WorldWideScience

Sample records for geologie chimie archeologie

  1. Mass spectrometry. Environment, biology, oenology, medicine, geology, chemistry, archaeology, mechanisms; Spectrometrie de masse. Environnement, biologie, oenologie, medecine, geologie, chimie, archeologie, mecanismes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    This document provides the papers (communications and posters) presented at the 16. French days of mass spectrometry, held September 6-9, 1999 in Nancy, France. 7 papers are interesting for the ETDE database and are analyzed separately. (O.M.)

  2. Mass spectrometry. Environment, biology, oenology, medicine, geology, chemistry, archaeology, mechanisms; Spectrometrie de masse. Environnement, biologie, oenologie, medecine, geologie, chimie, archeologie, mecanismes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    This document provides the papers (communications and posters) presented at the 16. French days of mass spectrometry, held September 6-9, 1999 in Nancy, France. 5 papers are interesting for the INIS database and are analyzed separately. (O.M.)

  3. Chimie des processus biologiques

    OpenAIRE

    Fontecave, Marc

    2010-01-01

    La chimie du vivant : enzymes et métalloenzymes, des biocatalyseurs fascinants La catalyse enzymatique, ce pouvoir que possèdent certaines protéines d’accélérer de façon extraordinaire et d’orienter avec une précision fascinante les réactions chimiques de la cellule, reste, encore aujourd’hui, l’un des grands mystères des systèmes vivants. Les réactions dont il est question vont de la simple hydrolyse de liaisons peptidiques à des processus poly-électroniques d’une très grande complexité, com...

  4. Reflexions, La Chimie Analytique Verte

    OpenAIRE

    Ziemons, Eric; Mantanus, Jérôme; Lebrun, Pierre; Rozet, Eric; Hubert, Philippe

    2008-01-01

    Au début des années 1990, est apparu le concept de “chimie verte” mieux connue sous le vocable anglais “Green Chemistry”. L’objectif principal de la chimie verte est de définir un cadre à la prévention de la pollution résultante des activités chimiques prises au sens le plus large. Dans ce contexte, une partie des travaux de recherche du Service de Chimie Analytique du Département de Pharmacie porte sur le développement de nouveaux outils pour la préparation et l’analyse d’échantillons. Pl...

  5. Chimis

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    StefaniChimjs公司致力于皮革染色、复鞣,磨革和涂饰产品的生产.目前在绒面革和磨砂革染色领域已处于领先地位。公司的专家团队可以为客户提供一流的服务。Stefani Chimis由Edgardo.Paolo和GiovanniStefani兄弟于1978年在Montebello Vicentino创建.其核心业务在意大利著名制革区阿尔齐尼亚诺。

  6. Chimie des interactions moléculaires

    OpenAIRE

    Lehn, Jean-Marie

    2010-01-01

    Le cours de l’année 2008-2009 a porté sur « Autoorganisation et dynamique moléculaires ». Des cours ont été donnés à l’Université de Strasbourg (3 h), à l’Université Charles de Prague (3 h) et à la City University de Hong Kong (3 h). Cours au Collège de France : Autoorganisation et dynamique moléculaires Introduction Le cours a porté sur l’évolution de la chimie supramoléculaire vers la chimie dynamique constitutionnelle (CDC) et la chimie adaptative. Du fait de la labilité des interactions n...

  7. Gemeinsame Aspekte und Probleme in Physik und Geologie

    Science.gov (United States)

    Watznauer, A.

    Die griechische Naturphilosophie, vor allem Aristoteles, verstand unter Physik die Naturwissenschaft in toto. Die Aufspaltung dieser universellen Naturphilosophie in Fachdisziplinen betrifft sowohl den Gegenstand als auch, daraus abgeleitet, die Methodik der Darstellung. Die Physik, deren Gegenstand seit Galilei die reinen Fälle sind, ist ahistorisch. Die Geologie, die komplexe Systeme untersucht, ist dagegen eine historische Wissenschaft.Translated AbstractCommon Aspects and Problems in Physics and GeologyThe greek philosophers and above all Aristotle thougt in the physics about nature in toto. The splitting of this philosophy of nature into different sciences concerns both their topics and their methods. Since Galilei physics is concerned with pure cases, being an ahistorical science. On the contrary geology examines complex systems, being of historical character.

  8. Chimie des matériaux hybrides

    OpenAIRE

    Sanchez, Clément

    2014-01-01

    Cours : chimie des matériaux hybrides Depuis plus d’une vingtaine d’années, les méthodes d’élaboration de nanomatériaux inorganiques ou hybrides reposant sur la « chimie douce » suscitent un très fort intérêt, aussi bien dans le monde universitaire qu’industriel. Ces méthodes de synthèse mettent en jeu des réactions de « polymérisation » au sens large s’effectuant à température ambiante, en solvant aqueux ou organique, à partir de précurseurs moléculaires ou nanoparticulaires. Ces conditions ...

  9. 2011 : Année internationale de la chimie

    OpenAIRE

    2011-01-01

    Lors de la 63e assemblée générale des Nations Unies, 2011 a été proclamée année internationale de la chimie. En France, les acteurs de la chimie sont mobilisés pour promouvoir quatre objectifs : mettre l’accent sur l’importance de la chimie pour un développement durable dans tous les aspects de la vie sur la planète ; accroître chez les jeunes l’intérêt pour la chimie ; susciter l’enthousiasme pour une chimie tournée vers l’avenir ; célébrer les travaux de Marie Curie et la contribution des f...

  10. Kiezen van Nederlandsche Elephantidae, aanwezig in het Rijksmuseum van Geologie en Mineralogie

    NARCIS (Netherlands)

    Zonneveld, J.I.S.

    1942-01-01

    In this paper we described the molar teeth of E. primigenius found in our country and stored in the Rijksmuseum van Geologie en Mineralogie at Leyden. Special attention is paid to the individual age of the animals at the moment when the grinders were rendered inoparative. As a rule this must have ta

  11. Die Geologie von Camarena de la Sierra und Riodeva (Provinz Teruel, Spanien)

    NARCIS (Netherlands)

    Wz., R. Martin

    1936-01-01

    Als ich im Jahre 1933 ein Gebiet für meine Feldarbeit suchte, wählte ich auf Veranlassung von Herrn Dr. I. M. van der Vlerk die Gemeinde Camarena de la Sierra südlich von Teruel, wo G. R. J. Terpstra, damals Student der Geologie zu Leiden, im Sommer 1931 eine geologische Aufnahme angefangen hatte,

  12. Die Geologie von Camarena de la Sierra und Riodeva (Provinz Teruel, Spanien)

    NARCIS (Netherlands)

    Wz., R. Martin

    1936-01-01

    Als ich im Jahre 1933 ein Gebiet für meine Feldarbeit suchte, wählte ich auf Veranlassung von Herrn Dr. I. M. van der Vlerk die Gemeinde Camarena de la Sierra südlich von Teruel, wo G. R. J. Terpstra, damals Student der Geologie zu Leiden, im Sommer 1931 eine geologische Aufnahme angefangen hatte, w

  13. Meeting of the French geological society - Uranium: geology, geophysics, chemistry. Book of abstracts; Reunion de la Societe Geologique de France - Uranium: geologie, geophysique, chimie. Recueil des resumes

    Energy Technology Data Exchange (ETDEWEB)

    Zakari, A.A.; Mima, S.; Bidaud, A.; Criqui, P.; Menanteau, P.; David, S.; Pagel, M.; Chagnes, A.; Cote, G.; Courtaud, B.; Thiry, J.; Miehe, J.M.; Gilbert, F.; Cuney, M.; Bruneton, P.; Ewington, D.; Vautrin-Ul, C.; Cannizzo, C.; Betelu, S.; Chausse, A.; Ly, J.; Bourgeois, D.; Maynadie, J.; Meyer, D.; Clavier, N.; Costin, D.T.; Cretaz, F.; Szenknect, S.; Ravaux, J.; Poinssot, C.; Dacheux, N.; Durupt, N.; Blanvillain, J.J.; Geffroy, F.; Aparicio, B.; Dubessy, J.; Nguyen-Trung, C.; Robert, P.; Uri, F.; Beaufort, D.; Lescuyer, J.L.; Morichon, E.; Allard, T.; Milesi, J.P.; Richard, A.; Rozsypal, C.; Mercadier, J.; Banks, D.A.; Boiron, M.C.; Cathelineau, M.; Dardel, J.; Billon, S.; Patrier, P.; Wattinne, A.; Vanderhaeghe, O.; Fabre, C.; Castillo, M.; Salvi, S.; Beziat, D.; Williams-Jones, A.E.; Trap, P.; Durand, C.; Goncalves, P.; Marquer, D.; Feybesse, J.L.; Richard, Y.; Orberger, B.; Hofmann, A.; Megneng, M.; Orberger, B.; Bouttemy, M.; Vigneron, J.; Etcheberry, A.; Perdicakis, M.; Prignon, N.; Toe, W.; Andre-Mayer, A.S.; Eglinger, A.; Jordaan, T.; Hocquet, S.; Ledru, P.; Selezneva, V.; Vendryes, G.; Lach, P.; Cuney, M.; Mercadier, J.; Brouand, M.; Duran, C.; Seydoux-Guillaume, A.M.; Bingen, B.; Parseval, P. de; Guillaume, D.; Bosse, V.; Paquette, J.L.; Ingrin, J.; Montel, J.M.; Giot, R.; Maucotel, F.; Hubert, S.; Gautheron, C.; Tassan-Got, L.; Pagel, M.; Barbarand, J.; Cuney, M.; Lach, P.; Bonhoure, J.; Leisen, M.; Kister, P.; Salaun, A.; Villemant, B.; Gerard, M.; Komorowski, J.C.; Michel, A.; Riegler, T.; Tartese, R.; Boulvais, P.; Poujols, M.; Gloaguen, E.; Mazzanti, M.; Mougel, V.; Nocton, G.; Biswas, B.; Pecaut, J.; Othmane, G.; Menguy, N.; Vercouter, T.; Morin, G.; Galoisy, L.; Calas, G.; Fayek, M.

    2010-11-15

    This document brings together the abstracts of the 39 presentations given at this meeting days on uranium, organized by the French geological society, and dealing with: 1 - Prospective study of the electronuclear technological transition; 2 - The front-end of the nuclear cycle: from the molecule to the process; 3 - Geophysics: recent changes; 4 - Use of well logging in uranium exploration; 5 - Genetical classification of thorium deposits; 6 - Genetical nomenclature of uranium sources; 7 - Uranium deposits linked to a Proterozoic discordance - retrospective; 8 - The use of spectral analysis techniques in uranium exploration: real-time mapping of clay alteration features; 9 - Development of functionalized silk-screened carbon electrodes for the analysis of uranium trace amounts; 10 - Study of the actinides solvation sphere in organic environment; 11 - Thermodynamic of uraniferous phases of interest for the nuclear cycle; 12 - Heap leaching of marginal minerals at Somair: from lab studies to the production of 700 t of uranium/year; 13 - Agglomeration phenomenology and role of iron in uranium heap leaching; 14 - Chloride uranyl complexes up to 300 deg. C along the saturation vapour curve: Raman spectroscopy analysis and metallogenic consequences; 15 - Weathering systems in the Shea Creek deposit (Athabasca, Canada): vertical variability of argillaceous weathering; 16 - Weathering systems in the Shea Creek deposit (Athabasca, Canada): contribution of irradiation defects in clays to the tracing of past uranium migrations; 17 - Uranium concentrations in mineralizing fluids of the Athabasca basin: analytical and experimental approach; 18 - Paleo-surfaces and metallic rooting: the autochthonous uranium of pre-Athabasca paleo-alterites, Canada; 19 - Distribution of argillaceous parageneses in the Imouraren deposit - Niger; 20 - Heat flux and radioelements concentration (U, Th, K) of precambrian basements: implications in terms of crust growth mechanisms, paleo-temperature, and metallogenic provinces; 21 - Magmatic-hydrothermal transition in the Roessing pegmatite: implications for uranium mineralisation; 22 - Deformation and partial fusion of a Archean-paleo-Proterozoic crust: implication on uraniferous ores mobilization and deposition, Torngats orogenesis, Ungava bay; 23 - Black chert pebbles of the Pongola basin conglomerates ({approx}2, 9 Ga - South Africa): a potential uranium source?; 24 - origin and evolution of detrital pyrites in meso-Archean conglomerates (3.08-2.64 Ga) of South Africa: uranium source or trap?; 25 - Experimental study of U(VI) carbonates with respect to 3 parameters: pH, carbonate concentration, temperature, using vibrational (Raman, FTIR, ATR) and optical (UV-visible) spectroscopy; 26 - Nature and significance of the contact between the Abbabis gneiss complex and the meta-sedimentary sequences of the Damara orogenic belt; 27 - Metallogenic potentialities of Proterozoic orogenic belts accreted to Archean basements: the Damara/Lufilien orogen - Namibia and Zambia; 28 - Contribution of the Geological Exploration to the development of the KATCO ISR mine - Chu-Sarysu basin, Kazakhstan; 29 - Remarks about some remarkable events which occurred during the Francevillien formation; 30 - Geochemical signature of different mineral phases obtained by ICP-MS laser ablation (trace elements and rare earths): Application Uranium deposits; 31 - Role of fluids and irradiation in complex pegmatite euxenite/zircon assemblies from Norway and their U-Pb geochronological consequences; 32 - Mechanical modeling of rupture around metamictic minerals; 33 - Helium diffusion in apatite: Effect alpha recoil-linked damages; 34 - Rare earth spectra in uranium oxides: a marker of the uranium deposit type; 35 - Rare earths: tracers of uranium behaviour during acid sulphated hydrothermal weathering - the Guadeloupe example; 36 - What metallogenic model for the Kiggavik-Andrew Lake trend? Nunavut, Canada; 37 - Uranium mobility in the Southern Armorican system; 38 - Uranium Clusters: Models for Environmentally Relevant Species; 39 - Uranium speciation in Nopal I opals - Sierra Pena Blanca, Mexico

  14. La Chimie Biologique Industrielle à Gembloux Agro-Bio Tech

    OpenAIRE

    Berchem, Thomas; Istasse, Thibaut; Schmetz, Quentin; Jacquet, Nicolas; Richel, Aurore

    2016-01-01

    Présentation du laboratoire de Chimie Biologique Industrielle et illustration de nos principales activités; point sur les recherches de trois jeunes doctorants. Leur travail consiste en la valorisation de matrices biologiques (déchets agricoles, industriels et forestiers,...) pour produire une gamme de nouveaux produits, biocarburants ou molécules chimiques.

  15. La chimie dans tous ses états

    OpenAIRE

    Ruiz-Hitzky,Eduardo

    2015-01-01

    1. Le four à micro-ondes : de la cuisine à la chimie de synthèse Un four à micro-ondes est un appareil électroménager utilisé principalement pour le chauffage rapide d’aliments, par agitation des molécules d’eau qu’ils contiennent sous l’effet d’un rayonnement micro-onde (Wikipédia). Dès les débuts, cette technologie fut principalement utilisée dans la cuisine et éventuellement dans des applications industrielles très précises, mais depuis une vingtaine d’années les fours à micro-ondes sont ...

  16. Compte rendu de : Luc Peterschmitt, Berkeley et la chimie. Une philosophie pour la chimie au XVIIIe siècle

    OpenAIRE

    François Pépin

    2014-01-01

    Ce livre, issu d’une thèse de doctorat sur Berkeley et les sciences, constitue la première étude systématique des rapports entre Berkeley et la chimie. C’est aussi une tentative originale pour examiner la cohérence et la pertinence d’un des derniers textes de Berkeley, la Siris, souvent considérée comme un ouvrage mineur, voire comme une erreur de vieillesse. Ces deux projets novateurs se croisent, puisque c’est par la philosophie de la chimie que Luc Peterschmitt cherche à montrer l’intérêt ...

  17. Compte rendu de : Luc Peterschmitt, Berkeley et la chimie. Une philosophie pour la chimie au XVIIIe siècle

    Directory of Open Access Journals (Sweden)

    François Pépin

    2012-03-01

    Full Text Available Ce livre, issu d’une thèse de doctorat sur Berkeley et les sciences, constitue la première étude systématique des rapports entre Berkeley et la chimie. C’est aussi une tentative originale pour examiner la cohérence et la pertinence d’un des derniers textes de Berkeley, la Siris, souvent considérée comme un ouvrage mineur, voire comme une erreur de vieillesse. Ces deux projets novateurs se croisent, puisque c’est par la philosophie de la chimie que Luc Peterschmitt cherche à montrer l’intérêt ...

  18. Natural and anthropogenic environmental hazards. Research results of the Department of Applied Geology; Natuerliche und anthropogene Umweltgefaehrdungen. Forschungsergebnisse aus dem Lehrstuhl fuer Angewandte Geologie

    Energy Technology Data Exchange (ETDEWEB)

    Czurda, K.; Eiswirth, M.; Hoetzl, H. [comps.

    1998-12-31

    Applied geology is employed in mining geology, raw materials geology, engineering geology, and hydrogeology, of which the two last-mentioned are the most important for the Department of Applied Geology. This series of publications arose from the need of making research findings, dissertations, theses and conference papers accessible to the public faster and more comprehensively than in national and international journals. [Deutsch] Die Aufgaben der angewandten Geologie sind im weitesten Sinne in der Montangeologie, in der Rohstoffgeologie, in der Ingenieurgeologie und in der Hydrogeologie zu sehen. Der engere Aufgabenbereich der Institute fuer Angewandte Geologie konzentriert sich der heutigen Fragestellung entsprechend meist auf die Ingenieurgeologie und Hydrogeologie. Wenn wir daraus noch die Umweltgeologie ableiten, so ist der Lehr- und Forschungsschwerpunkt auch des Karlsruher Lehrstuhles fuer Angewandte Geologie (AGK=Angewandte Geologie Karlsruhe) umrissen. Die vorliegende Schriftenreihe ist aus der Notwendigkeit entstanden, Forschungsergebnisse, Dissertationen und ausgewaehlte Diplomarbeiten sowie Beitraege einschlaegiger Tagungen in Karlsruhe rascher und u.U. umfangreicher als in internationalen oder nationalen Journalen moeglich zu publizieren. (orig.)

  19. [Précis de chimie organique (1844-1846) and the Traité de chimie organique (1853-1856) from Charles Gerhardt].

