Joliot

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

The first radioactive isotopes to be made in the laboratory were prepared in 1934 by Irene Curie and her husband, Frederic Joliot They achieved this by bombarding certain stable isotopes with high-energy alpha particles. One reaction was... 

Marie and Irene Curie, and their husbands, Pierre Curie and Frederic Joliot. Marie Curie (1867-1934) was born Maria Sklodowska in Warsaw, Poland, then a part of the Russian empire. In 1891 she emigrated to Paris to study at the Sorbonne, where she met and married a French physicist, Pierre Curie (1859-1906). The Curies were associates of Henri Becquerel, the man who discovered that uranium salts are radioactive. They showed that thorium, like uranium, is radioactive and that the amount of radiation emitted is directly proportional to the amount of uranium or thorium in the sample. 

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,... 

Irene Curie and Frederic Joliot received the Nobel Prize in physics. The award came too late for Irene s mother, who had died of leukemia in 1934. Twenty-two years later. Irene Curie-Joliot died of the same disease. Both women acquired leukemia through prolonged exposure to radiation. 

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... 

Prochiantz A, Joliot A (2003) Can transcription factors function as cell-ceU signaUing molecules Nat Rev Mol Cell Biol 4 814-819... 

Curie, I. and Joliot, F. (1932). Emission de protons de grande vitesse par les substances hydrogenees sous l influence des rayons y tres penetrants. Comptes Rendus hebdomadaires des Seances de TAcademie des Sciences 194 273-275. 

Radiometric methods are unique for their ability to provide directly the surface concentration of the adsorbate. A method for in situ study of electrochemical reactions on solid electrodes was invented by Joliot. ° He used a thin gold foil as an electrode which at the same time served as the window of the radiation counter. Johot determined the kinetics and the effect of tartaric acid on polonium electrodeposition on gold. The method was later further developed and improved (e.g.. Refs. 102,103). 

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... 

Service Hospitalier Frederic Joliot, Departement de Recherche Medicate, CEA,... 

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. 

Rutherford and Chadwick knew that if the Joliots realized that their conclusions were erroneous, they might discover the neutron first. So Chadwick immediately went to work performing new experiments. He soon found that if beryllium was bombarded with alpha particles, a kind of radiation consisting of particles with a mass close to that of the proton were produced. He ruled out the possibility that the radiation consisted of gamma rays by showing that, if it did, the gamma rays would have insufficient energy to produce the effects that were observed. Chadwick had discovered Rutherford s neutron. 

Chadwick had beaten the Joliots to the discovery. Nevertheless, the story ended happily for all those involved. The Joliots continued... 

Joliot P, Joliot A (2006) Cyclic electron flow in C3 plants. Biochim Biophys Acta 1757 362-368... 

Oka, Y. Physics of supercritical-pressure light water cooled reactors. Proc. 1998 Frederic Joliot Summer School in Reactor Physics, Caderache, France, and references cited herein, 1998 240-259 pp. 

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. 

Jean-Fr6ddric Joliot, 1900-1958. Physicist and chemist at the Curie Institute. He has made many important researches on the phenomenon of recoil and the conservation of momentum, on the electrochemical behavior of the radioelements, and on the expulsion of atomic nuclei and the existence of the neutron. 

Their joint papers on The numbers of ions produced by alpha rays of radium C in air were published in the Comptes rendus in 1928. In the following year they investigated the nature of the absorbable radiation which accompanies the alpha-rays from polonium. In 1930 M. Joliot presented his thesis for the doctorate, which was entitled The electrochemistry of the radio-elements, and Mme. Joliot continued her study of polonium (123). 

M. and Mme. Joliot showed that boron and lithium, when they are bombarded with alpha-rays from polonium, also emit penetrating radiations (126). Their work gave early evidence of the probable existence of the neutron, a hypothesis which has since been fully verified by the researches of Professor James Chadwick, the 1935 Nobel laureate in physics (127). 

Since the alpha-ray impacts shattered only a minute proportion of the total number of atoms of boron, aluminum, or magnesium, the chemical identification of the products was extremely difficult. These indefatigable workers, however, accomplished even this. Although it would have been impossible to identify the products simply by ordinary chemical means, the Joliots were able to take advantage of the radioactive nature of the products formed. Since they had good reason to believe that the boron atom had captured a helion and ejected a neutron and that the new element was therefore probably an isotope of nitrogen, they heated some bombarded boron nitride with caustic soda and found that the liberated... 

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