, a belief that she had held since her days in the Polish underground university.
Throughout the 1920s Marie Curie’s health declined and she had to have several cataract operations. Because of lack of knowledge about the dangers of radioactivity, she had been exposed during her career to massive doses of radiation (see Radiation Effects, Biological). In 1934, as a consequence of this, she died of aplastic anaemia in an Alpine sanatorium.



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