    Science.gov (United States)

    Delort, Marie

    2007-07-01

    In 1844 and in 1853 Charles Gerhardt writes two textbooks about organic chemistry: Précis de chimie organique and Traité de chimie organique. In these textbooks Gerhard presents a way to arrange organic compounds in series. The Traité is more accomplished. The classification has improved. His idea is that all organic compounds are based on four main types (i.e., hydrogen, hydrogen chloride, ammonia, and water). Why did Gerhardt chose to develop his theories in a textbook and not in scientific papers? We can think of a few reasons: in a textbook he could articulate ideas and could give constitency to his theories. It is longer than a paper. Textbook authors are less rescricted. The readers are students.

  20. Fontenelle et la chimie : la recherche d’une « loi fondamentale » pour la chimie

    Directory of Open Access Journals (Sweden)

    Luc Peterschmitt

    2012-03-01

    Full Text Available Dans cet article, je propose de reprendre la position de Fontenelle à l’endroit de la chimie. C’est une science qu’il connaît mal avant de devenir Secrétaire de l’Académie Royale des Sciences, et dont il doit, comme Secrétaire de l’institution, chercher une légitimité qu’il a contesté à titre personnel. Or la façon dont il rend compte des mémoires de chimie montre que Fontenelle accompagne l’évolution de cette science à partir de 1699, en se montrant ouvert à ce qu’elle propose de nouveauté. Certes, il rejette ce qu’il identifie comme chimie ancienne, en coupant ainsi la chimie du début du 18e siècle de son histoire. Cette opération rhétorique ne doit pas tromper et ne signifie pas qu’il considère que la chimie qui se fait sous ses yeux n’est pas un savoir. Au contraire, il salue ce qui la met sur la voie de la science. Cela le conduit sans doute à insister sur tous les éléments mécanistes utilisés par certains chimistes. S’en tenir là reviendrait toutefois à manquer son importante réflexion sur les affinités à partir de 1718 : pour Fontenelle, elles donnent la « loi fondamentale » de la chimie. La recherche des affinités, en tant qu’elles sont distinctes de l’attraction newtonienne ou des anciennes sympathies occultes, instituent pour Fontenelle la chimie comme une science de plein droit, même si elle échappe à l’explication mécaniste.In this paper, my aim is to reexamine Fontenelle’s position as to chemistry. Before he became the Secretary of the Académie Royale des Sciences of Paris, Fontenelle knew chemistry quite badly and he ridiculed it in his personal works; but as the Secretary of the institution he has to justify its existence a science. The way in which he accounts for the memoirs of chemistry shows that Fontenelle follows the evolution of this science from 1699, proving that he is aware of its novelties. Of course, Fontenelle keeps rejecting what he identifies

  1. L’importance de la loi de volumes pour le développement de la Chimie Organique

    OpenAIRE

    Camel, Tania

    2014-01-01

    L’époque post-révolutionnaire est une période de l’Histoire de la Chimie où des contributions très importantes ont lieu, même si cette période ne bénéficie pas toujours de l’attention qu’elle mérite quand on aborde l’histoire de la chimie au XIXe siècle. Durant les trente premières années, il y a eu des changements significatifs dans le domaine de la Chimie Organique qui sont directement liés au travail de Gay-Lussac (1778-1850). Cet article veut montrer l’importance de la loi des volumes des...

  2. Analyse de l'activité des enseignants de chimie organique autour du contenu enseigné

    OpenAIRE

    Lafarge, David; Morge, Ludovic; Méheut, Martine

    2009-01-01

    http://ardist.aix-mrs.iufm.fr/wp-content/textes%20communications/16_Lafarge%20D; International audience; La chimie organique est souvent reconnue comme une discipline difficile à enseigner et à apprendre. Pour comprendre l'origine de cette difficulté nous avons étudié l'activité des enseignants de chimie organique jusqu'à bac+2. Nos résultats montrent que la structuration des contenus est très répandue (principaux outils théoriques, puis principales familles de molécules), la stratégie de syn...

  3. La chimie du XVIIe siècle : une question de principes

    Directory of Open Access Journals (Sweden)

    Rémi Franckowiak

    2008-04-01

    Full Text Available Le tournant du XVIIe au XVIIIe siècle est une période décisive pour l’histoire de la chimie qui passe de la reconnaissance institutionnelle à la contestation de son fondement théorique, pour apparaître au final comme la seule partie de la Physique à pouvoir prétendre atteindre la « vérité certaine ». Ce qui se joue alors n’est rien de moins que la redéfinition de ses principes, à savoir son socle de vérités sur lequel s’appuie la science chimique. Cette période est en fait la dernière étape de l’évolution du rapport entre les deux dimensions – théorique et pratique – dans lesquelles se déploie la chimie, qui a vu, par le développement de l’usage des principes dits seconds, l’ensemble des principes chimiques entrainé vers un réalisme empirique, ayant pour effet d’ôter de la chimie toute cohérence théorique. Aussi l’apparition du mécanisme – pas plus celui de Boyle – n’est-il en réalité responsable du bouleversement que connaît la chimie ; elle n’est pas davantage responsable de sa régénération au tout début du XVIIIe siècle. La conscience de la faiblesse théorique de la chimie va devenir pour elle promesse de vigueur théorique sur la base de ce qui représente sa force : l’expérience. À la suite de la perte de ce qui fut certitude, le chimiste devient un être à ré-instruire. Un chimiste tel que Samuel Cottereau Du Clos illustre parfaitement le passage d’une science chimique comme connaissance des principes à une chimie comme science cette fois du vraisemblable.The last decades of 17th century represent a decisive period for the history of Chemistry which switched from institutional recognition to dispute of its theoretical basis, to seem finally, during the very first years of the next century, the only part of Physics being able to claim reaching the “unquestionable truth”. What did happen then is nothing less than the redefinition of principles of Chemistry

  4. Les Nobel juifs de chimie le partage du savoir au XX siècle

    CERN Document Server

    Benguigui, Isaac

    2010-01-01

    L'un des traits marquants et remarquables des Juifs tout au long de leur histoire, plusieurs fois millénaire, a été leur créativité dans tous les domaines, en particulier dans le domaine scientifique. Ils ont participé de façon impressionnante à la remise en cause des valeurs, au démantèlement des dogmes et à l'irruption des forces cachées. On peut d'emblée souligner que la contribution des Juifs à la science a été sans commune mesure avec le pourcentage de la population qu'ils représentent. Cela reste vrai pour la chimie du XXe siècle. A travers la vie et l'oeuvre de 23 prix Nobel de chimie, l'auteur nous livre une histoire passionnante de ces hommes, biens souvent des exilés et d'origine modeste. dont la science fut leur vocation et le partage du savoir leur crédo.

  5. Fontenelle, l’Académie et le devenir scientifique de la chimie

    Directory of Open Access Journals (Sweden)

    François Pépin

    2012-02-01

    Full Text Available Cet article part du point de vue de Fontenelle pour aborder le devenir scientifique de la chimie au sein de l’Académie de la fin du XVIIe siècle à la première moitié du XVIIIe siècle. Contre la vision traditionnelle d’un Fontenelle cartésien centré sur les mathématiques et la physique, le travail du Secrétaire perpétuel de l’Académie Royale des Sciences montre un intérêt réel pour la chimie et les chimistes, ainsi qu’un regard éclairant sur la diversité, les continuités et les évolutions des chimies pratiquées à l’Académie. La confrontation des comptes rendus et des éloges de Fontenelle avec les mémoires des savants révèle une mise en perspective remarquable, à la fois historique et épistémologique, qui souligne la spécificité de la chimie tout en l’articulant avec les autres sciences – notamment la physique. Pluralisant les approches, Fontenelle joue subtilement avec les catégories de la rupture et de la continuité, de la pluralité des pratiques scientifiques et de l’unité d’un horizon commun. Il construit ainsi, non un récit continu de l’évolution de la chimie académique, mais l’image nuancée d’un devenir complexe et pluriel.This paper considers Fontenelle’s point of view about the scientific evolution of chemistry in the Academy from the end of the 17th century to the first part of the 18th century. Against the traditional idea that Fontenelle was a Cartesian only concerned with mathematics and physics, his work as the Perpetual Secretary of the Royal Academy of Sciences demonstrates a real interest in chemistry and chemists. His work also sheds light on the diversity, the continuities and the evolutions of the various kinds of chemistry practiced in the Academy. The comparison of Fontenelle’s reviews and panegyrics with scientists’ memoirs shows an original historical and epistemological perspective, underlying the specificity of chemistry without separating it from other

  6. Chimie des neiges et glaces antarctiques : un reflet de l'environnement

    OpenAIRE

    Legrand, Michel

    1985-01-01

    Le but de ce travail était d'étudier la partie soluble (soit plus de 90% du total) des impuretés contenues dans les neige et glace antarctiques, afin de mieux comprendre la chimie atmosphérique actuelle et passée de la Terre. Grâce à 2 techniques nouvelles (la mesure de la teneur en H+, encore appelée acidité forte, et la chromatographie ionique) que nous avons adaptées à l'étude des traces, nous avons pu étudier de manière systématique cette partie soluble des impuretés. Après avoir résolu l...

  7. [The "Journal de Pharmacie et de Chimie" and the two world wars].

    Science.gov (United States)

    Bonnemain, Bruno

    2011-02-01

    The "Journal de Pharmacie et de Chimie" was the official publication of the Société de Pharmacie de Paris which became later on the French Academy of pharmacy. It is consequently the organ that presented scientific publications and independent position papers from pharmacists being part of this assembly and coming from universities, drugstores or pharmaceutical industries. We have analyzed the content of this journal during the last two world wars in order to evaluate to what extent the members of the Société de Pharmacie de Paris were part of the war efforts, and encouraged or criticized the on-going events. We can observe that, in both cases, pharmacists used their expert opinions to better react and manage consequences of the conflicts, but also to express their disagreement with enemy's opinions or actions, the Society doing everything possible to maintain its activities. One can observe also that both conflicts were an opportunity to reconsider the organization of pharmacy in France, especially during the Second World War where took place discussions on pharmacy reform (1941 law) and creation of the Pharmacists' Order which will ultimately occur after the war end.

  8. Silver Vanadium Phosphorous Oxide, Ag(2)VO(2)PO(4): Chimie Douce Preparation and Resulting Lithium Cell Electrochemistry.

    Science.gov (United States)

    Kim, Young Jin; Marschilok, Amy C; Takeuchi, Kenneth J; Takeuchi, Esther S

    2011-08-15

    Recently, we have shown silver vanadium phosphorous oxide (Ag(2)VO(2)PO(4), SVPO) to be a promising cathode material for lithium based batteries. Whereas the first reported preparation of SVPO employed an elevated pressure, hydrothermal approach, we report herein a novel ambient pressure synthesis method to prepare SVPO, where our chimie douce preparation is readily scalable and provides material with a smaller, more consistent particle size and higher surface area relative to SVPO prepared via the hydrothermal method. Lithium electrochemical cells utilizing SVPO cathodes made by our new process show improved power capability under constant current and pulse conditions over cells containing cathode from SVPO prepared via the hydrothermal method.

  9. Wilhelm Homberg et la chimie de la lumière

    Directory of Open Access Journals (Sweden)

    Lawrence M. Principe

    2008-03-01

    Full Text Available En 1705, Wilhem Homberg, le principal chimiste de l’Académie royale des sciences, proposa une nouvelle théorie chimique selon laquelle le Soufre principe des corps mixtes était identique à la lumière. Il affirma par la suite que cette lumière corporelle était la seule source d’activité et de changement dans les substances matérielles. Cet article montre comment la théorie de Homberg s’élabora progressivement pendant de nombreuses années sous l’influence de ses observations et des résultats de ses expériences de laboratoire, ce qui nous fournit un exemple de la manière selon laquelle un chimiste du début du XVIIIe siècle a pu développer une théorie raffinée grâce à l’interaction de la réflexion et de la manipulation. L’influence probable de la théorie de Homberg sur les fameuses « questions chimiques » de Newton est également signalée ici pour la première fois. Enfin l’article avance que nous comprendrons plus précisément l’histoire de la chimie si nous reconnaissons le caractère spécifique de la chimie et sa relative autonomie, plutôt que si nous cherchons à lui imposer des développements faciles et convenus tirés d’autres champs du savoir comme la philosophie ou la physique.In 1705, Wilhelm Homberg, the chief chemist of the Académie Royale des Sciences, proposed a new chemical theory that the Sulphur principle of mixed bodies was identical with light. He claimed further that this embodied light was the sole source of activity and change in material substances. This paper traces how Homberg’s theory emerged gradually over many years under the influence of his observations and the results of his laboratory experiments. It thus provides an example of how an early eighteenth-century chemist developed a sophisticated theory through the interplay of mind and hand. The probable influence of Homberg’s theory on Isaac Newton’s famous “chymical queries” is also noted here for the first

  10. The geology of uranium in the Saint-Sylvestre granite district (Limousin, Massif Central, France); La geologie de l'uranium dans le massif granitique de Saint-Sylvestre (Limousin - Massif Central Francais)

    Energy Technology Data Exchange (ETDEWEB)

    Marquaire, C.; Moreau, M.; Barbier, J.; Ranchin, G.; Carrat, H.G.; Coppens, R.; Senecal, J.; Koszotolanyi, C.; Dottin, H

    1969-07-01

    This report concerns the geology of uranium in Limousin, more particularly in the St-Sylvestre massif, and the related phenomena: regional geology, petrographic and geochemical zonal distribution observed in various granite massifs, uranium movement in connection with surface alteration, geochronology of uranium ore. The work is made up of six articles covering the various scientific aspects listed above. Each article is headed with an abstract. The paper comprises the following chapters: Foreword by Marcel ROUBAULT. 1. Ch. MARQUAIRE, M. MOREAU Outline of geological conditions in Northern Limousin and distribution of uraniferous occurrences. 2. J. BARBIER, G. RANCHIN, H. G. CARRAT and R. COPPENS Geology of the St-Sylvestre Massif and uranium geochemistry - Introduction to laboratory studies - Problems of methodology. 3. J. BARBIER and G. RANCHIN Petrographical and geochemical zones in the St-Sylvestre granite massif (Limousin - French 'Massif Central'). 4. J. BARBIER and G. RANCHIN Uranium geochemistry in the St-Sylvestre Massif (Limousin - French 'Massif Central') - Occurrences of primary geochemical uranium and replacement processes. 5. J. SENEGAL Monograph of the Brugeaud orebody. 6. R. COPPENS, Ch. KOSZTOLANYI and H. DOTTIN Geochronological study of the Brugeaud mine. 1969. (authors) [French] Ce memoire est consacre a la geologie de l'uranium dans le Limousin, plus specialement dans le massif de St-Sylvestre, et aux phenomenes qui s'y rattachent: geologie regionale, phenomenes de zonalite petrographique et geochimique dans certains massifs granitiques, mouvements de l'uranium lies a l'alteration superficielle, geochronologie du minerai d'uranium. L'ouvrage comprend six articles qui recouvrent les differents aspects scientifiques enumeres. Chacun de ces six articles est precede d'un resume. La composition du memoire st la suivante: Marcel ROUBAULT, Preface. 1. Ch. MARQUAIRE, M. MOREAU Esquisse geologique du

  11. Le four micro-ondes : de la cuisine à la chimie de synthèse

    OpenAIRE

    Ruiz-Hitzky,Eduardo

    2014-01-01

    Le four micro-ondes : de la cuisine à la chimie de synthèse La définition du four micro-ondes octroyée par Wikipédia est la suivante : Un four à micro-ondes est un appareil électroménager utilisé principalement pour le chauffage rapide d’aliments, par agitation des molécules d’eau qu’ils contiennent sous l’effet d’un rayonnement micro-onde. Mais si, dès les débuts, cette technologie fut principalement utilisée dans la cuisine et éventuellement dans des applications industrielles très précises...

  12. Synthèses par chimie douce de fluorures dopés terres rares pour applications optiques

    OpenAIRE

    Labeguerie-Egea, Jessica

    2007-01-01

    Cette thèse, consacrée à la synthèse de fluorures dopés par des ions de terres rares par chimie douce, a fait l'objet de deux types de synthèses particulières : la synthèse sol-gel et la synthèse par micelles inverses, toutes deux réalisées dans des milieux non-aqueux. La synthèse sol-gel, consistant en la dissolution d'acétates métalliques dans de l'acide trifluoroacétique et de l'isopropanol, a été mise en œuvre afin de réaliser des guides d'ondes amplificateurs à 1.54 μm grâce au dopage à ...

  13. La micro-échelle en synthèse organique : un outil commun chimie/génie chimique

    OpenAIRE

    Prat, Laurent E.; Loubiere, Karine; Dechy-Cabaret, Odile

    2014-01-01

    National audience; Cet article est une restitution courte de la présentation réalisée au cours des JIREC 2013 sur l'enseignement de la notion de changement d'échelle et de passage d'un mode batch à un mode continu en synthèse organique. L'enjeu est de faire travailler des étudiants issus des départements chimie et génie chimique autour d'un même outil, le microréacteur. Au cours d'une séance de travaux pratiques, les étudiants mettent en oeuvre une synthèse organique en continu à micro-échell...

  14. ACDV, Association Chimie du Végétal : une initiative française pour développer la chimie du végétal

    Directory of Open Access Journals (Sweden)

    Friès Aurore

    2013-01-01

    Full Text Available Industry dependence on external fossil fuel resources, fluctuations in energy and raw materials costs, climate change, environmental regulations, changing consumer attitudes etc. In France, where agriculture and the chemical industry are two pillars of the economy, these harsh realities have prompted the chemical and agro-resources sectors to look to biobased chemistry as a means of diversifying outlets for biomass and chemical sourcing, with the aim of balanced use. French players in this international sector have realised the value of joining forces, pooling skills, knowhow and resources into a single structure to drive forward the development of biobased chemistry. This shared vision and determination resulted in the creation in 2008 of the French biobased chemistry association, Association Chimie du V_eg_etal (ACDV. This initiative, still the first of its kind, brings together within a single federation all those directly involved in biobased chemistry. ACDV’s stated aim: to propose and create industrial, economic and political conditions conducive to the development of this industrial reality, within a context of competitive, responsible and sustainable agricultural and chemical sectors. ACDV acts as a source of creative ideas, presenting national and European bodies with the strategic vision and position of French industrialists as regards the international development and competitiveness of biobased chemistry. A commitment by the French chemicals industry to a target of 15% biobased raw materials by 2017 is one of the key factors underpinning the work of the ACDV.

