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Irène had joined, began to operate in earnest, and became a centre for nuclear physics and
chemistry. Marie Curie, now at the highest point of her fame and, from 1922, a member of
the Academy of Medicine, researched the chemistry of radioactive substances
and their medical applications.
In 1921, accompanied by her two daughters, Marie Curie made a triumphant journey to the United
States to raise funds for research on radium. Women there presented her with a gram of radium for
her campaign. Marie also gave lectures in Belgium, Brazil, Spain and Czechoslovakia and, in
addition, had the satisfaction of seeing the development of the Curie Foundation in Paris, and the
inauguration in 1932 in Warsaw of the Radium Institute, where her sister Bronia became director.
One of Marie Curie's outstanding achievements was to have understood the need
to accumulateintense radioactive sources, not only to treat illness but also to maintain an abundant
supply for research. The existence in Paris at the Radium Institute of a stock of 1.5 grams of radium
made a decisive contribution to the success of the experiments undertaken in the years around
1930. This work prepared the way for the discovery of the neutron by Sir James Chadwick and,
above all, for the discovery in 1934 by Irène and Frédéric Joliot-Curie of artificial radioactivity. A few
months after this discovery, Marie Curie died as a result of leukaemia caused by exposure to
radiation. She had often carried test tubes containing radioactive isotopes in her pocket, remarking
on the pretty blue-green light they gave off.
Her contribution to physics had been immense, not only in her own work, the importance of which
had been demonstrated by her two Nobel Prizes, but because of her influence on subsequent
generations of nuclear physicists and chemists.