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[en] The authors first review the characteristics of uraninite-pitchblende, as deduced of present literature. They set apart from typical pitchblende a black oxide aspect, which probably corresponds to neo-formations, and a 'para-pitchblende' aspect, which they relate to deep sur-oxidation of normal pitchblende. They insist on the easy replacement of pitchblende by silica. and give indications as to changes in vein stones (fluorite, quartz, etc...). A detailed study of paragenesis and successions in french uranium districts follows (including discussion of uranium of uranium-bearing coals). The authors attempt to classify french pitchblende veins. They are chiefly epithermal and poor in satellite ores. Three types of deposits are identified: massive - pitchblende type, silica type, fluorite type. These deposits, as those of Portugal, are included in granite, Central-European peri-batholitic types where uranium associates which Ni, Co, Bi and Ag, are in France both rare and poor. Finally, the authors attempt to bring out in the european Hercynian area a particular distribution of paragenetic types. (authors)
[fr]Les auteurs recapitulent d'abord les caracteres et les occurences de l'uraninite - pechblende, tels qu'ils peuvent etre degages de l'actuelle bibliographie. Ils exposent ensuite les faits qui du point de vue mineralogique seulement ressortent de l'etude mineralogique et chalcographique des pechblendes francaises et de leurs satellites. Ils distinguent de la pechblende-type un facies oxyde noir; correspondant probablement a une neoformation, et un facies parapechblende, qui est rapporte a une sur oxydation hypogene de la pechblende proprement dite. Ils insistent sur le facile remaniement de la pechblende par la slice; et donnent quelques precisions sur les modifications des gangues (fluorine, quartz, etc...). Suit l'etude detaillee des parageneses et des successions dans les districts uraniferes francais: Divisions du Limousin, de Grury, de Lachaux et de Vendee, indices du Sud Massif Central et indices des Vosges (a propos desquels est abordee la question des ''materiaux carbones uraniferes''). La conclusion constitue une tentative de classification des filons uraniferes francais. Ceux-ci, de type epithermal dominant, sont pauvres en minerais satellites. Trois types de formations sont distinguees: type a pechblende massive (dominant en Limousin), type siliceux (dominant a Lachaux), type fluore (dominant a Grury). Tous ces gites comme au Portugal, recoupent les granites, et sont tres differents des formations uraniferes a Ni, Co, Bi, Ag, U d'Europe Centrale. Les auteurs enfin exposent que quelques idees relatives a la formation de la pechblende, et tentent de faire ressortir pour l'ensemble de l'aire hercynienne europeenne une repartition particuliere des types paragenetiques. (auteurs)
[en] In this work, the authors study the french new uranium minerals: parsonsite and renardite, hydrated phosphates of lead and uranium; kasolite: silicate hydrated of uranium and lead uranopilite: sulphate of uranium hydrated; bayleyite: carbonate of uranium and of hydrated magnesium; β uranolite: silicate of uranium and of calcium hydrated. For all these minerals, the authors give the crystallographic, optic characters, and the quantitative chemical analyses. On the other hand, the following species, very rare in the french lodgings, didn't permit to do quantitative analyses. These are: the lanthinite: hydrated uranate oxide; the α uranotile: silicate of uranium and of calcium hydrated; the bassetite: uranium phosphate and of hydrated iron; the hosphuranylite: hydrated uranium phosphate; the becquerelite: hydrated uranium oxide; the curite: oxide of uranium and lead hydrated. Finally, the authors present at the end of this survey a primary mineral: the brannerite, complex of uranium titanate. (author)
[fr]Dans ce travail, les auteurs etudient les nouveaux mineraux uraniferes francais: parsonsite et renardite, phosphates hydrates de plomb et d'uranium; kasolite: silicate hydrate d'uranium et de plomb uranopilite: sulfate d'uranium hydrate; bayleyite: carbonate d'uranium et de magnesium hydrate; β uranolite: silicate d'uranium et de calcium hydrate. Pour tous ces mineraux, les auteurs donnent les caracteres cristallographiques, optiques, et les analyses chimiques quantitatives. Par contre, les especes suivantes, tres rares dans les gites francais, n'ont pas permis d'effectuer d'analyses quantitatives. Ce sont: l'ianthinite: oxyde uraneux hydrate; l'α uranotile: silicate d'uranium et de calcium hydrate; le bassetite: phosphate d'uranium et de fer hydrate; la hosphuranylite: phosphate duranium hydrate; la becquerelite: oxyde d'uranium hydrate; la curite: oxyde d'uranium et de plomb hydrate. Enfin, les auteurs presentent a la fin de cette etude un mineral primaire: la brannerite, titanate d'uranium complexe. (auteur)
[en] The present report gives an overview of the present facilities of energy productions in France and their perspectives. the electric production comes for half about power stations hydraulics and for half of thermal power stations. However due to the increase of the energy consumption, France is particularly interested by the atomic energy that appears to bring a supply in due time to the hydraulics and to limit a development of the thermal power stations to which the natural resources of France in classic fuel would not permit to cope presumably. The integration of the nuclear plants to the other production facilities will make itself gradually according to the evolution of the energy needs. (M.B.)