  15. Electrochemical fluorination of La(2)CuO(4): a mild "chimie douce" route to superconducting oxyfluoride materials.

    Science.gov (United States)

    Delville, M H; Barbut, D; Wattiaux, A; Bassat, J M; Ménétrier, M; Labrugère, C; Grenier, J C; Etourneau, J

    2009-08-17

    The fluorination of La(2)CuO(4) was achieved for the first time under normal conditions of pressure and temperature (1 MPa and 298 K) via electrochemical insertion in organic fluorinated electrolytes and led to lanthanum oxyfluorides of general formula La(2)CuO(4)F(x). Analyses showed that, underneath a very thin layer of LaF(3) (a few atomic layers), fluorine is effectively inserted in the material's structure. The fluorination strongly modifies the lanthanum environment, whereas very little modification is observed on copper, suggesting an insertion in the La(2)O(2) blocks of the structure. In all cases, fluorine insertion breaks the translation symmetry and introduces a long-distance disorder, as shown by electron spin resonance. These results highlight the efficiency of electrochemistry as a new "chimie douce" type fluorination technique for solid-state materials. Performed at room temperature, it additionally does not require any specific experimental care. The choice of the electrolytic medium is crucial with regard to the fluorine insertion rate as well as the material deterioration. Successful application of this technique to the well-known La(2)CuO(4) material provides a basis for further syntheses from other oxides.

  16. Geology and hydrocarbon concentrations of the Permian strata in the eastern section of the North German Basin; Zur Geologie und Kohlenwasserstoff-Fuehrung des Perm im Ostteil der Norddeutschen Senke

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, E.P. [comp.; Porth, H. [comp.

    1993-12-31

    Between World War II and the German unification, East Germany made intensive effects in petroleum and natural gas prospecting. More than 2000 exploratory boreholes were drilled, most of them in the Zechstein and Rotliegendes but also in the pre-Permian underground. The analyses of sites and drill cores provided an excellent database of the geology and hydrocarbon concentrations of deep underground formations in East Germany. Little was published of the exploration results, and no detailed information on petroleum geology or economic aspects was made available to the public or to experts in West Germany. The first exchange of information took place in 1989 at Brunswick during a symposium of the Academy of Geosciences of Niedersachsen. 6 papers of the symposium at Zinnowitz in November 1990 are available as separate records in this database. (orig./HS) [Deutsch] In den Jahrzehnten zwischen Kriegsende und der Vereinigung der beiden deutschen Staaten wurde in der ehemaligen DDR intensiv auf Erdoel und Erdgas gebohrt. Es wurden ueber 2000 Bohrungen, vornehmlich auf Zechstein und Rotliegendes, aber auch auf den praepermischen Untergrund, niedergebracht. Durch die intensive wissenschaftliche Bearbeitung der Bohrungen und des umfangreichen Kernmaterials wurde eine exzellente Datenbasis ueber die Geologie und KW-Fuehrung des tieferen Untergrundes Ostdeutschlands geschaffen. Ueber die Ergebnisse dieser intensiven Exploration wurde relativ wenig publiziert, und dies meist in allgemeiner Form. Erdoelgeologische Detailinformationen oder gar Untersuchungsergebnisse von wirtschaftlicher Relevanz gelangten nicht in die Oeffentlichkeit und damit auch nicht ins westliche Deutschland. Ein erster Meilenstein auf dem Weg zu einem normalen Erfahrungsaustausch zwischen den Erdoelgeologen aus Ost und West war das Symposium der Niedersaechsischen Akademie fuer Geowissenschaften im Oktober 1989 in Braunschweig, wo von ostdeutschen Kollegen erstmalig fuer ein westdeutsches Auditorium ein

  17. La modelisation mathematique dans l'enseignement de la chimie des gaz a des eleves de la cinquieme annee du secondaire

    Science.gov (United States)

    Gauthier, Diane

    Les problemes d'enseignement de la chimie des gaz parfaits sont donc importants. Si plusieurs etudes ont ete realisees dans le but d'identifier et d'interpreter ces problemes, aucune recherche, a notre connaissance, n'a ete realisee sur l'enseignement des lois sur les gaz parfaits. Notre recherche sur l'enseignement est donc pionniere. Elle a pour objectif general de construire et d'analyser une sequence d'enseignement de la chimie des gaz comportant diverses situations de modelisation mathematique des conduites des gaz. Les principaux objectifs specifiques sont les suivants: (1) identifier et caracteriser les situations qui provoquent une evolution des conceptions naives des eleves, evolution vers des connaissances plus adequate sur les gaz; (2) identifier et caractEriser les situations qui provoquent une evolution des connaissances mathematiques des eleves leur permettant d'interpreter convenablement les resultats des experiences, d'eprouver leurs conceptions, de donner un sens aux notions et aux relations impliquees dans les lois des gaz parfaits, lois de Boyle-Mariotte et Gay-Lussac. Une sequence d'enseignement comportant huit situations est d'eleves de secondaire V. La construction de ces situations est orientee par les recherches sur les conceptions naives des eleves, par les etudes sur l'evolution historique des conceptions sur les gaz et des pratiques scientifiques, ainsi que par les etudes theoriques et empiriques realisees en didactique des sciences et des mathematiques. La methodologie de l'ingenierie didactique (Artigue, 1998) qui constitue une application de la theorie des situations didactiques (Brousseau, 1986) est utilisee dans la construction et l'analyse des situations d'enseignement. Une analyse a priori de chacune des situations d'enseignement est effectuee; elle a pour but dexpliquer les choix des taches qui font partie des situations et de preciser la gestion didactique des situations. Diverses situations d'enseignement de la chimie ont ainsi

  18. D’une science à l’autre : Chimie et manuscrits médiévaux. Étapes d’une évolution

    Directory of Open Access Journals (Sweden)

    Claude Coupry

    2006-09-01

    Full Text Available C’est avec le Centre d’études médiévales d’Auxerre que s’établit dès 1986 ma première participation à une équipe de recherche en histoire médiévale. Et pourtant, rien dans ma formation initiale, thèse de Troisième Cycle en Chimie Physique, ni dans le premier poste que j’ai occupé dans le Laboratoire de Spectrochimie Infrarouge et Raman du CNRS, ne suggérait un quelconque lien avec le Moyen Âge. Technique, objet d’étude et finalité de ces recherches se situaient dans le domaine de la physico-c...

  19. Mesures in situ et à haute fréquence de la chimie d’un cours d’eau par spectrophotométrie UV-visible

    OpenAIRE

    Faucheux, Mikaël; Fovet, Ophélie

    2014-01-01

    La variabilité de la chimie d’un cours d’eau se manifeste sur des périodes courtes comme l’événement de crue (quelques heures), mais aussi plus longues, saisonnières, pluriannuelles et décennales. La mesure en continu de la qualité de l’eau est délicate. Les méthodes classiques et standardisées se basent sur des prélèvements d’eau dont les concentrations sont ensuite mesurées en laboratoire. Les contraintes liées au prélèvement, au stockage et aux coûts limitent donc fortement l’accès à des s...

  20. La fouille de graphes dans les bases de données réactionnelles au service de la synthèse en chimie organique

    OpenAIRE

    Pennerath, Frédéric; Napoli, Amedeo

    2006-01-01

    National audience; La synthèse en chimie organique consiste à concevoir de nouvelles molécules à partir de réactifs et de réactions. Les experts de la synthèse s'appuient sur de très grandes bases de données de réactions qu'ils consultent à travers des procédures d'interrogation standard. Un processus de découverte de nouvelles réactions leur permettrait de mettre au point de nouveaux procédés de synthèse. Cet article présente une modélisation des réactions par des graphes et introduit une mé...

  1. Industrial chemistry; Chimie industrielle

    Energy Technology Data Exchange (ETDEWEB)

    Perrin, R. [Universite Claude Bernard, UFR, 69 - Lyon (France); Scharff, J.P. [Universite Claude Bernard, 69 - Lyon (France)]|[Ecole Superieure de Chimie, Physique et Electronique CPE, 69 - Lyon (France)

    1997-12-31

    This book takes stock of the main aspects of the industrial chemistry. It presents all the current chemical aspects concerning the preparation of the main inorganic, metallurgical, organic products and polymers. Are included all the problems related to raw materials, energy, reactions optimization, chemical risk, environment and cleansing, patent rights. It is devoted to students, technical men and engineers. (O.M.) 239 refs.

  2. Physico-Chimie des Atomcules d'Hélium antiprotonique: Modélisation de Processus réactifs en présence d'Antimatière

    Science.gov (United States)

    Sauge, Sébastien

    2000-07-01

    Environ 3%des antiprotons (p) stoppés dans l'hélium survivent plusieurs microsecondes, contre quelques picosecondes dans tout autre matériau. Cette métastabilité inhabituelle résulte d'une capture sur des états liés de l'atome exotique pHe+, dénommé atomcule car il s'apparente à la fois à un atome de Rydberg quasi-circulaire quasi-classique de grand moment angulaire l n-1 37et à une molécule diatomique composée d'un noyau chargé négativement et caractérisée par une forte excitation rotationnelle J=l. En dehors de cette structure duale originale accessible par spectroscopie laser, la physico-chimie de leur interaction avec d'autres atomes ou molécules a fait l'objet d'études microscopiques. Alors que les atomcules résistent à des millions de collisions dans l'hélium pur, des contaminants moléculaires comme H2 les détruisent immédiatement, y compris à basse température. Dans le cadre Born-Oppenheimer, nous interprétons l'interaction moléculaire, calculée par des techniques de chimie quantique {ab initio}, en termes de chemins réactifs classiques, qui présentent des barrières d'activation compatibles avec celles mesurées dans He et H2.Nous montrons par une approche Monte Carlo de trajectoires classiques que la thermalisation détruit fortement les populations initiales, portant la fraction estimée des états de capture à 3%. Nous étudions aussi la recombinaison dissociative pHe+ + e+ e -dans une approche de trajectoires classiques pour les noyaux: nous prédisons la synthèse d'antihydrogène avec un rapport de branchement de 10%, ainsi qu'une nouvelle classe d'atomcules métastables ?={p}, e+, 2e-, qui pourrait être confirmée par spectroscopie. Ce travail illustre la transférabilité des concepts de chimie physique à l'étude de processus exotiques en présence d'antimatière, et apporte un éclairage nouveau sur la physico-chimie des radicaux interstellaires froids.

  3. The exhibition"La France au CERN" was inaugurated by Danièle Hulin, Directrice adjointe Secteur Physique, Chimie, Sciences pour l'Ingénieur (PCSI), Ministère délégué à l'Enseignement supérieur et à la recherche.

    CERN Multimedia

    Patrice Loïez

    2005-01-01

    The exhibition"La France au CERN" was inaugurated by Danièle Hulin, Directrice adjointe Secteur Physique, Chimie, Sciences pour l'Ingénieur (PCSI), Ministère délégué à l'Enseignement supérieur et à la recherche.

  4. Un siècle de chimie à l’Académie royale des sciences de sa création (1666 à l’arrivée de Lavoisier (1768

    Directory of Open Access Journals (Sweden)

    Bernard Joly

    2012-04-01

    Full Text Available Le laboratoire alchimique, qui passe volontiers pour le lieu privilégié de l’élaboration de la chimie ancienne, symbolisait à la fois le caractère privé, si ce n’est secret, de cette science et la nécessaire articulation de ses théories avec une pratique qui lui donnait son sens : il ne s’agissait pas seulement de trouver la pierre philosophale, mais aussi de fabriquer des médicaments et des substances chimiques répondant aux demandes sociales. Lieu privé, réservé à des disciples choisis, il ...

  5. Physique, chimie 1re S

    CERN Document Server

    2011-01-01

    • Des activités conçues pour correspondre aux pratiques des enseignants ou au temps d’enseignement attribué à une notion. Avec des « Découverte » courtes basées sur les savoirs que possède l’élève en début de chapitre et des « Documentaires » pour construire le cours avec leur « aide aux activités ». Ainsi que des TP pour pratiquer expérimentalement ou exploiter des données. • Un Cours structuré renvoyant aux activités, illustré, enrichi d’applications du cours avec renvois vers les exercices. Il se termine par l’essentiel. • De nombreux Exercices résolus avec des corrections détaillées et après le test de compétences, des exercices classés en entraînement et approfondissement et un exercice en langue anglaise. • Pour satisfaire la curiosité des élèves : Des pages « Culture et Sciences » en fin de cours. Et au long du manuel : L’histoire des sciences et L’histoire des arts. Un site pour les élèves www.micromega-hatier.com • Simulateurs en ...

  6. Green chemistry; La chimie verte

    Energy Technology Data Exchange (ETDEWEB)

    Colonna, P. [Institut National de la Recherche Agronomique, Dept. Caracterisation et Elaboration des Produits, 78 - Versailles (France)

    2006-07-01

    The depletion of world fossil fuel reserves and the involvement of greenhouse gases in the global warming has led to change the industrial and energy policies of most developed countries. The goal is now to reserve petroleum to the uses where it cannot be substituted, to implement renewable raw materials obtained from plants cultivation, and to consider the biodegradability of molecules and of manufactured objects by integrating the lifetime concept in their expected cycle of use. The green chemistry includes the design, development and elaboration of chemical products and processes with the aim of reducing or eliminating the use and generation of harmful compounds for the health and the environment, by adapting the present day operation modes of the chemical industry to the larger framework of the sustainable development. In addition to biofuels, this book reviews the applications of green chemistry in the different industrial processes in concern. Part 1 presents the diversity of the molecules coming from renewable carbon, in particular lignocellulose and the biotechnological processes. Part 2 is devoted to materials and treats of the overall available technological solutions. Part 3 focusses on functional molecules and chemical intermediates, in particular in sugar- and fats-chemistry. Part 4 treats of biofuels under the aspects of their production and use in today's technologies. The last part deals with the global approaches at the environmental and agricultural levels. (J.S.)

  7. Banking of environmental samples for short-term biochemical and chemical monitoring of organic contamination in coastal marine environments: the GICBEM experience (1986-1990). Groupe Interface Chimie Biologie des Ecosystèmes, Marins.

    Science.gov (United States)

    Garrigues, P; Narbonne, J F; Lafaurie, M; Ribera, D; Lemaire, P; Raoux, C; Michel, X; Salaun, J P; Monod, J L; Romeo, M

    1993-11-01

    The GICBEM (Groupe Interface Chimie Biologie des Ecosystèmes Marins) program consists of an evaluation of the ecosystem health status in the Mediterranean Sea mainly based on chemical and biochemical approaches. Specific chemical contaminants (polycyclic aromatic hydrocarbons (PAH), polychlorobiphenyls (PCB), heavy metals) in waters, sediments, and related biotransformation indicators in target organisms (mussels, fish) have been selected for a complete survey of the coastal waters. In order to provide an appropriate sampling program for standardization for each sampling cruise, various aspects have been studied: (a) parameters for the choice of the sample sites; (b) ways of collection the samples (waters, sediments, marine organisms); and (c) preparation of the samples for a short term storage on board ship and for further analyses in the ground laboratory. Methods of preparation and storage of the samples are described and could be used to initiate an environmental banking program including both possible retrospective analyses of chemical pollutants and biochemical indicators. Moreover, the correlation between chemicals (PAH) and biochemical (mixed function oxygenase activities) parameters has been studied and this demonstrates the capability of the enzyme activities as reliable pollution biomarkers.

  8. Zur Geologie des nordöstlichen Indischen Archipels

    NARCIS (Netherlands)

    Bücking, H.

    1902-01-01

    Die Insel Siauw macht, wie ich bereits früher berichtet habe ¹), den Eindruck, als ob sie durchaus vulkanisch sei. Zwar hat FRENZEL ²) ausser grobkörnigem, olivinhaltigem und dichtem, olivinfreiem Augitandesit auch noch ein Gneissgerölle von hier erwähnt; indessen dürfte bezüglich dieses Stückes ent

  9. Qu’est-ce qui fait courir les filles vers la classe préparatoire scientifique Biologie, Chimie, Physique et Sciences de la Terre (BCPST ? What attracts girls in science classes: Biology, Chemistry, Physics and Earth Studies?

    Directory of Open Access Journals (Sweden)

    Christine Fontanini

    2011-10-01

    Full Text Available Cet article a pour objectif de comprendre pourquoi les filles sont nombreuses (70 % à s’engager vers la classe préparatoire scientifique Biologie, Chimie, Physique, Sciences de la Terre (BCPST alors qu’elles restent minoritaires dans les autres préparations scientifiques (Pons, 2007. Comment se sont construits pour ces étudiants et étudiantes, leur projet et leur parcours scolaire vers cette classe préparatoire « bio-véto » ? Quelles sont leurs motivations pour cette filière menant aux professions de vétérinaire et d’ingénieur agronome ? Quelles sont les écoles les plus convoitées ? Quels sont leurs projets professionnels ? Sont-ils différents entre les filles et les garçons ? Pour tenter de répondre à ces questions, nous avons mené une recherche par questionnaire, courant septembre 2008, auprès de 163 élèves de 4 classes préparatoires BCPST de première année (113 filles et 50 garçons des 3 lycées toulousains proposant cette filière dans l’académie. Les filles sont largement majoritaires en classes préparatoires BCPST car leurs débouchés apparaissent comme plus attractifs pour les filles, notamment les écoles vétérinaires.This paper examines why girls are more numerous (70% in the scientific preparatory classes BCPST (Biology, Chemistry, Physics and Earth whereas they are a minority in the other scientific preparatory classes (Pons, 2007. How have female and male built their occupational preferences and their school choices for this preparatory class “biology – vet science”? What are their motivations for this pathway which prepares for veterinarian and agricultural engineer? What are the most desired schools? What are their professional plans? Are they different between girls and boys? In order to answer these questions, a questionnaire survey was conducted in September 2008, on a sample of 163 pupils (113 girls and 50 boys from 4 first year preparatory classes BCPST in 3 Toulousian high

  10. In de entourage van de Farao. Kunst en archeologie in de Thebaanse necropool

    OpenAIRE

    Bavay, Laurent; Laboury, Dimitri

    2012-01-01

    The Theban necropolis, opposite the modern city of Luxor, has been Egypt’s most important burial place during the New Kingdom (ca. 1550-1050 BC). Since 1999, the Université libre de Bruxelles undertakes a long-term, interdisciplinary study of a large area in the southern part of the Sheikh Abd el-Qurna hill, densely occupied during the mid-18th dynasty. Initially focusing on two monuments dating to the reign of Amenhotep II, the tombs of the Prince of the City Sennefer (TT 96) and the vizier ...

  11. Archeologie sous-marine de l'ancienne Dwarka dans l'Okhamandal

    Digital Repository Service at National Institute of Oceanography (India)

    Gaur, A.S.

    was another very important port during historical and medieval periods. One of the major attraction for the ancient people was the richness of marine resources around the Okhamandal region particularly chank shell (Turbunella pyrum) which has been used...

