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[en] This publication describes our work in applying paper chromatography to the fields of mineralogy and geology. We have studied the separation and determination of the following elements: Nb, Ta, Ti, Co, Cu, Mn, Sn, Ge, As, Sb, Bi, U, Th, Be, Au, Pb, Zn, V and Mo. The development of separation methods for these various elements has led us to solve many interference problems. These methods make it possible to separate and measure mineral components. They also enable us to search for trace elements in ores, rocks soils and carbonaceous materials. Finally let us point out that this technique may equally be used for analysis in very radioactive environment. (author)
[fr]Dans cette etude, nous etendons le champ d'application de la chromatographie sur papier aux domaines de la mineralogie et de la geologie. Nous avons etudie la separation et la determination des elements suivants: Nb, Ta, Ti, Co, Cu, Mn, Sn, Ge, As, Sb, Bi, U, Th, Be, Au, Pb, Zn, V et Mo. La mise au point des methodes de separation concernant ces differents elements nous a amenes a resoudre de nombreux problemes d'interference. Ces methodes permettent la separation et le dosage des constituants des mineraux, ainsi que la recherche d'elements en traces dans les minerais, les roches, les sols et les materiaux carbonnes. Signalons pour terminer que cette technique peut egalement trouver son utilisation dans le domaine de l'analyse en milieu tres radio-actif. (auteur)
[en] The possibility that emerged after the last World War that useful power could be produced from nuclear fission led to optimistic estimates that nuclear power would prove to be the solution to the world's energy problems. The possible advantages of nuclear methods of power production compared with conventional means are discussed at the World Power Conference. The 1962 Conference with its theme 'The Changing Pattern of Power' will undoubtedly attract great interest in a world where the change-over from conventional to nuclear fuels for power production has started in some countries and is being actively examined in others. It is generally being realized that even though a country may possess indigenous supplies of uranium or thorium minerals, the building up of a nuclear industry i s a long and expensive process and the alternative of depending on countries more advanced in nuclear technology for the supply of materials, skill and know-how is costly in foreign exchange and international prestige. Many of the industrialized countries, still possessing supplies of conventional fuels, are preparing for the day when their reserves will become depleted and are embarking on training schemes to ensure a continuing supply of engineers and scientists skilled in nuclear arts
[en] Safety in mining radioactive ores, and in milling and treating them, has been a serious preoccupation for some thirty years. Much earlier than this, however, a high incidence of lung cancer had been reported among the miners of the Erzgebirge mountains in the German-Czechoslovak border region (places familiar under the names of Schneeberg and St. Joachims thai). Investigations into deaths from radium poisoning began at these mines in 1937, and the results seemed to indicate a causal connection between the radioactive substances and the development of lung cancer and other diseases. These matters were discussed in Vienna at the symposium on Radiological Health and Safety in Nuclear Materials Mining and Milling, 26-31 August 1963. The symposium was organized by IAEA and co-sponsored by ILO and WHO; some 70 papers were presented. The purpose of the meeting was to collect and compare the very widely scattered research results and practical experience in this field. One conclusion which emerged was that the milling of uranium ore involves no unusual problem. Provided standard controls - as applied to the treatment of other minerals - are strictly enforced, exposure to radiation can be kept to a minimum. In the actual mining of uranium, the problems are only beginning to be clearly defined, but it seems to be well established that exposure of miners to excessive levels of radon will have most serious consequences. In a complicated pattern there are many factors at work, ranging from the physical behaviour of sundry radioactive substances to the personal histories of individual miners. The need for considerably more research was stressed throughout the discussions.
[en] A mineralogical analysis is made to ascertain the effects of acid bleaching on normalized conditions. Uranium is mainly found under uranotile, pitchblende and autunite form with an average assay of 0.4 p. ct. The loss of uranium in tailings under current conditions of attach, mainly is due to pitchblende resistance, being practically no leachable, and to uranium absorption by hydrated iron oxides and colloidal ores. This last problem will be discussed in a next paper. (Author) 5 refs
[en] Whereas fixation of uranium by sediments occurs with such an importance that these sediments may be actual uranium sources, and as it notably the case for carboniferous shales, the author aimed at understanding mechanisms which govern the enrichment of black shales in uranium in the case of the Saint-Hippolyte site. The author first presents the main properties of uranium in solution which may help the understanding of its geochemistry. He proposes a summarised presentation of works which addressed uranium-containing black shales in order to have an overview of present knowledge. Then, based on relationships between uranium and some constituents of these shales, he tries to highlight valid hypotheses of formation. Article published in 'Bulletin du Service de la carte geologique d'Alsace et de Lorraine', tome 14, no. 4, 1961. Sedimentologie et pedologie, geochimie de la surface 1961. pp. 179-208.
[fr]L'uranium est extremement disperse dans l'ecorce terrestre; sa teneur moyenne est voisine de 4 10-4 pc en uranium metal. On le trouve concentre en gisements filoniens et dans certaines roches sedimentaires. La fixation de l'uranium par les sediments se fait avec une telle ampleur que ceux-ci peuvent constituer de veritables gites uraniferes. Divers schistes noirs en sont des exemples; ils sont soit d'origine marine, tels ceux du Chattanooga (Etats-Unis d'Amerique), soit d'origine lacustre tels ceux de Saint-Hippolyte (Haut-Rhin). Les schistes noirs uraniferes de Saint-Hippolyte sont d'age westphalien; ils affleurent en quatre lambeaux; pres de Thannenkirch (1), au Schaentzel (2), au Teufelsloch (3) et au Kloegelberg (4). L'uranium est dissemine de facon irreguliere a travers toute la masse et aucun mineral n'a pu etre identifie (A. Grimbert, A. Carlier, 1957). Les problemes que pose la migration de l'uranium a la surface de l'ecorce terrestre: mise en solution, transport, depot avec concentration eventuelle, ne sont pas encore resolus a l'heure actuelle. Nous nous sommes efforces de comprendre les mecanismes qui ont preside a l'enrichissement en uranium des schistes noirs de Saint-Hippolyte. Ce travail a pu etre effectue grace a l'aide materielle du Commissariat a l'Energie Atomique. Article publie dans le 'Bulletin du Service de la carte geologique d'Alsace et de Lorraine', tome 14, no. 4, 1961. Sedimentologie et pedologie, geochimie de la surface 1961. pp. 179-208.