[fr]Le present rapport donne un apercu des moyens actuels de productions energetiques en France et de ses perspectives. la production electrique provient pour moitie environ de centrales hydraulique et pour moitie de centrales thermiques. Cependant face a l'augmentation de la consommation energetique, la France est tres particulierement interessee par l'energie atomique qui parait devoir apporter en temps utile la releve a l'hydraulique et limiter un developpement des centrales thermiques auxquels les ressources naturelles de la France en combustible classique ne permettraient vraisemblablement pas de faire face. L'integration des centrales nucleaires aux autres moyens de production se fera graduellment en fonction de l'evolution des besoins energetiques. (M.B.)
[en] The development of the research about stable and radioactive isotopes uses in biology and medicine started in France in the early years after the second World War. Close collaboration with United States led to the training of an hundred of French medical researchers in US research laboratories, twenty of whom were specifically trained about tracers uses and techniques. Since 1950, the C.N.R.S. and C.E.A. have collaborated to train French researchers to the isotopes methods, interpretation difficulties and precaution measures about radioisotopes manipulations. In the early fifties, the CEA started the radioisotopes production for medical and biology research and applications uses. The clinical uses of isotopes are presented in two main applications: diagnosis uses such as 131I for diagnosis or functional studies of thyroid gland and therapeutic treatments such as 32P for leukaemia and other cancer treatments. In a second part, the main studies subjects of basic and applied research are described: physiological and biological studies of the absorption, diffusion and distribution of different molecules as well as membrane permeability in biological systems for medicine and agronomy applications, studies of the incorporation of labelled compounds in biological and organic systems by exchange or synthesis (32P is used for renewal studies of the osseous tissue), studies of the mechanism of biochemical reactions (14C, 15N and 35S are the most used radionuclides) and endocrinology research, in particular, biochemical studies of the thyroid hormones. All these researches and applications encountered financial and delay in radioisotope production for which the CEA provided most of the labelled compounds at reasonable prices. The large development of isotopes applications in diagnosis, therapeutic as well as basic and applied research, leads to increase radionuclides demand and production delays. It discussed the different solutions to facilitate the diffusion and the use of radioisotopes for smaller laboratories structures by intensifying specific training to researchers and increasing the material and human resources. A European collaboration is also considered to facilitate the link between the medicine and biology researchers and the organist chemists who synthesize labelled compounds. (M.P.)