  12. Sondes intégrées résonantes de lumière : Micro-résonateurs sur polymères couplés aux technologies et procédés issus de la chimie, des plasmas, de la micro-fluidique et de la biophysique

    OpenAIRE

    Bêche, Bruno; Huby, Nolwenn; Moréac, Alain; Vié, Véronique; Panizza, Pascal; Lhermite, Hervé; Solal, Francine

    2015-01-01

    National audience; Au cours de cette allocution, quelques voies de recherche et développement en photonique intégrée à base de matériaux organiques seront développées. Plusieurs approches hybrides qui sont issues de domaines transverses de la physique et de la chimie pour la réalisation de Micro-Résonateurs (MRs) 2D, 2.5D et 3D sur polymères seront présentées. De telles voies parallèles soulignent l'intérêt de développer des technologies et procédés hybrides, comme les traitements plasmas, la...

  13. Nitrous Oxide from Combustion and Industry: Chemistry, Emissions and Control Protoxyde d'azote provenant de la combustion et de l'industrie : chimie, émissions et techniques de réduction

    Directory of Open Access Journals (Sweden)

    De Soete G.

    2006-11-01

    'industrie chimique, d'autre part il s'interroge sur les technologies possibles de destruction de N2O dans les cas où sa teneur dans les fumées ou autres effluves industriels pose des problèmes. Comme les émissions, aussi bien que les moyens de les abattre, sont fortement tributaires des mécanismes chimiques responsables de la production et de la destruction du N2O, une introduction substantielle sur la cinétique homogène et hétérogène de sa formation/réduction, telle qu'elle apparaît dans un contexte de combustion, est fournie, permettant au lecteur de comprendre le pourquoi de ces émissions et le comment des technologies d'abattement suggérées. Dans une première section de l'introduction, on rappelle brièvement la chimie du N2O en phase gazeuse et ses relations avec la chimie du monoxyde d'azote NO (fig. 1 ; l'effet de la température sur la production nette de N2O est accentué, puisqu'elle expliquera en grande partie les émissions relativement élevées de la combustion à basse température, telle qu'elle est mise en oeuvre dans les lits fluidisés (fig. 2. On mentionne pour finir les réactions du système rédox SO2/NO (fig. 3, responsable de la formation artificiellede N2O dans les échantillons de fumées stockés. La deuxième section de l'introduction traite de la chimie hétérogène du protoxyde d'azote, dont la compréhension est actuellement encore relativement fragmentaire. Parmi les mécanismes hétérogènes non catalytiques, figurent principalement : la réduction de N2O sur le carbone constitutif du charbon et du coke, la formation de N2O à partir de l'azote constitutif de ces derniers et la production de N2O par des réactions entre carbone, NO et sulfates. Les deux premiers mécanismes sont traités en parallèle avec ceux, similaires, qui opèrent sur le NO, auxquels ils sont intimement liés (voir tableau 1 et réactions S1 à S8 dans le texte. La réduction de N20 sur carbone constitutif ne produit que peu de N2O, au moins en absence d

  14. Chemistry of actinides; Chimie des actinides

    Energy Technology Data Exchange (ETDEWEB)

    Vitorge, P. [CEA/Saclay, Dept. d' Entreposage et de Stockage des Dechets (DESD), 91 - Gif-sur-Yvette (France)

    1999-07-01

    This article gives the basic data of the actinides chemistry, describes then qualitatively the main parts of the fuel cycle and concludes with quantitative data. The theoretical recalls give qualitative notions to explain the chemical reactivity of actinides and to understand thus the values of the thermodynamic data which allow quantitative anticipations at equilibrium. The Thermodynamic Data Base (TDB) of the NEA-OECD and the CEA in France have recently estimated some of them in using and developing methodologies whose some are presented here. Some current problems of actinides chemistry are described: analysis of the possibilities to (1)improve the reprocessing of long-lived actinides (2)anticipate their behaviour in the environment in order to compare the impact of the different options of the wastes management. The Pourbaix diagrams summarize the chemistry in solution; the author has added information on the solubility, the influence of the ionic strength and of the complexes formation in bicarbonate/carbonate (HCO{sub 3}{sup -}/CO{sub 3}{sup 2-}) media. The discussion on the choice of the equilibrium constants allows to point out the particular points, the dubiousness and the data which have to be proved. (O.M.)

  15. Chemistry and propulsion; Chimie et propulsions

    Energy Technology Data Exchange (ETDEWEB)

    Potier, P. [Maison de la Chimie, 75 - Paris (France); Davenas, A. [societe Nationale des Poudres et des Explosifs - SNPE (France); Berman, M. [Air Force Office of Scientific Research, Arlington, VA (United States)] [and others

    2002-07-01

    During the colloquium on chemistry and propulsion, held in march 2002, ten papers have been presented. The proceedings are brought in this document: ramjet, scram-jet and Pulse Detonation Engine; researches and applications on energetic materials and propulsion; advances in poly-nitrogen chemistry; evolution of space propulsion; environmental and technological stakes of aeronautic propulsion; ramjet engines and pulse detonation engines, automobiles thermal engines for 2015, high temperature fuel cells for the propulsion domain, the hydrogen and the fuel cells in the future transports. (A.L.B.)

  16. A Physics and Tabulated Chemistry Based Compression Ignition Combustion Model: from Chemistry Limited to Mixing Limited Combustion Modes Un modèle de combustion à allumage par compression basé sur la physique et la chimie tabulée : des modes de combustion contrôlés par la chimie jusqu’aux modes contrôlés par le mélange

    Directory of Open Access Journals (Sweden)

    Bordet N.

    2011-11-01

    experimental measurements carried out on a 2 liter Renault Diesel engine and good agreements are found. Ce papier présente une nouvelle approche 0D phénoménologique pour prédire le déroulement de la combustion dans les moteurs Diesel à injection directe pour toutes les conditions d’utilisation usuelles. Le but de ce travail est de développer une approche physique en vue d’améliorer la prédiction de la pression cylindre et du dégagement d’énergie, avec un nombre minimum d’essais nécessaires à la calibration. Les contributions principales de cette étude sont la modélisation de la phase de pré-mélange de la combustion et une extension du modèle pour les stratégies d’injections multiples. Dans ce modèle, le taux de dégagement d’énergie dû à la combustion pour la phase pré-mélangée est relié à un taux de réaction moyen du carburant. Ce taux de réaction moyen de carburant est évalué à l’aide d’une approche basée sur un taux de réaction local de carburant tabulé et la détermination d’une fonction de densité de probabilité (PDF de la fraction de mélange (Z. Cette PDF permet de prendre en compte la distribution de richesse existante dans la zone pré-mélangée. L’allure de cette PDF présumée est une β-fonction standardisée. Les fluctuations de la fraction de mélange sont décrites avec une équation de transport pour la variance de Z. La définition standard de la fraction de mélange, établie dans le cas de flammes de diffusion, est ici adaptée à une combustion pré-mélangée de type Diesel pour décrire l’inhomogénéité de la richesse dans le volume de contrôle. La chimie détaillée est décrite au travers de la tabulation du taux de réaction relatif à la flamme principale et du délai d’auto-inflammation relatif à la flamme froide, ces tabulations sont fonction de la variable d’avancement c, du taux de gaz brûlé ainsi que des grandeurs thermodynamiques telles que la température et la pression. Le

  17. Aplikace nedestruktivních archeologických metod na Katedře archeologie v Plzni

    Directory of Open Access Journals (Sweden)

    Petr Baierl

    2012-08-01

    Full Text Available Non-destructive archaeological approaches and methods have become an inseparable part of archaeological monument survey. They are also frequently used at the Department of Archaeology in Plzen. Here, over the past years, they have been applied in a number of cases. These include non-destructive documentation works on barrow burial and hill top sites, or the Middle Age and Modern settlements in forested areas Other significant activities have been carried out by means of geophysical surveys or aerial photography and remote sensing of Earth.

  18. De visserskaai te Oostende (prov. West-Vlaanderen): archeologie van een in de 17de eeuw zwaar geteisterde stad

    OpenAIRE

    2003-01-01

    The Institute for the Archaeological Heritage of the Flemish Community (IAP) has, in close collaboration with the town of Ostend, carried out archaeological excavations during the construction works of the car park below the Visserskaai at Ostend from September 1998 till February 1999. This archaeological work mainly produced information on the eastern ramparts of Ostend and their evolution from the 16th century onwards together with information on the material culture of the inhabitants of O...

  19. Underwater search of ancient Dwarka in Okhamandal (Archeologie sous-marine de l'ancienne Dwarka dans l'Okhamandal)

    Digital Repository Service at National Institute of Oceanography (India)

    Gaur, A.S.

    was another very important port during historical and medieval periods. One of the major attraction for the ancient people was the richness of marine resources around the Okhamandal region particularly chank shell (Turbunella pyrum) which has been used...

  20. Geologie study off gravels of the Agua Fria River, Phoenix, AZ

    Science.gov (United States)

    Langer, W.H.; Dewitt, E.; Adams, D.T.; O'Briens, T.

    2010-01-01

    The annual consumption of sand and gravel aggregate in 2006 in the Phoenix, AZ metropolitan area was about 76 Mt (84 million st) (USGS, 2009), or about 18 t (20 st) per capita. Quaternary alluvial deposits in the modern stream channel of the Agua Fria River west of Phoenix are mined and processed to provide some of this aggregate to the greater Phoenix area. The Agua Fria drainage basin (Fig. 1) is characterized by rugged mountains with high elevations and steep stream gradients in the north, and by broad alluvial filled basins separated by elongated faultblock mountain ranges in the south. The Agua Fria River, the basin’s main drainage, flows south from Prescott, AZ and west of Phoenix to the Gila River. The Waddel Dam impounds Lake Pleasant and greatly limits the flow of the Agua Fria River south of the lake. The southern portion of the watershed, south of Lake Pleasant, opens out into a broad valley where the river flows through urban and agricultural lands to its confluence with the Gila River, a tributary of the Colorado River.

  1. Geologie, Globalisierung und Expertentum. Eine Wissensgeschichte des Eisenerzes in Brasilien (working title)

    DEFF Research Database (Denmark)

    Fischer, Georg

    2017-01-01

    We treat, as an illustrative example of gravitational time dilation in relativity, the observation that the centre of the Earth is younger than the surface by an appreciable amount. Richard Feynman first made this insightful point and presented an estimate of the size of the effect in a talk...

  2. De geologie van den Cimone di Margno en den Monte di Muggio

    NARCIS (Netherlands)

    Buning, W.L.

    1931-01-01

    Le terrain étudié (fig. 1) est formé de roches métamorphiques pour plus de la moitié; le reste est formé de sédiments variant du Permien au Trias Inférieur, et de roches appartenant à la culmination éruptivocristalline du Cimone di Margno. Le relief du paysage présente en général des pentes douces.

  3. De ontwikkelingsgeschiedenis van Rein van Bemmelens (1904-1983 undatietheorie: veertig jaar Nederlandse geologie

    Directory of Open Access Journals (Sweden)

    Willemjan Barzilay

    2009-03-01

    Full Text Available The development of Rein van Bemmelens (1904-1983 undation theory: Forty years of Dutch geology The Dutch geologist Rein van Bemmelen was the greatest opponent of plate tectonics in the Netherlands. He lived and worked during an important period in the history of earth sciences. He had studied geology when Wegeners theory was introduced and enthusiastically received in the Netherlands and he worked as a geologists during the period in which, after Wegeners theory was rejected in the Netherlands, several Dutch geologists came with their own theories to explain the origin of continents and oceans and in which plate tectonics was introduced in the Netherlands. He had proposed his own theory, the undation theory, at the beginning of the 1930s and kept on developing it during the following years. He continued to do so until his death in 1983. The history of the undation theory thus sheds light on the history of geology in the Netherlands. I will trace the history of geology in the Netherlands using Rein van Bemmelen and his undation theory as a lense.

  4. Geology of uranium vein-deposits in France; Geologie des gites uraniferes et filoniens en France

    Energy Technology Data Exchange (ETDEWEB)

    Sarcia, J.A.; Carrat, J.; Poughon, A.; Sanselme, H. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    This paper gives an outline of the characteristics of the main uranium vein deposits in France; it underlines the structural, petrographic and metallogenic similarities of these deposits. (author) [French] La note presente est un expose des caracteres generaux des principaux gites uraniferes filoniens de France; elle insiste sur les similitudes structurales, petrographiques et metallogeniques de ces gisements. (auteur)

  5. De Geologie van het Val Brembo di Foppolo en de Valle di Carisole

    NARCIS (Netherlands)

    Wennekers, J.H.L.

    1928-01-01

    Le terrain exploré fait partie du prolongement vers l’est de la zone des Alpes bergamasques que Cosijn et Jong ont commencé à mettre en carte en 1926 (fig. 1). Il comprend des parties du cristallin situé au nord de la „ligne orobique”, du paquet d’écaillés (série porphyrique, série Collio,

  6. De Geologie van het Val Brembo di Foppolo en de Valle di Carisole

    NARCIS (Netherlands)

    Wennekers, J.H.L.

    1928-01-01

    Le terrain exploré fait partie du prolongement vers l’est de la zone des Alpes bergamasques que Cosijn et Jong ont commencé à mettre en carte en 1926 (fig. 1). Il comprend des parties du cristallin situé au nord de la „ligne orobique”, du paquet d’écaillés (série porphyrique, série Collio, Verrucano

  7. Some unusual gemstones in the collection of the Rijksmuseum van Geologie en Mineralogie of Leiden

    NARCIS (Netherlands)

    Zwaan, P.C.

    1955-01-01

    Our Museum can take pride in a very valuable gem collection for, besides the numerous specimens which were gathered by King William I of the Netherlands a great many of the more unusual stones are to be found in it. Especially since World War II the Museum has acquired many interesting and important

  8. De geologie van den Cimone di Margno en den Monte di Muggio

    NARCIS (Netherlands)

    Buning, W.L.

    1931-01-01

    Le terrain étudié (fig. 1) est formé de roches métamorphiques pour plus de la moitié; le reste est formé de sédiments variant du Permien au Trias Inférieur, et de roches appartenant à la culmination éruptivocristalline du Cimone di Margno. Le relief du paysage présente en général des pentes douces.

  9. 燜ounding of Modern Doctrine of Chemical Element-For the Bicentenary of Lavoisier'sraite lementaire de Chimie%近代化学元素学说的奠立——纪念拉瓦锡《化学纲要》出版二百周年

    Institute of Scientific and Technical Information of China (English)

    曾敬民; 赵匡华

    1989-01-01

    @@法国杰出化学家安东尼·罗朗·拉瓦锡(AntoineLaurent Lavoisier,1743一1794)的划时代名著《化学纲要》(TraiteElementaire de Chimie)于1789年出版,到今年整整二百周年。这部辉煌的著作为使化学确立为一门真正的独立学科奠定了基础,它对化学的贡献完全可以和牛顿的《自然哲学的数学原理》对物理学的贡献媲美。它的问世标志着化学新纪元的开端,从此化学进入了近代发展时期。 《化学纲要》不仅是拉瓦锡全部化学研究成果的结晶,而且是对十八世纪末发生的化学革命的总结。限于篇幅,本文着重对拉瓦锡在《化学纲要》中所阐述的近代化学元素学说作一新的历史评价,而对这部巨著的其他方面仅作简要的评述。一、波义耳并没有提出科学的元素概念不少化学史家曾误认为,拉瓦锡的元素定义本质上和波义耳的定义一样[1]。其实,这种观点是由于对“波义耳元素定义”的错误理解造成的。早在1930年,T.L.Davis就认为:“《怀疑派化学家》一书并非旨在提出新的元素观念,书中所述的元素观念也不是始于波义耳。”[2]五十年代初,Marie Boas又指出,“现在人们在讨论波义耳的元素定义时常常忽视了这样一个事实:正是这个表面上正确的定义导致波义耳怀疑存在任何元素。”[3

  10. Physico-chimie des fruits du safoutier (Dacryodes edulis camerounais

    Directory of Open Access Journals (Sweden)

    Kapseu, C.

    1999-01-01

    Full Text Available Physico-Chemistry of Cameroonian Safou Tree Fruits Dacryodes edulis. Safou tree (Dacryodes edulis is a part of the agrarian landscapes of tropical countries. Although it is known as a multiple purposes tree, it is still underexploited. This is due to the lack of scientific knowledge and data. The aim of this work is to determine the physicochemical properties of safou tree fruits. These fruits, called safou, are consumed less than two days after harvest. The morphologic character vary according to the area and the types. In Cameroon, oil content varies from 47.4 to 61.1 % according to the agro-climatic areas : soudano saharian, high lands and continental area. The fatty acid composition of the oil, determined by gas chromatographie on capillary column, is rich in palmatic acid (35.4-46.0 % of total fatty acids and in oleic acid (27.2-39.8 %. Analysis of triglycerides shows that 4 triglycerides only represent more than 70 % of total triglycerides : palmitodiolein (19.2-27 %, dipalmito-olein (16.8-26.1 %, palmito-oleo-linolein (14.7-18.5 %, dipalmito-linolein (10.5-17.6 %.

  11. Fascinating morphologies of lead tungstate nanostructures by chimie douce approach

    Energy Technology Data Exchange (ETDEWEB)

    George, Thresiamma; Joseph, Sunny; Sunny, Anu Tresa; Mathew, Suresh [Mahatma Gandhi University, School of Chemical Sciences (India)], E-mail: smathew_mgu@yahoo.com

    2008-04-15

    Lead tungstate occurs in nature as tetragonal stolzite of scheelite (CaWO{sub 4}) type and monoclinic raspite. In this work, we report, the typical growth of snowflake-like tetragonal stolzite and bamboo-leaf-like monoclinic raspite nanocrystals of PbWO{sub 4} via a simple aqueous precipitation method and a polyol (polyethylene glycol-200) mediated precipitation method at room temperature (27 deg. C). The synthesised PbWO{sub 4} nanocrystals were characterised by XRD, SEM, EDAX and TGA-DTA. The UV-Vis absorption and photoluminescence studies of PbWO{sub 4} nanocrystals in the two morphologies were performed. The nuclei of PbWO{sub 4} nanocrystals in aqueous medium self-assemble in a tetragonal manner to form the snowflake-like crystals. In polyol medium, PbWO{sub 4} nuclei preferentially grow by oriented attachment process to form the bamboo-leaf-like morphology. The specific morphology of the regularly assembled PbWO{sub 4} nanocrystals in the two phases finds applications in nanoelectronics and photonics. Compared to other well-known scintillators, PbWO{sub 4} is most attractive for high-energy physics applications, because of its high density, short decay time and high irradiation damage resistance.

