Joliot-Curie

F. Joliot and Irene Joliot-Curie (Paris) synthesis of new radioactive elements. 

In 1921, Irene Curie (1897-1956) began research at the Radium Institute. Five years later she married Frederic Joliot (1900-1958). a brilliant young physicist who was also an assistant at the Institute. In 1931, they began a research program in nuclear chemistry that led to several important discoveries and at least one near miss. The Joliot-Curies were the first to demonstrate induced radioactivity. They also discovered the positron, a particle that scientists had been seeking for many years. They narrowly missed finding another, more fundamental particle, the neutron. That honor went to James Chadwick in England. In 1935,... 

Jeffryes, Alec, 628 Joliot, Frederic, 517 Joliot-Curie, Irfcne, 248 Joule The base SI unit of energy, equal to the kinetic energy of a two-kilogram mass moving at a speed of one meter per second, 135,635 Joule, James, 199... 

Laboratoire Joliot-Curie, Ecole Normale Superieure de Lyon, 46 Allee d ltalie, 69007 Lyon, France Laboratoire de Biologic Moleculaire de la Cellule, CNRS-UMR 5161/INRA 1237/IFR128 Biosciences Lyon-Gerland Ecole Normale Superieure de Lyon, 46 Allee d ltalie, 69007 Lyon, France Institut Albert Bonniot, INSERM U309, 38706 La Tranche cedex, France... 

Laboratoire Joliot-Curie et Laboratoire de Physique, CNRS, Ecole Normale Superieure de Lyon, 69364 Lyon Cedex 07, France... 

Then, in 1932, Irene Joliot-Curie (the daughter of Marie Curie) and her husband, Jean Joliot, published a paper reporting that gamma rays were produced when paraffin was bombarded with alpha particles. When Rutherford and Chadwick read the paper, they didn t believe it. They suspected that what the two French physicists had seen was not gamma rays but neutrons. 

Mme. Curie and her daughter, Mme. Joliot-Curie. The latter published many papers on the radioactive elements. During World War I, while still very young, she assisted her mother in the radiological service to the wounded. With her husband, Dr. F. Joliot of the Institut de Radium in Paris, she prepared artificial radioactive elements. 

The creation, by neutron bombardment of uranium, of the so-called transuraniums is based on the discovery of artificial radioactivity by M. and Mme. Joliot-Curie. Irene Curie was bom in Paris in September, 1897, the elder daughter of M. and Mme. Pierre Curie of honored memory. Both in Poland and in France she had many relatives who were devoting their lives to science, and from her earliest childhood she lived in a scientific atmosphere, among distinguished chemists and physicists. When Irene was less than a year old, her mother discovered the radioactive element polonium, which was destined to play an important part in the later researches of both mother and daughter. A few months later M. and Mme. Curie discovered another element of even greater importance, which they named radium. 

Since the Joliot-Curies believed that a similar capture of the alpha-particle, with formation of an isotope of phosphorus, had occurred during the bombardment of the aluminum, they treated a piece of irradiated aluminum with hydrochloric acid. The liberated hydrogen carried with it the new activity, probably in the form of phosphine, leaving the aluminum residue inactive. The nuclear reaction which took place during the bombardment was therefore as follows ... 

M. and Mme. Joliot-Curie showed that the magnesium atom, when similarly bombarded, also captures a helion and emits a neutron, as follows ... 

Since other projectiles, such as neutrons, protons, and deuterons, have also been used to produce artificial radioactivity, the number of active elements thus created already exceeds by far the number of naturally occurring radio-elements (129, 130, 131). By January, 1940, three hundred and thirty artificial radioactivities had been described these include isotopes of every known element in the range of atomic numbers 1 to 85 inclusive, as well as isotopes of thorium (atomic number 90) and of uranium (atomic number 92) (132). Thus the work of M. and Mme. Joliot-Curie opened up vast avenues of research on the physical, chemical, and radioactive properties of these isotopes and on their therapeutic uses. In 1935 they were awarded the Nobel Prize in chemistry (133). 

M. and Mme. Joliot-Curie made further studies on the gamma-radiation of ionium, on chain reactions, and on neutrons and artificial radioactivity. The elements discovered with the aid of this new science will be discussed in Part 31. Mme. Joliot Curie died in Paris on March 17,1956 (136) after distinguished service to France. Frederic Joliot-Curie died in Paris on August 14,1958. 

Boyer, Les Prix Nobel de 1935. Une visite M. et Mme. Joliot-Curie,... 

Bothe s radiation in fact consisted of neutrons, as Chadwick realized and proved in a series of experiments frantically conducted before the truth dawned on the Joliot-Curies (or someone elsej.t... 

In 1934 the Hungarian physicist Leo Szilard filed a patent with the British Patent Office. It was based on an idea, nothing more - an idea about how to harness nuclear energy. The Joliot-Curies had shown that bombarding nuclei with particles can induce radioactive decay artificially. And the work of Bothe and Chadwick had demonstrated that some radioactive nuclei emit neutrons. So what would happen if neutrons induced nuclear decay that led to more neutrons The result might be a chain reaction a self-sustaining release of nuclear energy. 

Joliot-Curie, I., Oeuvres dc Mario Sklodowska Curie, pp. 143-239. Acad. Polonaise des Sciences, Warsaw, 1954. 

JOLIOT-CURIE. IRENE 11897-195ft. A French nuclear scientist who won the Nohel prize for chemistry with her husband Frederick Joliet-Curie. Their joint work involved production of artiliciul radioactive elements by using t/-rays to bombard boron. They discovered that hydrogen-containing material when exposed to what they considered p rays would emit protons. Tliev were involved in many firsts they gave Ihe first chemical proof of aitillcial transmutation and of capture of alpha particles, and were the firsi to prepare positron emitter. Her career started with a Sc.D. at the Univ ersity of Paris, and included scores of honors and awards. 

Before the end of 1933 Fermi developed his theory of 0 decay,52 in January 1934 Joliot-Curie discovered the radioactivity induced by a particles,53 and Fermi that induced by neutrons.54 Neutron physics was at the beginning of a new unexpected fast development. 

Wydzial Chemii, Uniwersytet Wroclawski, ul. F. Joliot-Curie 14, 50-383 Wroclaw, Poland e-mail llg wchuwr.pl... 

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