[en] The discover of radium element by Pierre and Marie Curie in 1898 activated the uranium ores prospecting in France and its overseas territories. Before 1945, rare and poor deposits were found with only one being operated in Madagascar and the production of nobiantalates from washing of pegmatitic eluvium. Since the setting up of the Research and Mines Department in the C.E.A. and the training of specialized exploration teams as well as the use of Geiger counters, the uranium ores prospecting has been largely developed in France. The mineralogical data resulting from studies during the pre-war period led to the discover of four main uranium ores content areas: La Crouzille deposit in Limousin characterized by large presence of pitchblende, the Bauzot deposit with massive presence of pitchblende as well, discover of mineralization traces in the Bois Noirs area where a rich uranium ore lodes were discovered afterwards and finally the madagascar deposit. Few other areas have been prospected and have got good evidences of uranium ores presence. The majority of French uranium deposits have got an 'hydrothermal' vein type with localized pitchblende or a secondary mineralization type. It described the different deposits by region and in chronological order of discover. The structural aspect and petrographic studies are discussed. The metallogenic study shows the presence of large mineralization in the French Hercynian massif. After ten years of uranium ores prospecting and mines work, it shows that France possesses numerous uranium deposits which can be qualified as large deposits and the minerals ores prospecting revealed that many deposits sites would be payable in the near future. (M.P.)
[en] This article first proposes a presentation of the tidal theory and outlines the roles of Newton (to know the phenomenon), Laplace (to understand it) and Poincare (to act on it). The author then describes some tidal characteristics, notice than they can be different in different locations of the planet in frequency (two tides a day here, one tide a day there, or negligible) as well as in amplitude. Then, he addresses the history of cycles of use of tides, notably by exploiting the filling and emptying of basins by means of turbines (simple effect dam, double effect dam, pumping). He evokes some historical projects of tidal power plants in France, and then more particularly the Rance tidal power plant project, the Chausey and Minquiers projects. Article published in 'L'Astronomie' journal, Vol. 69, Dec. 1955, p.449-469.
[en] The progress in the uses of radioisotopes has been conditioned by increasing the number of trained workers and researchers and developing theoretical teaching in universities since 1950 in France as well as developing a national control of the distribution and uses of radioisotopes. With the large diffusion and development of radioisotopes uses and applications, new rules and regulations came to control the importation, exportation, transport and utilization of radioisotopes. In the first part, it described the different French laws since 1934 and their successive modifications which ruled on the production, manipulation and utilization of radioisotopes. An inter-ministerial committee was created in 1952 to advise and inform of all the questions related to the preparation, importation, exportation, possession and distribution of radioisotopes. The transport regulations are in constant evolution and has got to meet with international recommendations. It distinguished three different type of transport: road, river and railway transport, postal transport and finally air transport. All the different transports have their specific packaging, maximum transportable quantity, maximum material intensity and labelling requirements. The regulations about customs duties are specified as well as the administrative formalities for non natural radioisotopes importation. Since 1950, diseases caused by irradiation to natural or artificial radioactive materials are recognised as professional diseases and a table of the actual regulations is presented. (M.P.)
[en] In this article, L. Kowarski, at the time (1952) in charge of the Department of Reactors and Accelerators at the Atomic Energy Commission (CEA), reviews the scientific and industrial advances made in the field of production and use of atomic energy (experimental reactors, interest of heavy water reactors, plutonium production, choice of a moderator and a cooling fluid, power generation) and examines the different directions in which the program of atomic works should be pursued in France. L. Kowarski published in 'La Technique Moderne' journal previous articles such as: 'The very high voltages and their application to elements transmutation' (February 15, 1939), and 'Atomic Energy. Present state and application prospects' (February 15, 1947). Reprint of a paper published in 'La Technique Moderne', t. XLIV, no. 5, May 1952.
[fr]Dans le tres bel article ci-dessous, M. Kowarski, actuellement charge au Commissariat a l'Energie Atomique du 'Departement des Piles et Accelerateurs', fait le point des progres scientifiques et industriels realises dans le domaine de la production et de l'utilisation de l'energie atomique, et examine les differentes directions dans lesquelles pourrait etre oriente le programme des travaux atomiques a poursuivre en France. Il n'est pas necessaire de presenter M. Kowarski aux lecteurs de La Technique Moderne. Ils ne manqueront pas de se reporter a ses precedents articles parus dans notre revue, et en particulier a ceux du 15 fevrier 1939: Les tres hautes tensions et leur application a la transmutation des elements, et du 15 fevrier 1947: L'energie atomique. Etat present et perspectives d'application. Reproduction d'un article publie dans 'La Technique Moderne', t. XLIV, no. 5, mai 1952.