  12. Chemistry, sun, energy and environment; Chimie, soleil, energie et environnement

    Energy Technology Data Exchange (ETDEWEB)

    Bouchy, M. [Ecole Nationale Superieure des Industries Chimiques (ENSIC), 54 - Villers-les-Nancy (France); Enea, O. [Poitiers Univ., 86 (France); Flamant, G. [IMP-Odeillo-CNRS (France)] (and others)

    2000-07-01

    This document provides the 35 papers presented at the 'Chemistry, Sun, Energy and Environment' meeting, held February 3-4, 2000 in Saint-Avold, France. The main studied topic was the use of solar radiation for water treatment, volatile organic compounds decomposition and in some thermochemical processes. These research subjects are tackled in a fundamental and practical point of view. (O.M.)

  13. Iminoéthers-1 3 cycliques : chimie et applications dans le domaine des additifs pétroliers et des matériaux organiques Cyclic 1,3-Iminoethers: Chemistry and Applications in the Field of Petroleum Additives and Organic Materials

    Directory of Open Access Journals (Sweden)

    Le Perchec P.

    2006-11-01

    Full Text Available Cet article est consacré aux iminoéthers-1,3 cycliques les plus courants : les oxazines-1,3 et oxazolines-1,3. La première partie rappelle les synthèses de ces composés et quelques aspects récents de leur chimie : réactions d'hydrolyse, réactions de déprotonation avec ouverture de cycle, réactions des organométalliques, réactions d'addition des nucléophiles en positions 2 et 5, des sels d'iminoéthers correspondants, propriétés complexantes vis-à-vis des métaux, réactions d'aminolyse et formation de structures tensioactives, enfin polymérisations et copolymérisations cationiques. La seconde partie est consacrée à l'étude des travaux qui traitent des applications. En ce qui concerne le domaine des additifs pétroliers, on s'intéresse à la stabilité du cycle oxazoline et à son caractère polaire. Les dérivés tensioactifs dérivés d'oxazoline portant des chaînes hydrocarbonées ont été revendiqués comme additifs dispersants et multifonctionnels pour les carburants et les lubrifiants. De nombreuses formulations (dispersants, antioxydants antirouilles, antiusures, extrême pressions, réducteurs de frictions. . . ont été proposées. Certains dérivés d'hydroxyméthyl oxazolines présentent des propriétés lubrifiantes et d'autres ont un intérêt dans les formulations de boues de forage. En ce qui concerne le domaine des matériaux, on s'intéresse à la réactivité du cycle oxazoline pour réaliser soit des extensions de chaînes des thermoplastiques, soit des réticulations pour des applications de peintures et revêtements. Les homopolymères d'oxazoline qui ont un caractère polaire très marqué peuvent trouver des applications comme promoteur d'adhésion, ou tensioactifs pour les polymérisations en émulsion. Enfin, l'utilisation d'oxazolines stables a été revendiquée dans des formulations de vernis d'émaillage. This article deals with the most common cyclic 1,3-iminoethers, i. e. 1,3-oxazines and 1

  14. Kwartaire Bovidae van Nederland. De schedels en hoornpitten, welke zich bevinden in het Rijksmuseum van Geologie te Leiden

    NARCIS (Netherlands)

    Vlerk, van der I.M.

    1942-01-01

    The plates I—XI contain illustrations of all the skulls and horn-cores of Bovidae from the Quaternary of the Netherlands, brought together in the National Museum of Geology at Leyden, Holland. They were all photographed with the occiputs vertical or what is thought to be vertical. They are described

  15. Combustion chemistry and formation of pollutants; Chimie de la combustion et formation des polluants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This book of proceedings reports on 7 papers on combustion chemistry and formation of pollutants presented during the workshop organized by the `Combustion and Flames` section of the French society of thermal engineers. The chemistry of combustion is analyzed in various situations such as: turbojet engines, spark ignition engines, industrial burners, gas turbines etc... Numerical simulation is used to understand the physico-chemical processes involved in combustion, to describe the kinetics of oxidation, combustion and flame propagation, and to predict the formation of pollutants. (J.S.)

  16. Émile Meyerson, de la chimie à la philosophie des sciences

    Directory of Open Access Journals (Sweden)

    Eva Telkes-Klein

    2008-01-01

    Full Text Available Cet article suit le chemin, atypique, qu’emprunte Émile Meyerson pour passer de la profession de chimiste à la pratique de la philosophie et de la philosophie des sciences. Son parcours est atypique puisque Meyerson ne bénéficie d’aucune position académique qui lui permette de vivre de sa science. Cependant ce chemin, qui le fait changer de statut, le mène à une position de figure importante dans le champ de la tradition française de la philosophie des sciences. Ainsi, Dominique Parodi donne ...

  17. Modèles en chimie théorique, développements et applications

    OpenAIRE

    2015-01-01

    Trois thèmes de recherche sont présentés dans ce travail.Les pseudo potentiels moléculaires développés dans le cadre de ce travail sont des potentiels développé&s pour des atomes hybridés. Le cas de l'atome de carbone sp2 est développé, que ce soit pour l'atome seul ou pour l'atome en interaction avec d’autres atomes portant ou non des pseudo potentiels. Grâce à ce travail, il est possible de reproduire avec précision la spectroscopie de polyènes, d'hydrocarbures polycycliques aromatiques et ...

  18. Industrial chemistry. Tome 2, solved exercises; Chimie industrielle. Tome 2, problemes resolus

    Energy Technology Data Exchange (ETDEWEB)

    Lefrancois, B. [Conservatoire National des Arts et Metiers (CNAM), 75 - Paris (France)

    1996-07-01

    This book is a complement to the first tome and proposes 20 exercises relative to industrial chemical processes with their solutions. Each exercise refers to an existing process with numerical data based on real operation data or process schemes: matter statement, energy statement and recovery, separation units, safety.. The following processes are considered: sulfur combustion, fabrication of oleum, chlorine, sulfur trioxide, producer gas, formaldehyde, hydrocyanic acid, ethanol, acetic anhydride, acetone, urea, butadiene 1-3, isopropanol, vinyl acetate, dealkylation of toluene, dehydrogenation of ethylbenzene, fabrication of styrene, combustion of diesel fuels, combustion of a gas mixture, fabrication of methyl chloride, refrigeration cycle, methane liquefaction. (J.S.)

  19. Industrial chemistry. Tome 1, course and solved exercises; Chimie industrielle. Tome 1, cours et problemes resolus

    Energy Technology Data Exchange (ETDEWEB)

    Lefrancois, B. [Conservatoire National des Arts et Metiers (CNAM), 75 - Paris (France)

    1999-07-01

    This manual about industrial chemistry brings together the fundamental principles of thermodynamics and of chemical engineering in order to describe some processes of industrial chemistry. It integrates also the industrial constraints, such as the optimization, the automation, the health aspects, the industrial property etc.. It is shared into two parts, a theoretical part, followed by a series of exercises with their solution. The theoretical part deals successively with: the thermodynamics: energy statements, chemical equilibrium, open systems and thermodynamical analysis of processes; the properties of gas and liquids and the separation processes. The exercises part comprises: hydrogen production from partial oxidation of methane, fabrication of sulfur dioxide, of aniline, of ethylene oxide, preparation of a synthetic gas, synthesis of ammonia (thermodynamic analysis, absorption, desorption), synthesis of methanol, fabrication of methyl-amines (refrigeration cycles, enthalpy diagram) cumene, acetic anhydride, conversion of carbon oxide, preparation of ethyl acetate and ethyl chloride. (J.S.)

  20. Radiation chemistry - From basics to applications in material and life sciences; Chimie sous rayonnement

    Energy Technology Data Exchange (ETDEWEB)

    Belloni, J. [Paris-11 Univ., Dir. CNRS, Lab. de Chimie Physique, ELYSE, 91 - Orsay (France); Mostafavi, M. [Paris-11, Lab. de Chimie Physique (LCP), Centre ELYSE-CLIO, 91 - Orsay (France); Douki, T. [CEA Grenoble, Lab. Lesions des Acides Nucleiques, 38 (France); Spotheim-Maurizot, M. [Institut National de la Sante et de la Recherche Medicale (INSERM), 75 - Paris (France); Centre de Biophysique Moleculaire, 45 - Orleans (France)

    2008-02-15

    Radiation chemistry concerns various domains, for primary phenomena induced by energy absorption, to very numerous chemical mechanisms it allows to elucidate and to the synthesis applications of performing materials, or to very efficient physico-chemical treatments it can cause. The understanding of biochemical mechanisms, healthy or pathogenic, is a crucial challenge at which the radiation chemistry gives a decisive contribution for health, and which is essential in particular for using at best the chemo-radiotherapy tool in neoplasms treatment. (O.M.)

  1. Installation for analytic chemistry under irradiation; Installation de chimie analytique sous rayonnement

    Energy Technology Data Exchange (ETDEWEB)

    Fradin, J.; Azoeuf, P.; Guillon, A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1966-07-01

    An installation has been set up for carrying out manipulations and chemical analyses on radioactive products. It is completely remote-controlled and is of linear shape, 15 metres long; it is made up of three zones: - an active zone containing the apparatus, - a rear zone giving access to the active zone, - a forward zone independent of the two others and completely protected from which the remote-control of the apparatus is effected. The whole assembly has been designed so that each apparatus corresponding to an analytical technique is set up in a sealed enclosure. The sealed enclosures are interconnected by a conveyor. After three years operation, a critical review is now made of the installation. (authors) [French] L'installation a ete realisee pour effectuer des manipulations et des analyses chimiques sur des produits radioactifs. Elle est totalement telecommandee et se presente sous une forme lineaire de 15 metres de longueur et comporte trois zones: - une zone active d'appareillage, - une zone arriere d'intervention, - une zone avant independante des deux premieres et totalement protegee, ou s'operent les telecommandes de l'appareillage. L'ensemble a ete concu de facon a ce que chaque appareillage correspondant a une technique d'analyse soit implante dans une enceinte etanche. Les enceintes etanches sont reliees entre elles par un convoyeur. Apres trois annees de fonctionnement nous faisons le bilan et les critiques de l'installation. (auteurs)

  2. Study of catalytic phenomena in radiation chemistry; Etude des phenomenes catalytiques en chimie des radiations

    Energy Technology Data Exchange (ETDEWEB)

    Dran, J.C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-01-01

    Two phenomena have been studied: the action of {gamma} rays from radio-cobalt on the adsorption and catalytic properties of ZnO and NiO in. relationship with the heterogeneous oxidation of CO, and the homogeneous catalysis by OsO{sub 4} of the oxidation of various aqueous phase solutes by the same radiation. The prior irradiation of ZnO and of NiO does not modify their catalytic activity but generally increases the adsorption energy of -the gases CO and O{sub 2}. The influence of the radiations appears to be connected with the presence of traces of water on ZnO and of an excess of oxygen on NiO. Osmium tetroxide which is not degraded by irradiation in acid solution, accelerates the radiolytic oxidation of certain compounds (Te{sup IV}, Pt{sup 11}, As{sup 111}) in the presence of oxygen, as a result of its sensitizing effect on the oxidation by H{sub 2}O{sub 2}. In the case of phosphites on the other hand, OsO{sub 4} has a protecting action under certain conditions of acidity and may suppress entirely the chain reaction which characterizes the oxidation of this solute by{gamma} rays. A general mechanism is proposed for these phenomena. The rate constant for the OsO{sub 4} + HO{sub 2} reaction is calculated to be 5.7 x 10{sup 5} l.mol{sup -1}. sec{sup -1}. (author) [French] Deux phenomenes ont ete etudies: l'action des rayons {gamma} du radio-cobalt sur les proprietes adsorptives et catalytiques de ZnO et NiO en relation avec l'oxydation heterogene de CO et la catalyse homogene par OsO{sub 4} de l'oxydation de divers solutes en phase aqueuse par ce meme rayonnement. L'irradiation prealable de ZnO et de NiO n'a pas modifie leur activite catalytique, mais a generalement accru l'energie d'adsorption des gaz CO et O{sub 2}. L'influence des radiations semble liee a la presence de traces d'eau sur ZnO et d'un exces d'oxygene sur NiO. Le tetroxyde d'osmium qui n'est pas altere par le rayonnement en solution acide, accelere l'oxydation radiolytique de certains composes. (Te{sup IV}, Pt{sup 11} et As{sup 111}) en la presence d'oxygene, par suite de son effet sensibilisateur sur l'oxydation par H{sub 2}O{sub 2}. Dans le cas des phosphites, par contre, OsO{sub 4} exerce une action protectrice dans certaines conditions d'acidite, en conduisant eventuellement a la suppression, de la reaction en chaine qui caracterisa l'oxydation de ce solute par les rayons {gamma}. Un mecanisme general de ces phenomenes est propose. La constante de vitesse de la reaction OsO{sub 4} + HO{sub 2} est evalue a 5,7.10{sup 5} I.mol{sup -1} s{sup -1}. (auteur)

  3. Medical imaging and chemistry; La chimie au service de l'imagerie medicale

    Energy Technology Data Exchange (ETDEWEB)

    Meunier, J.P. [Schering France, Imagerie Medicale, 59 - Lys Les Lannoy (France); Schorsch, G. [Actualite Chimique, 75 - Paris (France); Zimmermann, R. [Cis Bio International-Schering, Dir. Recherche et Developpement, 91 - Gif sur Yvette (France)

    2003-12-01

    Diagnostic imaging frequently requires the use of agents that do not show an obvious role to patients. Nevertheless, these products fall definitely in the drug category and therefore are bound to the same development constraints, although no therapeutic effects are expected. This article attempts to explain the physical background of the most common imaging technologies as well as the mechanisms of action of the administered products. With these substances it is now possible to get morphological information with techniques based on X-rays, magnetic resonance or ultrasound, but also to obtain information on the functions of organs or cells by using radiolabeled molecules. Progresses, perspectives and limits of these technologies are described through several concrete examples. This overview demonstrates also that imaging participates strongly to the development of medicine. Diagnostics benefit simultaneously from technology improvements and new pharmaceuticals. (author)

  4. Chemistry 30: Grade 12 Diploma Examination = Chimie 30: Examen en vue du diplome 12 annee.

    Science.gov (United States)

    Alberta Dept. of Education, Edmonton. Student Evaluation Branch.

    This document, in both French and English versions, is the Chemistry 30 Grade 12 Diploma Examination from Alberta Education. It is a 2.5 hour closed-book examination consisting of 44 multiple-choice and 12 numerical-response questions of equal value that are worth 70% of the examination, and 2 written-response questions of equal value worth 30% of…

  5. Laboratoire de Chimie Bactérienne C.N.R.S., Marsielle, France.

    Science.gov (United States)

    Chippaux, M; Giudici, D; Abou-Jaoudé, A; Casse, F; Pascal, M C

    1978-04-06

    Mutants of E. coli, completely devoid of nitrite reductase activity with glucose or formate as donor were studied. Biochemical analysis indicates that they are simultaneously affected in nitrate reductase, nitrite reductase, fumarate reductase and hydrogenase activities as well as in cytochrome C552 biosynthesis. The use of an antiserum specific for nitrate reductase shows that the nitrate reductase protein is probably missing. A single mutation is responsible for this phenotype: the gene affected, nir R, is located close to tyr R i.e. at 29 min on the chromosomal map.

  6. Synthesis methodology and applied heterocyclic chemistry; Methodologie de synthese et chimie heterocyclique appliquee

    Energy Technology Data Exchange (ETDEWEB)

    Suzenet, F

    2007-11-15

    Among the researches activities presented in this work, is described the synthesis of extracting molecules for the reprocessing of nuclear wastes. The use of some elaborated ligands for the detection of metallic cations has been considered. (O.M.)

  7. Soil trace metals and analytical chemistry; Metaux traces des sols et chimie analytique

    Energy Technology Data Exchange (ETDEWEB)

    Bermond, A. [Institut National Agronomique, Lab. de Chimie Analytique, 75 - Paris (France)

    2004-09-01

    The hazard due to the presence of large amounts of trace metals in some soils is strongly related to what we call the speciation of these metals. This so-called speciation is usually performed with extracting reagents, that is to say corresponds to the use of chemical reagents in order to extract metallic cations from a soil sample and to quantify the extracted metals in the solution when equilibrium is reached. This paper is more particularly devoted to the use for this purpose of two reagents, hydrogen peroxide and EDTA. (author)

  8. Chimie organique prébiotique dans des environnements planétaires.

    Science.gov (United States)

    Raulin, F.

    1989-04-01

    Life probably appeared on the Earth after a long chemical evolution. The transformation of simple organic molecules, through physical chemical processes of increasing complexity, would have allowed the formation of the biomacromolecules. The origin of these simple organics, precursors of the prebiotic chemistry, is still controversial (atmosphere? oceans? meteoritic or cometary impacts?). However their nature is now well defined. When considering the atmospheric composition of the different planets of the solar system, one can observe a good agreement between previsions of the organics likely to be present, from the data of simulation experiments, and observations. In particular, the discovery of a complex organic chemistry on Titan, in spite of the absence of water, confirms that the best prebiotic atmosphere implies the presence of methane and nitrogen as major atmospheric components and a low mole fraction of hydrogen.

