Perey

Francium was first identified in 1939 by the elegant radiochemical work of Marguerite Perey who named the element in honour of her native country. It occurs in minute traces in nature as a result of the rare (1.38%) branching decay of Ac in the series ... 

Perey, M. (1939). Sur un element 87, derive de l actinium. Comptes Rendus hebdomadaires des Seances de VAcademie des Sciences 208 97-99. 

Francium (Fr, [Rn] . 1), name and symbol, after France, the country where it was prepared (Curie Institute in Paris). Discovered (1939) by Marguerite Perey. Very rare in nature, artificially prepared, highly radioactive. 

Voirol P, Jonzier-Perey M, Porchet F, Reymond MJ, Janzer RC, et al. 2000. Cytochrome P-450 activities in human and rat brain microsomes. Brain Res 855 235-243. 

ORIGIN OF NAME In 1939 Marguerite Perey (1909-1975), a French physicist who worked for the Curie institute in Paris, named the newly discovered element after her country—France. 

Marguerite Catherine Perey, an assistant to Marie Curie, is credited with the discovery of francium-223 in 1939. Perey discovered the sequence of radioactive decay of radium to actinium and then to several other unknown radioisotopes, one of which she identified as francium-223. Since half of her sample disappeared every 21 minutes, she did not have enough to continue her work, but a new element was discovered. 

Francium Fr 1939 (Paris, France) Marguerite Perey (French) 62... 

French chemist Marguerite Perey Heavy, unstable, alkali metal produced by radioactive decay of uranium and thorium probably less than one ounce is present in the Earth s crust. 

French physicist Marguerite Perey in 1939 and named after France, weighahle amount ever has been prepared. 

The actual discovery was made by Mile. Marguerite Perey at the Curie Institute in Paris. In 1939 she purified an actinium preparation by removing all the known decay products of this element. In her preparation she observed a rapid rise in beta activity which could not be due to any known substance. She was able to show that, while most of the actinium formed radioactinium, an isotope of thorium, by beta emission, 1.2 0.1 per cent of the disintegration of actinium occurred by alpha emission and gave rise to a new element, which she provisionally called actinium K, symbol AcK (35, 36). This decayed rapidly by beta emission to produce AcX, an isotope of radium, which was also formed by alpha emission from radioactinium. Thus AcK, with its short half-life, had been missed previously because its disintegration gave the same product as that from the more plentiful radioactinium. 

The properties of this new element left no doubt that it was the missing alkali, eka-cesium, number 87. In 1946 Mile. Perey suggested that the name actinium K be kept for the naturally occurring isotope which resulted from the decay of actinium, but that element 87 in general... 

Mile. Perey has recently shown that when francium is injected into rats, it is found in greatest concentration in the excretory organs, the kidneys, saliva, and liver (42). In rats suffering from sarcoma, the francium activity was higher in the tumor tissue than in normal muscular tissue (43). Thus the element may eventually have medicinal uses. 

Perey, M., Proprietes physiques de I element 87 actinium K et son emploi... 

Mile. Marguerite Perey detects element 87 (francium) which is formed by the alpha-disintegration of a small percentage of the atoms of actinium. 

The only additional element about which there had been considerable uncertainty until comparatively recent times is element 87, francium (Fr), which is the last of the alkali metals in Group I. This element was finally identified by Perey in 1937 as a product of the decay of the naturally occurring actinium isotope of mass 227 ... 

Eap CB, Bender S, Sirot EJ, Cucchia G, Jonzier-Perey M, Baumann P, Allorge D, Broly F. Nonresponse to clozapine and ultrarapid CYP1A2 activity clinical data and analysis of CYP1A2 gene. J Clin Psychopharmacol 2004 24 214—219. 

The element francium is named for the country of France and its most stable isotope is known as actinium K. Dimitri Mendeleev assigned it the name eka-cesium prior to its actual discovery, although at this time it was also known as russium, virginium, and moldavium. Marguerite Perey, a one-time assistant of Marie Curie, discovered francium in 1939. It is not found in its elemental state and less than one ounce is thought to exist in Earth s crust at any one time. 

A tiny amount of a very unstable species (half-life, 21 minutes) has been detected among the decay products of actinium tracer experiments by Mile. M. Perey showed that this species has the same chemistry as that of cesium and is presumably the heaviest alkali metal. It is named francium after Mile. Perey s homeland. 

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