[en] The authors describe a uranium point located in the old Sagmuehlen cobalt mine near Sulzburg in the Black Forest. Mineralization seems to be related to the granitic massif in the south of the Black Forest. It is in the form of thin veinlets of concreted pitchblende accompanied by loellingite and sulphides of Pb, Cu, Zn, Fe and Sb in a quarto-carbonate gangue. By enumeration of a certain number of mineralizations, the authors try to point out a gradual transition from the uranium types of the French 'Massif Central' (with sulphides BGPC, chalcedony and fluorine) to the types of Central Europe (related to Ni, Co, Bi, U and Ag ores). Although both types are located in the Hercynian mineralized provinces, the 'French Massif Central' type deposits, intra-granitic and predominantly epithermal, seem to be later than the deposits of Central Europe, located on the periphery of the granitic batholiths, and of the meso-thermal-dominant type. Reprint of a paper published in 'Bulletin de la Societe Geologique de France', t. 3, 1953, p. 441-450.
[fr]Les auteurs decrivent un point uranifere situe dans l'ancienne mine de cobalt de Sägmühlen pres de Sulzburg, dans la Foret Noire. La mineralisation semble liee au massif granitique du S de la Foret Noire. Elle se presente sous forme de minces veinules de pechblende concretionnee accompagnee de loellingite et de sulfures de Pb, Cu, Zn, Fe et Sb, dans une gangue quartzo-carbonatee. Par l'enumeration d'un certain nombre de mineralisations, les auteurs tachent de faire ressortir un passage progressif des types uraniferes du Massif Central (avec sulfures B. G. P. C., calcedoine et fluorine) aux types d'Europe centrale (lies aux minerais de Ni, Co, Bi, U et Ag). Bien que les deux types soient localises dans les provinces mineralisees hercyniennes, les gites type 'Massif Central francais', intragranitiques et a dominante epithermale, semblent plus tardifs que les gites d'Europe centrale, localises a la peripherie des batholithes granitiques, et a type mesothermal dominant. Reproduction d'un article publie dans le 'Bulletin de la Societe Geologique de France', t. 3, 1953, p. 441-450.
Nuclear energy and its industrial applications. 1 - Atomic piles and radio-isotopes: The French atomic programme; The future of atomic energy; The Nuclear Study Centre of Saclay; Fundamental notions related to nuclear reactors; Neutron spectrometer used in the Saclay pile; Determination of the transport mean free path of thermal neutrons by measuring a complex length of diffusion; Electronic equipment used in the measurement of the diffusion length in graphite; The non destructive materials test using the oscillation method in the Chatillon pile; An analogue harmonic analyser; Recent progress in reactor control; Analogue calculators pile simulators; The preparation of artificial radio-elements; Problems faced in the prospecting of radioactive ores and used equipment; Radioactive aerosols and gases in the atomic industry; A fixed health monitoring installation at the Laboratoire de Haute Activite of Saclay
[en] This publication gathers several articles which address various aspects of atomic piles and radio-isotopes. More particularly, the addressed topics are: the future of atomic energy; a presentation of the Nuclear Study Centre of Saclay; an introduction to nuclear engineering; a study of the interaction of neutrons with various elements as a function of neutron velocity; a determination of the transport mean free path of thermal neutrons by measuring a complex length of diffusion; the electronic equipment used in the measurement of the diffusion length in graphite; the non destructive test of materials using the oscillation method in the Chatillon pile; an analogue harmonic analyser; recent progress in reactor control; analogue calculators pile simulators; the preparation of artificial radio-elements; the preparation of artificial radio-elements; a general review of radioactive survey equipment; radioactive aerosols and gases in the atomic industry; A fixed health monitoring installation at the High Activity Laboratory of Saclay. Reprint of a dossier published in 'L'Onde Electrique', Vol. XXXV, No. 343, October 1955, p. 783-947