  9. Raw materials for the energy supply of the future. Geology, markets, environmental influences; Rohstoffe fuer die Energieversorgung der Zukunft. Geologie, Maerkte, Umwelteinfluesse

    Energy Technology Data Exchange (ETDEWEB)

    Hagelueken, Christian [Umicore, Hanau-Wolfgang (Germany); Thauer, Rudolf K. [Max-Planck-Institut fuer Terrestrische Mikrobiologie, Marburg (Germany); Buchholz, Peter [Bundesanstalt fuer Geowissenschaften und Rohstoffe, Hannover (Germany). Deutsche Rohstoffagentur; Herzig, Peter [GEOMAR Helmholtz-Zentrum fuer Ozeanforschung Kiel (Germany); Gutzmer, Jens [Technische Univ. Bergakademie Freiberg (Germany); Helmholtz-Institut Freiberg fuer Ressourcentechnologie (Germany); Littke, Ralf [Rheinisch-Westfaelische Technische Hochschule (RWTH), Aachen (Germany); Angerer, Gerhard; Wellmer, Friedrich-Wilhelm

    2015-11-15

    More and more metals are needed to expand modern energy technologies, but we can not completely dispense with fossil raw materials and biomass in the near future either. Are the incidence of the conversion of energy sources sufficient? The analysis of the academy project ''Energy Systems of the Future'' (ESYS) comes to the conclusion that geologically enough raw materials are available. The challenge, however, is to make the supply safe, affordable and environmentally and socially compatible. The analysis explains the mechanisms of action on the global commodity markets and identifies supply risks. These include, for example, sudden demand on the international markets as well as the unequal distribution of the world's raw material reserves. This is followed by the analysis approaches, in order to recognize warning signals for potential raw material bottlenecks in time, to develop evasive strategies and to secure the raw material supply for the energy turnarounds. For example, the expansion of recycling can help to reduce the dependence on metal imports. In mining, on the other hand, innovative technologies have to be developed in order to improve the exploration and utilization of the deposits. By establishing binding environmental and social standards, the extraction of raw materials could also become more sustainable. The analysis also highlights the importance of bioenergy and fossil raw materials, such as oil and natural gas, for energy generation. The authors describe the advantages and disadvantages of these energy carriers and the measures that can be used to reduce environmental pollution such as greenhouse gas emissions. [German] Fuer den Ausbau moderner Energietechnologien werden immer mehr Metalle benoetigt, doch auch auf fossile Rohstoffe und Biomasse koennen wir in naher Zukunft nicht vollstaendig verzichten. Reichen die Vorkommen zur Umsetzung der Energiewende aus? Die Analyse des Akademienprojekts ''Energiesysteme der Zukunft'' (ESYS) kommt zu dem Ergebnis, dass geologisch gesehen genuegend Rohstoffe zur Verfuegung stehen. Die Herausforderung besteht jedoch darin, die Versorgung sicher, bezahlbar sowie umwelt- und sozialvertraeglich zu gestalten. Die Analyse erlaeutert die Wirkmechanismen auf den globalen Rohstoffmaerkten und identifiziert Versorgungsrisiken. Dazu zaehlen zum Beispiel ploetzliche Nachfrageschuebe auf den internationalen Maerkten sowie die ungleiche Verteilung der Rohstoffvorkommen auf der Welt. Daran anschliessend liefert die Analyse Ansaetze, um Warnsignale fuer potenzielle Rohstoffengpaesse rechtzeitig zu erkennen, Ausweichstrategien zu entwickeln und die Rohstoffversorgung fuer die Energiewende zu sichern. So kann zum Beispiel der Ausbau des Recyclings dazu beitragen, die Abhaengigkeit von Metallimporten zu reduzieren. Im Bergbau wiederum gilt es, innovative Technologien zu entwickeln, um die Erkundung und Nutzung der Lagerstaetten zu verbessern. Durch die Festlegung verbindlicher Umwelt- und Sozialstandards koennte die Rohstoffgewinnung darueber hinaus nachhaltiger erfolgen. Die Analyse beleuchtet ausserdem die Bedeutung der Bioenergie und fossiler Rohstoffe wie Erdoel und Erdgas fuer die Energiewende. Die Autoren beschreiben, welche Vor- und Nachteile diese Energietraeger mit sich bringen und durch welche Massnahmen Umweltbelastungen wie Treibhausgasemissionen reduziert werden koennen.

  10. De geologie, de bodemvorming en de waterstaatkundige ontwikkeling van het Land van Maas en Waal en een gedeelte van het Rijk van Nijmegen

    NARCIS (Netherlands)

    Pons, L.J.

    1957-01-01

    Geology, soil science and the history of water management were surveyed between the rivers Meuse and Waal. Two terrace-shaped sand plains, covered by loamy aeolian sands border the Nymegen ice-pushed ridge. Further west were well formed soils with manganese banks developed in unpushed High Terrace m

  11. Geophysik und geologie : R. Lauterbach (Editor). B.G. Teubner Verlags-gesellschaft, Leipzig, 1967. folge 11, 111 pp.,88 illus., 16 tables D.M.18.-

    NARCIS (Netherlands)

    Voo, R. van der

    1969-01-01

    This series, appearing since 1957, is devoted to various geological applications of geophysical measurements. For the reader with sufficient knowledge of the German language, it offers the possibility to form an opinion about the research in this field in eastern Europe. The 11th volume, which is re

  12. Bylaag 3 tot „Koer&’’, April en Junie, 1955: Die belang van toegepaste geologie en die werk van die geoloog in ons mineral afhanklike besawing

    Directory of Open Access Journals (Sweden)

    P. B. Ackermann

    1955-03-01

    Full Text Available Die toekomstigc ontwikkeling, welvaart en sekuriteit van ons land en die handhawing en verbetering van ons huidige lewenstandaard hang tot’n groot mate af van die doeltreffendste gebruik van ons oorvloedige mineraalhulpbronne, maar beperkte watervoorrade.

  13. The ozone hole and the 1995 Nobel prize in chemistry; Trou d`ozone et Prix Nobel 1995 de chimie

    Energy Technology Data Exchange (ETDEWEB)

    Berger, A. [Universite Catholique de Louvain (UCL), Louvain-la-Neuve (Belgium). Inst. d`Astronomie et de Geophysique G. Lemaitre

    1996-03-01

    To mark to award of the 1995 Nobel Prize in chemistry to three world renowned atmospheric chemists, this paper recalls the history of scientific progress in stratospheric ozone chemistry. Then it summarizes current knowledge of ozone-layer depletion and its impact on climate, vegetation and human health. (author). 21 refs., 12 figs.

  14. The Verwey transition in nanostructured magnetite produced by a combination of chimie douce and spark plasma sintering

    Energy Technology Data Exchange (ETDEWEB)

    Gaudisson, T.; Nowak, S.; Ammar, S. [ITODYS, Université Paris Diderot, PRES Sorbonne Paris Cité, CNRS-UMR 7086, 75205 Paris Cedex (France); Vázquez-Victorio, G.; Valenzuela, R., E-mail: raulvale@yahoo.com [Depto Materiales Metálicos y Cerámicos, Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Mexico 04510 (Mexico); Bañobre-López, M.; Rivas, J. [International Iberian Nanotechnology Laboratory, 4715-310 Braga (Portugal); Mazaleyrat, F. [SATIE, ENS Cachan, CNRS, UniverSud, F-94230 Cachan (France)

    2014-05-07

    Magnetite nanoparticles about 10 nm sized were synthesized by the polyol method. Zero-field-cooled (ZFC)-FC measurements showed a blocking temperature ∼170 K and the absence of the Verwey transition. They were subsequently consolidated by spark plasma sintering at 750 °C for 15 min, leading to a high density (92% of the theoretical density), solid body, with grains in the 150 nm range. X-ray diffraction patterns exhibited a spinel single phase with cell parameters corresponding to the magnetite structure. Magnetic measurements showed a decrease of coercivity from 685 Oe (54.5 kA/m) at 118 K to 90 Oe (7.2 kA/m) at 139 K. ZFC measurements at 25 Oe presented a three-fold magnetization increase as temperature increased; a small transition between 116 and 117.5 K, followed by a larger one from 117.6 to 124 K. The first transition can be associated with a complex crystallographic transition and delocalization of Fe{sup 2+}-Fe{sup 3+}, while the second one can be attributed to spin reorientation due to the magnetocrystalline anisotropy constant (K{sub 1}) change of sign as previously observed only in magnetite single crystals.

  15. The Verwey transition in nanostructured magnetite produced by a combination of chimie douce and spark plasma sintering

    Science.gov (United States)

    Gaudisson, T.; Vázquez-Victorio, G.; Bañobre-López, M.; Nowak, S.; Rivas, J.; Ammar, S.; Mazaleyrat, F.; Valenzuela, R.

    2014-05-01

    Magnetite nanoparticles about 10 nm sized were synthesized by the polyol method. Zero-field-cooled (ZFC)-FC measurements showed a blocking temperature ˜170 K and the absence of the Verwey transition. They were subsequently consolidated by spark plasma sintering at 750 °C for 15 min, leading to a high density (92% of the theoretical density), solid body, with grains in the 150 nm range. X-ray diffraction patterns exhibited a spinel single phase with cell parameters corresponding to the magnetite structure. Magnetic measurements showed a decrease of coercivity from 685 Oe (54.5 kA/m) at 118 K to 90 Oe (7.2 kA/m) at 139 K. ZFC measurements at 25 Oe presented a three-fold magnetization increase as temperature increased; a small transition between 116 and 117.5 K, followed by a larger one from 117.6 to 124 K. The first transition can be associated with a complex crystallographic transition and delocalization of Fe2+-Fe3+, while the second one can be attributed to spin reorientation due to the magnetocrystalline anisotropy constant (K1) change of sign as previously observed only in magnetite single crystals.

  16. Synchrotron radiation: a tool for chemical sciences investigation; Le rayonnement synchrotron au service des problematiques de la chimie

    Energy Technology Data Exchange (ETDEWEB)

    Sauvage-Simkin, M. [Synchrotron SOLEIL, L' Orme des Merisiers, Saint-Aubin, BP 48, F-91192 Gif-sur-Yvette Cedex (France)

    2011-07-01

    After recalling briefly the principles of synchrotron radiation production and its remarkable properties, the main investigation techniques used by the chemical science community is described and illustrated by recent examples of applications: X-ray absorption spectroscopy, X-ray diffraction and diffusion, electron spectroscopy, infrared spectroscopy. All these techniques have seen an enhancement of their ultimate performances in terms of acquisition rate and resolution (time, spatial, and energy domains) thanks to the sources optimization and the progress in instrumentation. The experimental possibilities offered by the most recent European sources are listed, with the emphasis on SOLEIL and ESRF, together with a brief survey of the future opportunities provided by the so-called fourth generation sources. (author)

  17. Contribution to the solution chemistry of uranium (6); Contribution a la chimie de l'uranium (6) en solution

    Energy Technology Data Exchange (ETDEWEB)

    Tsymbal, C. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1969-07-01

    In the first part, a potentiometric study of the complexes formed by the uranyl ion with the hydroxy ligand has been performed. evidence has been presented for the existence of the following complexes with their respective stability constants (determined at 25 deg. C in 0.1 M ClO{sub 4}Na medium): UO{sub 2}OH, logbeta{sub 1,-1}= -4.39; (UO{sub 2}){sub 2}OH, logbeta{sub 2,-1} = -2.22; (UO{sub 2}){sub 2} (OH){sub 2}, logbeta{sub 2,-2} = -6.09; (UO{sub 2}){sub 3}(OH){sub 5}, log{sub 3,-5}) = -15.64; (UO{sub 2}){sub 3} (OH){sub 7}, logbeta{sub 3,-7} = -24.03. In the second part, a similar investigation has been undertaken on the complex formed by the uranyl ion with carbonate and/or hydroxyl ligands; the latter appearing in neutral or acid media. Evidence has been presented for the existence of the following complexes and their respective stability constants, all determined at 25 deg. C in 0.1 M ClO{sub 4}Na medium: UO{sub 2}(CO{sub 3}){sub 3}, logbeta{sub 3,1,0} = 21.57. UO{sub 2}(CO{sub 3}){sub 2}, logbeta{sub 2,1,0} = 16.16; UO{sub 2}CO{sub 3}OH, logbeta{sub 1,1,-1} 4.10. In the third part, the solid phases of the system (NO{sub 3}){sub 2}UO{sub 2} - NaOH - H{sub 2}O have been investigated by the method of the residues. In this system the following compounds have been identified: U{sub 2}O{sub 7}Na{sub 2} and (NO{sub 3}){sub 2} U{sub 6}O{sub 17} in slightly acid medium. Finally, the solid phases of the system (NO{sub 3}){sub 2}UO{sub 2} - CO{sub 3}Na{sub 2} - H{sub 2}O have been investigated as before. The following compounds have been identified: CO{sub 3}UO{sub 2}, in slightly acid medium; an uranyl alkaline carbonate appearing in neutral medium with the formula (UO{sub 2}CO{sub 3}){sub 3} (NaOH){sub 2}, as well as the corresponding uranates. (author) [French] Dans la premiere partie, nous avons etudie par potentiometries les complexes formes par l'ion uranyl et le ligand hydroxyle. nous avons prouve l'existence des complexes suivants et nous avons determine leur constante de stabilite (a 25 deg. C et dans le milieu 0.1 M ClO{sub 4}Na): UO{sub 2}OH, logbeta{sub 1,-1} = -4.39; (UO{sub 2}){sub 2}OH, logbeta{sub 2,-1} = -2.22; (UO{sub 2}){sub 2} (OH){sub 2}, logbeta{sub 2,-2} = -6.09; (UO{sub 2}){sub 3} (OH){sub 5}, log{sub 3,-5}) = -15.64; (UO{sub 2}){sub 3} (OH){sub 7}, logbeta{sub 3,-7} = -24.03. Dans la deuxieme partie, nous avons etudie par potentiometrie les complexes formes par l'ion uranyle avec les ligands carbonate et hydroxyle, ces derniers apparaissant en milieu neutre ou acide. nous avons prouve l'existence des complexes suivants et nous avons determine leur constante de stabilite (a 25 deg. C et dans le mileu 0.1 M ClO{sub 4}Na): UO{sub 2}(CO{sub 3}){sub 3}, logbeta{sub 3,1,0} = 21.57. UO{sub 2}(CO{sub 3}){sub 2}, logbeta{sub 2,1,0} = 16.16; UO{sub 2}CO{sub 3}OH, logbeta{sub 1,1,-1} = 4.10. Dans la troisieme partie, nous avons etudie par la methode des restes de phases solides du sysreme (NO{sub 3}){sub 2} UO{sub 2} - NaOH - H{sub 2}O. Nous avons mis en evidence, les composes suivants: U{sub 2}O{sub 7}Na{sub 2}, en milieu alcalin; U{sub 6}O{sub 19}Na{sub 2}, en milieu neutre; U{sub 12}O{sub 37}Na{sub 2} et(NO{sub 3}){sub 2} U{sub 6}O{sub 17}, en milieu legerement acide. Enfin, dans la quatrieme partie, nous avons etudie par la methode des restes, les phases solides du systeme (NO{sub 3}){sub 2}UO{sub 2} - CO{sub 3}Na{sub 2} - H{sub 2}O. Nous avons mis en evidence, en plus des uranates, les deux composes suivants: CO{sub 3}UO{sub 2}, en milieu legerement acide; et un carbonate d'uranyle alcalin apparaissant en milieu neutre de formule brute (UO{sub 2}CO{sub 3}){sub 3}(NaOH){sub 2}. (auteur)

  18. Semiannual Report of the Chemistry Department, June--November 1966; Rapport semestriel du departement de chimie, juin--novembre 1966

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1967-07-01

    This semiannual report of the Chemistry Department of the Cea of Fontenay-aux Roses, presents in its first part researches on the chemical analysis, the treatment of fairly and slightly active effluents, the uranium treatment, studies on electrometallurgy, studies on corrosion and studies on filtration and elimination on sea water of hard compounds. The second part is devoted to the study of aqueous reprocessing of irradiated fuels (laboratory and pilot plant), anhydrous reprocessing, actinides elements isotopes preparation and study, fission products concentrated solution vitrification study and fundamental studies on acid-base properties. (A.L.B.)

  19. Supports visuels réalisés dans le cadre des travaux pratiques de Chimie Analytique (Partie II)

    OpenAIRE

    Ziemons, Eric; Lejeune, Robert; Hubert, Philippe

    2008-01-01

    Plusieurs vidéos (étalonnage des pipettes, argentimétrie: méthode de Fajans et argentimétrie: méthode de Mohr) illustrent les manipulations des travaux pratiques de 2ème Baccalauréat en Sciences pharmaceutiques.

  20. Supports visuels réalisés dans le cadre des travaux pratiques de Chimie Analytique (Partie I)

    OpenAIRE

    Ziemons, Eric; Houbart, Virginie; Lejeune, Robert; Hubert, Philippe

    2007-01-01

    Plusieurs vidéos (utilisation de la burette, calibration de la balance analytique, nettoyage de la balance analytique, gravimétrie, rinçage des pipettes, prélèvement à l'aide d'une pipette à 1 trait, prélèvement à l'aide d'une pipette à 2 traits et transfert quantitatif) illustrent le B.A.-BA des manipulations des travaux pratiques de 2ème Baccalauréat en Sciences pharmaceutiques.

  1. Reactors. Industrial processes in chemistry/petrochemistry. Catalytic reforming; Reacteurs. Procedes industriels chimie/petrochimie. Reformage catalytique

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, G. [AXENS-IFP, Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France); Joly, J.F. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France)

    2001-12-01

    The new regulatory constraints (pollution regulations: decrease of lead amount in gasolines, and energy savings) have led the industrialists to better valorize their petroleum cuts. More specific and adapted processes have then been perfected, for instance for the refining. After having recalled what types of reactions are to be promoted, how to obtain them with a good yield (thermodynamic and kinetic considerations), the authors describe 1)what types of catalysts are used for these reactions, what their activities are and how they are prepared 2)the industrial implementation of the catalytic reforming (main types of units, experimental conditions, equipments, main processes of reforming and pretreatment) and then give the performances of the catalytic reforming. (O.M.)

  2. Grade 12 Diploma Examination: Chemistry 30. June 1986. = Examen en vue du Diplome Douzieme Annee: Chimie 30. Juin 1986.

    Science.gov (United States)

    Alberta Dept. of Education, Edmonton.

    Chemistry 30 is a twelfth-grade chemistry course for students in Alberta, Canada. This document is a final test for the course. Both English and French versions of the test are provided. Intended for administration during June 1986, it contains 56 multiple-choice questions and three written-response problems. Two-and-one-half hours are allowed for…

  3. Grade 12 Diploma Examination: Chemistry 30. January 1988 = Examen en vue du diplome douzieme annee: Chimie 30. Janvier 1988.

    Science.gov (United States)

    Alberta Dept. of Education, Edmonton.

    Chemistry 30 is a 12th-grade science course for students in Alberta, Canada. This document is the final test for the course. Intended for administration during January 1988, it contains 56 multiple-choice questions and three written-response questions. Two-and-one-half hours are allowed for completing the test. No answer key is included since…

  4. Grade 12 Diploma Examination: Chemistry 30. June 1989 = Examen en vue du diplome douzieme annee: Chimie 30. Juin 1989.

    Science.gov (United States)

    Alberta Dept. of Education, Edmonton.

    Chemistry 30 is a 12th-grade science course for students in Alberta, Canada. This document is the final test for the course. Intended for administration during June 1989, it contains 56 multiple-choice questions and 3 written-response questions. Two-and-one-half hours are allowed for completing the test. No answer key is included since scoring is…

  5. Grade 12 Diploma Examination: Chemistry 30. January 1989 = Examen en vue du diplome douzieme annee: Chimie 30. Janvier 1989.

    Science.gov (United States)

    Alberta Dept. of Education, Edmonton.

    Chemistry 30 is a 12th-grade science course for students in Alberta, Canada. This document is the final test for the course. Intended for administration during January 1989, it contains 56 multiple-choice questions and three written-response questions. Two and one-half hours are allowed for completing the test. No answer key is included since…

  6. Grade 12 Diploma Examination: Chemistry 30. June 1988 = Examen en vue du Diplome Douzieme Annee: Chimie 30. Juin 1988.

    Science.gov (United States)

    Alberta Dept. of Education, Edmonton.

    Chemistry 30 is a 12th-grade chemistry course for students in Alberta, Canada. This document is the final test for the course. Intended for administration during June, 1988, it contains 56 multiple-choice questions and three written-response questions. Two-and-one-half hours are allowed for completing the test. No answer key is included since…

  7. TIC et enseignement de la Chimie : au-delà des discours, quels dispositifs d’enseignement pour quels apprentissages?

    Directory of Open Access Journals (Sweden)

    MARIE-THÉRÈSE SALIBA

    2012-12-01

    Full Text Available In this research we suggest to take advantage of the opportunities offered by the new information and communication technologies (NICT. This new techno-scientific process of investigation will be realized via a laboratory of CAE (Computer assisted experimentations where the computer is the learning tool that seeks in real time concrete observations. Experimental know- how, and the using of abstract representations to solve problems. To do this, we have introduced innovated courses in Didactics based on ICT/CAE in our Masters programs in the Holy Spirit University of Kaslik (USEK. These courses are intended for initial and continuous training of our student-teachers in mathematics and science and technology. Subsequently, our student-teachers will use CAE with their students in high schools for teaching chemistry to test and validate the functional aspect of the environment CAE proposed. The educational validation of this paradigm will be based on the confrontation between a priori analysis and subsequent findings to measure the gap of understanding that students have acquired.

  8. COMPLEXES DE CUIVRE D’INTERET BIOINORGANIQUE MODELISANT LES METALLO-ENZYMES : SYNTHESE ET CARACTERISATION DES COMPLEXES DE CUIVRE(II) AVEC DES LIGANDS DERIVES DES IMIDAZOLES

    OpenAIRE

    BELFILALI, IMANE

    2010-01-01

    La chimie de coordination est une discipline qui fait l’interface entre la chimie organique et la chimie inorganique. Elle a connue un développement tant dans le domaine de la chimie structurale et analytique que dans celui des applications biologiques.

  9. Geology and uranium occurrences in the Forez tertiary plain (in the French 'Massif Central'); Geologie et mineralisations uraniferes de la plaine tertiaire du Forez (Massif Central francais)

    Energy Technology Data Exchange (ETDEWEB)

    Duclos, P. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses - 92 (France). Centre d' Etudes Nucleaires

    1967-01-01

    In the first part, the observations made during the geological survey of the Forez Tertiary plain (in the French 'Massif Central') are recalled. Then, using various methods, the author lists the formations according to chronology. Finally, a reconstitution of the geological history of this subsidence basin is attempted. In the second part, the occurrence of 17 uranium bearing geochemical anomalies is commented upon. Each of these various anomalies is given a place on the stratigraphic scale. This enables the author to put the successive phases of uranium deposition into their proper perspective in the history of the plain. In conclusion, the author points out the usefulness of these uraniferous geochemical anomalies. (author) [French] Dans la premiere partie, l'auteur rappelle les observations faites au cours de l'etude geologique de la plaine tertiaire du Forez (Massif Central francais). Puis se servant de differentes methodes, il etablit une chronologie des formations. Enfin, il termine par un essai de reconstitution de l'histoire geologique de ce bassin de subsidence. Dans la deuxieme partie, il commente la decouverte de 17 anomalies geochimiques uraniferes. Il situe ces differentes anomalies dans la serie stratigraphique. Ceci lui permet de replacer les depots successifs de l'uranium dans l'histoire de la plaine. Enfin, il indique l'interet de ces anomalies geochimiques uraniferes. (auteur)

  10. The largest Swiss diffusion storage system - Geology, petrophysics, hydro-geology and experience gained from the realisation of heat probes; Groesster saisonaler Diffusionsspeicher der Schweiz D4 in Root (LU): Geologie, Petrophysik, Hydrogeologie und Erfahrungen mit der Realisation des Sondenfeldes

    Energy Technology Data Exchange (ETDEWEB)

    Keller, B.

    2007-07-15

    This article takes a look at a large heat-diffusion storage system that is to be implemented in stages at a business and innovation centre in Root, near Lucerne in Switzerland. The aim is to meet 50 percent of energy needs using renewable energy. Apart from conventional oil and gas-fired systems, a combined heat and power (CHP) unit, heat and cold storage, a solar roof and photovoltaics, a seasonal underground diffusion storage system is used. This storage system is 'filled' with heat in summer from the roof and waste heat. It then functions in winter as a heat source. The system features two fields of 49, 160 metre-long heat probes that use a volume of 376,000 cubic metres of rock. The dimensioning of the rock-storage system was simulated using the PILESIM program and the first field was implemented in 2001. A geological overview is presented and the physical properties of the rock structures used are discussed. The temperature profile measured is presented and the precautions taken as a result of the possibility of meeting pockets of natural gas are discussed. Know-how gained from the implementation of the first probe field is discussed.

  11. Geology and hydrocarbon potential of the extensive carbonate-sand barrier zone of the Stassfurt Carbonate in Mecklenburg-West-Pommerania; Zur Geologie und Kohlenwasserstoff-Fuehrung der regionalen Karbonatsand-Barrenzone des Stassfurtkarbonats in Mecklenburg-Vorpommern

    Energy Technology Data Exchange (ETDEWEB)

    Rasch, H.J. [Erdoel-Erdgas Grimmen GmbH, Grimmen (Germany); Zagora, K. [Erdoel-Erdgas Grimmen GmbH, Grimmen (Germany); Schlass, H. [Erdoel-Erdgas Grimmen GmbH, Grimmen (Germany); Muenzberger, E. [Sektion Geologie, Greifswald Univ. (Germany); Beer, H. [Erdoel-Erdgas Grimmen GmbH, Grimmen (Germany)

    1993-12-31

    On the basis of what is known about the Luetow oil field, a brief description is given of the structural situation and facies distribution in the area of the extensive carbonate-sand barrier in the northeastern part of Mecklenburg-West-Pommerania. The authors then deal with the sedimentation pattern of the Stassfurt carbonate in the area of the shelf, cycles and major rhythms, facies distribution, the carbonate reservoir sequence, the effects of diagenetic changes on the storage capacity of the sediment pores and the possible development of fracture storage capacity. A brief account of the source rock potential and the maturation history of the organic matter leads up to a description of the migration and accumulation processes. Finally, the characteristics of the traps in the area of the carbonate-sand barrier are described as well as how the traps filled up. (orig.) [Deutsch] Ausgehend von der Erdoellagerstaette Luetow werden die Aufschlussverhaeltnisse und der geologische Rahmen im Bereich der regionalen Karbonatsandbarre Nordost-Mecklenburg-Vorpommerns skizziert. Es folgen Sedimentationsmuster fuer das Stassfurtkarbonat im Bereich der Plattform mit der Ausbildung von Zyklen und Grossrhythmen, das Verteilungsprinzip und das Ausbildungsprofil der Karbonatspeicher, die Veraenderungen der Porenspeichereigenschaften durch die Diagenese, einschliesslich moeglicher Kluftspeicherausbildung. Eine Kurzcharakteristik ueber das Muttergesteinspotential und die Reifeentwicklung der organischen Substanz leitet schliesslich zu den Prozessen der Migration und Akkumulation ueber. Abschliessend werden die Fallencharakteristik und der Vorgang der Fallenfuellung im Bereich der Karbonatsandbarre dargestellt. (orig.)

  12. Contribution to the geology of the Niari basin: sedimentology and metallogeny of the mining region; Contribution a la geologie du Bassin du Niari sedimentologie et metallogenie de la region miniere

    Energy Technology Data Exchange (ETDEWEB)

    Bigotte, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1956-01-15

    This thesis is divided in two parts: a detailed petrographical and stratigraphical study of the upper layers of calcareous schist in Congo which lead to some sedimentological considerations, and a metallogenic study of the ores of Niari basin which lead to a theoretical description of the metallogeny in Congo. In the first part, after a brief description of the methods used, a petrographical survey of the rocks of the upper layers of calcareous schist of the Boko-Congo area is given as well as sedimentological conclusions and stratigraphical data. The studies and conclusions related to this limited area are extended to a region scale. A structural study and precised descriptions of this region lead to an attempt of tectonic explanation. In the second part, an inventory and description of known mineralisation points in the Niari basin are given and in particular the detailed descriptions of four deposits: La Grande-Mine, M'Passa, Diangala and Djenguile. The interpretations and conclusions are based on the study of the general characters of the mineralisation in Niari basin and its comparison with the mineralisation in Katanga (now Shaba region) and North Rhodesia (now Zambia). (M.P.)

  13. Présentation de Paul Colonna

    OpenAIRE

    Corvol, Pierre

    2013-01-01

    Cher Collègue, Cher Paul Colonna, Il y a moins de vingt ans est apparue dans le monde une nouvelle chimie, la chimie verte. Cette chimie est une alternative à l’utilisation du carbone fossile et d’autres types d’énergie non renouvelables (gaz, charbon). La chimie traditionnelle à base de pétrole est certes performante, créative, compétitive, et répond bien à nos besoins, mais elle est aussi polluante et épuise les ressources de carbone fossile. La chimie verte se développe à côté de la chimie...

  14. A Second Life : German Cinema's First Decades

    NARCIS (Netherlands)

    1996-01-01

    De Duitse film is het bekendst om zijn kunstfilms en zijn geschiedenis van eminente regisseurs. De aandacht voor deze twee heeft aandacht voor de populaire film in Duitsland vertroebeld. 'A Second Life' doet een soort van archeologie naar deze grotendeels over overschaduwde periode: namelijk de eers

  15. 2294-IJBCS-Article-Jacques Sawadogo

    African Journals Online (AJOL)

    hp

    2006-02-17

    Feb 17, 2006 ... 2Faculté des Sciences, Services de Chimie Analytique et Chimie des ... diffraction (XRD), Scanning Electron Microscopy (SEM) and gravimetric analysis show that they are ... of semiconductor materials (MoSe2 and WSe2.

  16. Uranium chemistry in blood and aqueous media. Techniques of studies; Chimie de l`uranium en milieux aqueux et sanguin. Techniques d`etudes

    Energy Technology Data Exchange (ETDEWEB)

    Scapolan, St.

    1996-11-01

    The object of this report in a first step, is to understand the chemistry of uranium in aqueous phase by specifying the behavior of this element in function of several parameters such PH, concentration of present species, temperature, ionic force. In a second step, investigation techniques are reviewed: X rays diffraction, potentiometric titrations, polarography, spectrophotometry, NMR of {sup 13}C, {sup 31}P, {sup 17}O, capillary electrophoresis, laser detection. The third part brings elements to understand the uranium complexation in blood medium.

  17. Institute for separation chemistry of Marcoule I.C.S.M; Institut de chimie separative de Marcoule I.C.S.M

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    Institute for Separation Chemistry was created in March 2007, and the building including laboratory and offices will be opened to scientists and technicians the middle of 2008. Since resources in Uranium are scarce and wastes related to nuclear energy production are potentially dangerous, the chemistry associated to nuclear energy production always followed the principles of green chemistry: close the life-cycle of material and fuel, minimize wastes and ascertain the acceptability by a society via knowledge of chemistry and physical chemistry involved in processes. The Institute is devoted to chemistry at the service of the nuclear energy of the future, seen as an actor for sustainable development compatible with limited resources and chemical preservation of the atmosphere. Progresses in fundamental research, based on publication and education of students, engineers and young scientists, will be focused along seven identified directions, devoted to scattering and diffraction, microscopies and mainly mesoscopic modelling. The goals of the teams are described in this booklet, describing activities of the 28 scientists since two years. Separation chemistry, a branch of physical chemistry, is a key actor in 'green chemistry'. Nano-science and physical chemistry, at the roots of modern chemistry considering also non-covalent and long-range interactions, need to be included along the 'tools' involved in new processes. Three axis of research will be privileged: initial steps of separation, via dissolution by sono-chemical means, ion separation via colloids and complex fluids, and maintaining the separation between species involving self-repairing nano-materials, once the evolution of the interface fed from the evolving interface has been modelled. Eleven permanent staff scientists are already active since a few months on average at ICSM at the date of this report (5 CEA, 2 Universities and 4 CNRS). Teaching, scientific animation, summer schools and the common laboratory book of the UMR 5257 ICSM are managed by a team from CEA/INSTN. The activity report regroups goals of teams starting to work, together with previous recent activities of scientists now belonging to ICSM. This report describes the work done before (2003-2007) creation of ICSM by scientists now belonging to ICSM as well as the scientific work done in the first months of existence of ICSM, in the form of scientists integrated in host laboratories. Work done before is described on pages with a frame concern research performed before by scientists now staff permanent scientists at ICSM and related to the goals of ICSM. ICSM will be build by conjunction of the knowledge of scientists joining the group: at the date of writing - ten months before opening of the laboratory - 1/4 of the total number of permanent scientists have already joined the UMR 5257 and convene once every month. The report could have been presented either in administrative order, i.e. by the 'number' of the team, or starting from analysis of needs in nuclear and green chemistry. We have chosen the chronological order, i.e. the order of effective starts of experiments made by permanent ICSM staff.

  18. Chemical industry, how to adapt and invest facing new regulations; Chimie, comment s`adapter et investir face aux nouvelles regles?

    Energy Technology Data Exchange (ETDEWEB)

    Paules, B. [Elf Atochem, 92 - Puteaux (France). Direction Technique

    1997-12-31

    In order to reduce NOx emission levels from a fuel oil or gas burning boiler for a chemical plant, a system using injection of gaseous ammoniacal compounds in fumes combined to hydrogen injection for controlling reaction kinetics, is presented (Thermal De-NOx process from Exxon Research and Engineering); its implementation in a cogeneration plant (gas and fuel oil) is described. NOx, NH{sub 3} and oxygen are combined to form nitrogen and water. The process equipment and control system are presented. Emission levels are compared to limit values according to the system configuration (boiler or turbine) and to post-combustion operation

  19. Elaboration de revêtements à base d'huile végétale par chimie thiol-X photoamorcée

    OpenAIRE

    Zhao, Yu Hui

    2015-01-01

    Two types of coatings constituted about 80 wt% of vegetable oil were prepared by photoinitiated thiol-X chemistry. The first one has been prepared by crosslinking of native and stand linseed oil triglycerides in the presence of 0.5 equivalent of various thiols (SH/ene) under air and UV radiation, without photoinitiator or solvent. The oxidation of fatty acids has shown a beneficial effect on the thiol-ene addition as well as on the final properties of coatings. This process is thus an interes...

  20. Industrial applications of membrane processes in chemistry and energy generation; Applications industrielles des procedes membranaires en chimie et production d'energie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    The French membranes club (CFM), with the sustain of the French institute of petroleum (IFP) has organized this meeting which aims to present the most recent industrial realizations in the domain of membrane processes in the chemistry and energy generation sectors. This document gathers the abstracts of the presentations: 1 - hydrogen purification and CO{sub 2} extraction: development of polymer matrix and metal nano-particulate hybrid membranes for selective membrane applications; study of silicone-based mixed matrix membranes for hydrogen purification via inverse selectivity principle; CO{sub 2} capture from gaseous effluents for its sequestration: role and limitations of membrane processes; membranes and processes for the abatement of the acid gas content of smokes; new structural model for Nafion{sup R} membranes, the benchmark polymer for low temperature fuel cells; 2 - molecular screen-based membranes: MFI-alumina nano-composite ceramic membranes: preparation and characterization, gaseous transport and separation; characterization and permeation properties of supported MFI membranes; in-situ measurement of butane isomers diffusion in MFI zeolite membranes through transient permeation tests; 3 - vapors separation: stability of silver particulates in PA12-PTMO/AgBF{sub 4} composite membranes and its effect on the easier ethylene transport inside these membranes; 4 - separation of liquid organic mixtures: isomers separation using cyclo-dextrins bearing membranes: application to the extraction and separation of xylene isomers; electrodialysis in organic environment: application to the electro-synthesis; study of polymer materials permeability; 5 - treatment of industrial waters: use of NanoFlux software in the modeling of nano-filtration membrane processes in the chemical industry: elimination of sulfate impurities from 'Chloralkali' brines; ultra-filtration of a wastewater containing partially emulsified oil; efficiency of a hybrid membrane separation process for the processing of industrial effluents; 6 - membrane reactors: membrane catalytic reactors: extraction, isobutane dehydrogenation and xylenes isomerization; selective oxidation of n-butane, water treatment by gas-liquid processes; selectiveness improvement of the butadiene selective hydrogenation with the use of a membrane reactor; comparison of the efficiency of three catalytic reactors for the destruction of VOCs; 7 - gases and vapors separation: a new generation of particulate filters with catalyst impregnation for DeNox function; use of membranes for uranium enrichment: example of the EURODIF plant; inorganic membranes for integration in power generation cycles and hydrogen production; treatment of natural gas with Air Liquide-MEDAL hollow fiber membranes; 8 - liquids separation: nano-filtration in organic environment: state-of-the-art; recycling of organic compounds by inverse osmosis and seawater sulfate removing by nano-filtration; use of organic and mineral membranes in chemistry; membrane separation in chemicals manufacture; advantages and drawbacks of different membrane systems for the treatment of industrial water; concentration and recovery of organic pigments using ceramic membranes; 9 - membranes, processes and simulation: industrial experience with hybrid distillation - pervaporation or vapor permeation applications; electro-dialysis integration in amines and glycol solutions purification processes; integration of MFI membranes in the light gasoline isomerization process. (J.S.)

  1. Industrial chemistry. Tome 3, combustion and explosion of gaseous mixtures. Course and solved exercises; Chimie industrielle. Tome 3, combustions et explosions des melanges gazeux. Cours et problemes resolus

    Energy Technology Data Exchange (ETDEWEB)

    Lefrancois, B. [Conservatoire National des Arts et Metiers (CNAM), 75 - Paris (France)

    1999-07-01

    This book comprises a course about the combustion and explosion of gaseous mixtures, followed by 12 exercises of application with their solution. The seven chapters of the course deal successively with: 1 - general considerations about combustions and explosions: definitions, chemical equations of combustion, standard combustion and decomposition enthalpies, internal combustion energy, oxygen statement, forecasting of the explosive property, risk assessment; 2 - flame temperatures: adiabatic flame temperatures and complete reactions, adiabatic combustion pressure at constant volume, adiabatic flame temperatures and equilibrium reactions, examples of calculations; 3 - ignition temperatures: measurement (pyrometry), mechanism, delay, variations of ignition temperature, ignition of a gas mixture by adiabatic compression, ignition of a gas mixture by contact with a very hot solid, ignition temperatures and safety; 4 - flammability limits of gaseous mixtures: pure materials in air, flammable gas mixtures, safety; 5 - deflagration in gaseous phase: phenomenon, mechanism, variations of propagation velocities, jamming diameter and distance, deflagration initiated inside a tube with one end closed, deflagration inside a closed cell; 6 - detonation in gaseous phase: phenomenon, general characteristics and mechanism, variations of detonation propagation velocities, limits of detonability, priming of detonations, shock waves and combustion, deflagration primed detonation and pressures profile, comparison between the two types of heterogenous explosions (deflagration and detonation in gases); 7 - atmospheric dispersion: general aspects, Gaussian models, particular cases. (J.S.)

  2. Une histoire de la chimie atmosphérique globale : Enjeux disciplinaires et d'expertise de la Couche d'ozone et du Changement climatique

    OpenAIRE

    Briday, Régis

    2014-01-01

    Until now, the history of environmental sciences has not extensively documented the input of atmospheric chemists, who formalize the chemical reactions that take place in the atmosphere. This PhD dissertation focuses on chemistry of the global atmosphere. Atmospheric chemistry has been in the heart of the expertise on the anthropogenic destruction of the ozone layer from 1970 on. Since the end of the 1980s, atmospheric chemists have also taken part in the writing of the IPCC reports. They hav...

  3. New 'chimie douce' approach to the synthesis of hybrid nanosheets of MoS2 on CNT and their anti-friction and anti-wear properties.

    Science.gov (United States)

    Altavilla, Claudia; Sarno, Maria; Ciambelli, Paolo; Senatore, Adolfo; Petrone, Vincenzo

    2013-03-29

    Hybrid organic-inorganic oleylamine@MoS2-CNT nanocomposites with different compositions were obtained by thermal decomposition of tetrathiomolybdate in the presence of oleylamine and high quality multiwalled carbon nanotubes (CNTs) previously prepared by the CCVD technique. The nanocomposite samples were characterized by the TEM, SEM TG-MS, Raman and XRD techniques and successfully tested as anti-friction and anti-wear additives for grease lubricants.

  4. Applications of electron spin resonance to some problems of radiation chemistry; Applications de la resonance paramagnetique electronique a quelques problemes de chimie sous rayonnements

    Energy Technology Data Exchange (ETDEWEB)

    Chachaty, C. [Commissariat a l' Energie Atomique Saclay (France). Centre d' Etudes Nucleaires

    1968-06-01

    The electron spin resonance (E.S.R.) spectra of gamma irradiated polar organic glasses, at 77 K, shows a single line centered at g {approx} 2, attributed to solvated electrons. The radicals produced on scavenging this species by electron acceptors, such as aromatic hydrocarbons, nitro-compounds and azines have been studied by E.S.R. In most cases, the radicals from these solutes, the spectra of which are observed after elimination by warming of the radicals from the matrices, are produced by protonation of the anions formed by scavenging of electrons at 77 K. Thus, in the case of glassy solutions of nitro-compounds, the radicals R NO{sub 2}H are formed. They are characterized by a{sub N} = 15 G (nitrobenzene) or a{sub N} = 28 G (nitro-alkane). These radicals are also generated by U.V, photolysis at room temperature of solutions of nitro-compounds in alcohols and are shown to be the precursors of nitroxide radicals R - N - R (with N - O) observed simultaneously. Gamma irradiation of solutions of pyridine and of the three diazines, in alcohol glasses at 77 K, produces the radical formed by hydrogen addition to these compounds. The value of the coupling constant of the additional proton (7-10 G) indicates that it is bound to a nitrogen in the sp{sup 2} hydridation state. One has shown, taking pyridine as an example, that the addition to a carbon gives a much greater value of the coupling constant, of the order of 50-60 G. (author) [French] Les spectres de resonance paramagnetique electronique (R.P.E.) obtenus apres irradiation gamma, a 77 K, de verres organiques polaires tels que les alcools, comportent une bande unique centree a g {approx} 2, attribuable aux electrons solvates. On etudie par R.P.E. les radicaux provenant de leur capture par des solutes ayant une affinite electronique, en particulier les hydrocarbures aromatiques, les composes nitres et les azines. En general, les radicaux provenant de ces solutes, dont on observe les spectres apres elimination specifique des radicaux de la matrice par rechauffement, resultent de la protonation des anions formes par capture des electrons a 77 K. Ainsi, dans le cas de solutions vitreuses de composes nitres, il se forme les radicaux R NO{sub 2}H caracterises par a{sub N} = 15 G (nitrobenzene) ou a{sub N} = 28 G (nitro-alcanes). On observe transitoirement ces memes radicaux par photolyse U.V. de solutions de composes nitres dans les alcools, a temperature ambiante, dans la cavite du spectrometre et l'on montre qu'ils sont les precurseurs de radicaux nitroxydes R - N - R (avec N - O) observes simultanement. Les solutions de pyridine et des trois diazines dans les alcools, irradiees a 77 K donnent les radicaux produits par addition d'hydrogene sur ces composes. Il semble que le proton supplementaire, dont la constante de couplage est de 7 a 10 G, soit lie a un azote dans l'etat d'hybridation sp{sup 2}. On montre que l'addition sur un carbone donnerait une constante de couplage beaucoup plus elevee, de l'ordre de 50 a 60 G, dans le cas de la pyridine. (auteur)

  5. Chemistry. How to adapt and invest in front of the new rules?; Chimie. Comment s`adapter et investir face aux nouvelles regles?

    Energy Technology Data Exchange (ETDEWEB)

    Paules, B. [ELF Atochem, 92 - Puteaux (France)

    1997-12-31

    This paper is a series of transparencies about the experience of Elf Atochem company in the reduction of NO{sub x} emissions from petrochemical plants. The St Auban plant (France) is taken as a first example: description, regulations and NO{sub x} reduction goals, NO{sub x} reduction techniques (non-reheating of the combustion air, modifications on burners, injection of ammonia-compounds in smokes), results of the preliminary study on ammonia-compounds injection, application and principle of regulation. The second example concerns the development of a cogeneration system in the Marseille plant (description of existing installations, the cogeneration installation project, the regulatory context, the gas turbine and its post-combustion system, the dual-fuel system and the pollution regulations: chimney height, limit values of NO{sub x} and dust emissions). (J.S.)

  6. Physico-chimie d'intérêt astrophysique & Formation et évolution de la matière organique cométaire.

    OpenAIRE

    Fray, Nicolas

    2013-01-01

    Ce document présente une sélection des travaux que j'ai effectués entre 2004 et 2013. Ils concernent plus particulièrement la spectroscopie dans l'ultraviolet du vide, les équilibres solide - gaz à basses températures et la caractérisation de la matière organique réfractaire contenue dans les comètes. L'application de ces travaux expérimentaux en laboratoire à différents objets du système solaire est explicitée.

  7. Physical-chemistry of radionuclide/mineral surface interaction: I - Thermodynamical aspect; Physico-chimie de l`interaction radionucleides/surfaces minerales: I - Aspect thermodynamique

    Energy Technology Data Exchange (ETDEWEB)

    Cavallec, R.; Drot, R.; Hubert, S.; Simoni, E. [Experimental Research Division, Inst. de Physique Nucleaire, Paris-11 Univ., 91 - Orsay (France)

    1999-11-01

    The Eu(III), U(VI) and Cm(III) sorption onto phosphate surfaces have been performed. The solids, synthesized and characterized (crystallinity, morphology, specific area and surface acidity) in our laboratory, are the following: Th{sub 4}(PO{sub 4}){sub 4}P{sub 2}O{sub 7}, ZrP{sub 2}O{sub 7}, Zr{sub 2}O(PO{sub 4}){sub 2} and Ca{sub 10}(PO{sub 4}){sub 6}F{sub 2}. Batch experiments were carried out at room temperature by reacting the solid with ions in solution. Sorption isotherms are presented and compared to the specification diagrams of the ions in solution. (authors) 1 fig.

  8. Physical chemistry of the interface between oxide and aqueous solution; Quelques aspects de la chimie a l'interface oxyde - solution

    Energy Technology Data Exchange (ETDEWEB)

    Jolivet, J.P. [Universite Pierre et Marie Curie, Chimie de la Matiere Condensee, URA CNRS 1466, 75 - Paris (France)

    1997-07-01

    The behavior and properties of small oxide particles in aqueous suspension are dominated by the physico-chemistry of their surface. It is electrostatically charged and strongly solvated. The origin of the surface charge is discussed through the MUSIC model [Hiemstra 1996], allowing to estimate the acid-base behavior of surface oxygen atoms. The stability of aqueous dispersions of particles is analysed following the DLVO model, with a special attention on the hydration layers allowing the peptization of flocs. Different adsorption mechanisms of metal cations are presented in terms of coordination chemistry (outer- and inner-sphere complexes) emphasizing the coordinating ability of the surface towards metal complexes in solution. The anion adsorption is also studied in relation with some interesting consequences on spinel iron oxide nano-particles. (author)

  9. Concrete durability: physical chemistry of the water attack; Durabilite du beton: physico-chimie de l`alteration par l`eau

    Energy Technology Data Exchange (ETDEWEB)

    Faucon, P.

    1997-01-22

    Cement paste constitutes an basic medium, thermodynamically stable for high pH`s. For this reason, water constitutes an aggressive environment. For hydraulic structures, or nuclear waste disposal, water must be considered as a `chemical loading`. In the short- and medium-term water-degradation of cement paste is principally due to transport of matter between the healthy zone and the aggressive solution through diffusion of ionic species from the interstitial solution of the cement paste. In the long-term, dissolution of the surface may occur. Various cement pastes were prepared and leached with continually demineralized water. After a critical time, which depends on the type of paste, the dissolution of the surface layer in contact with water will control the degradation kinetics. The diffusive and chemical properties of the degraded layer are therefore fundamental for the prediction of the long-term behaviour of concrete in water. {sup 29}Si Magic Angle Spinning Nuclear Magnetic Resonance (MAS NMR) combined with {sup 27}A1 MAS NMR and {sup 57}Fe Moessbauer spectroscopy indicate that the superficial layer is formed by a CSH with a molecular structure near from the tobermorite mineral. Nuclear magnetic resonance techniques allow us to demonstrate the fundamental role of cationic substitutions occurring in the CSH during degradation on the superficial layer solubility. Our experimental results were used to model the cement paste behaviour taking into account the diffusion and the dissolution of the material. (author).

  10. Physical-chemistry of radionuclide/mineral surface interaction: II - Structural aspect; Physico-chimie de l`interaction radionucleides/surfaces minerales: II - Aspect structural

    Energy Technology Data Exchange (ETDEWEB)

    Cavallec, R.; Drot, R.; Hubert, S.; Simoni, E. [Experimental Research Division, Inst. de Physique Nucleaire, Paris-11 Univ., 91 - Orsay (France); Denauwer, Ch. [Direction du Cycle du Combustible, CEA Centre d`Etudes de la Vallee du Rhone, 30 - Marcoule (France); Ehrhardt, J.J. [Centre de Cinetique Physique et Chimique, Centre National de la Recherche Scientifique (CNRS), 54 - Villers-les-Nancy (France)

    1999-11-01

    Most of the studies on sorption processes takes into account only the thermodynamical approach and does not have paid attention to the structural aspect (i.e. structure of the surface complex, sorption mechanism). We have here considered this structural point of view using various spectroscopic methods such as photoelectron spectroscopy (XPS), laser induced fluorescence and extended X-ray absorption fine structure (EXAFS). (authors) 1 tab.

  11. European Science Notes Information Bulletin. Reports on Current European and Middle Eastern Science

    Science.gov (United States)

    1993-01-01

    Hydrolytic Routes 0 Modification and Hydrolysis of Metal Alkoxides Laboratoire de Chimie Organique et * Nanomaterials Prepared by Sol-Gel Process...gel research in France is heavily dominat- Laboratoire de Chimie Organique et Organoie- ed by chemists. Consequently, research emphasis tallique - J...section provides the titles of current projects at academic institutions in France. Overview of Research Laboratories Laboratoire de Chimie

  12. Modelling of Molecular Structures and Properties. Proceedings of the International Meeting of Physical Chemistry on Modeling of Molecular Structures and Properties in Physical Chemistry and Biophysics Organized by the Division de Chimie Physique of the Societe Francaise de Chimie Held in Nancy, France on 11-15 September 1989

    Science.gov (United States)

    1990-01-01

    et financier de nombreux organismes et entreprises auxquels va notre recon- naissance: en premier lieu l’Universit6 de Nancy I et la Municipalit6 de...physical signals in order to interpret them. Typical examples are diagnosis (in medicine, industry, finance and banking, etc.) and signal and image...at various stages of development (first demonstrators, prototypes, operational products) : agriculture, avionics and space, bank, finance and

  13. Synthese asymetrique glycidol et derives

    OpenAIRE

    2014-01-01

    La steereochilie (derive du grec ,singnifiant solide ) se refere a la chimie en trois dimensions(1) puisque la plupart des molecules sont tridimensionnelles, la stereochimie s'insere de fait dans pratiquement toute la chimie dans l'evaluation de la pensée chimique ,le concept de la sereochimie est venu relativement tard , une grande paati de la chimie ,souvent excellente de 19éme siecle, l'ingnore .

  14. International Conference on Computing Methods in Applied Sciences and Engineering (9th) Held in Paris, France on 29 January-2 February 1990

    Science.gov (United States)

    1990-02-02

    ULTION NUMERIQUE EN PHYSIQUE ET CHIMIE COMPUTA TIONAL PHYSICS AND CHEMISTRY_~ Localized basis functions and other computational Improvements in...La r6solution des problbmes complexes issus do la simulation num~rique en hypersonique, en micro- 6lectronique, en chimie quantique , en combustion ou...Science, Courant Inst.. New York University, 1986. 344 SIMULATION NUMERIQUE EN PHYSIQUE ET CHIMIE COMPUTATIONAL PHYSICS AND CHEMISTRY tI Localized

  15. Recent Advances in Supramolecular Assemblies with Nucleic Acids

    Science.gov (United States)

    2007-08-29

    Chairman 3:00-3:30 Jean Herscovici, Ecole Nationale Supérieure de Chimie de Paris (France) “Lipopolythioureas: a New Efficient Non Cationic System...DNA nanostructures” 10:00-10:30 Ivan Huc, Institut Européen de Chimie Biologie (IECB), Bordeaux (France) “Artificial Double Helical...Ecole Nationale Supérieure de Chimie de Paris (France) “Lipopolythioureas: a New Efficient Non Cationic System for Gene Delivery” Abstract

  16. Interfacial Effects and Organization of Inorganic-Organic Composite Solids.

    Science.gov (United States)

    1998-05-20

    FRANCE; Jean-Marc Fabre, Univ de Montpellier II, Lab de Chimie Organique Structurale, Montpellier, FRANCE Layered metal (IV) hydrogen phosphatei (forms...Fluid Laboratory, Cranbury, NJ; Clement Sanchez, Univ Pierre et Mane Curie, Chimie de la Mauere Condensee, Paris, FRANCE Hydrolysis and condensation...of Geosciences, Pnnceton, NJ; Mohamed Haouas, Univ Louis Pasteur, RMN et Chimie du Solide. Strasbourg. FRANCE; Francis B. L. Taulelle, Univ Louis

  17. International Meeting on Cholinesterases (5th) Held in Madras, India on 24-28 September, 1994.

    Science.gov (United States)

    1994-09-01

    Masson3. 1- Lab. d’entomologie, Universith Paul Sabatier, 118 route de Narbonne, 31062 Toulouse, France; 2- Lab. IMRCP, groupe de Chimie organique ...LABELING STUDIES ON CHOLINESTERASES. Maurice Goeldner. Laboratoire de Chimie Bio- Organique , URA 1386 CNRS, Facult6 de Pharmacie, Universitd Louis...CHOLINESTERASES. Isabelle Schalk, Christine Loeb, Florian Nachon, Laurence Ehret-Sabatier and Maurice Goeldner. Laboratoire de Chimie Bio- Organique - URA

  18. International Conference on Organometallic Chemistry (13th) Held in Torino, Europe on 4-9 September 1988. Abstracts

    Science.gov (United States)

    1988-09-09

    VINYLCYCLOBUTANE SYSTEMS Titus A. 3enny, Institut de chimie organique , Universlt6 de Fribourg, CH-1700 Fribourg, Switzerland Although facile ring opening of...Didier Aetruc Laboratoi , do Chimie organique at OrganowdtatZique, U.A. CURS NO 35 Univeraitd de Bordeauz 1, 351, coure de la UL.bdration, 33400 Tatence...Etienne and Hervd des Abbayes Laboratoire de Chimie Organique des Eldments de Transition, UA CNRS 322 Universitd de Bretagne Occidentale, 29287 Brest

  19. Quantum chemistry and relativity: exploring the physical and chemical properties of the complexes of heavy elements; Chimie quantique et relativite. Exploration des proprietes physiques et chimiques des complexes d'atomes lourds

    Energy Technology Data Exchange (ETDEWEB)

    Vallet, V. [Munich Univ., Institute for Theoretical Chemistry, Technical (Germany)

    2003-01-01

    Molecular and nano-molecular systems containing rare earth and actinides elements have extraordinary chemical and physical properties. Computer simulations using quantum chemistry methods can play an important role in many investigative procedures and provide help in understanding the microscopic nature of the interactions governing these macroscopic properties. The recent theoretical efforts have been devoted to the development of accurate and efficient methods that take into account all important interactions influencing the electronic structures, such as electron correlation and relativity. In particular, we illustrate the importance of relativity on chemical and spectroscopic properties. We will then focus on the modelling aspects of solution chemistry. (author)

  20. Theoretical study of the electronic structure of f-element complexes by quantum chemical methods; Analyse de la structure electronique des complexes contenant des elements F par des methodes de la chimie quantique

    Energy Technology Data Exchange (ETDEWEB)

    Vetere, V

    2002-09-15

    This thesis is related to comparative studies of the chemical properties of molecular complexes containing lanthanide or actinide trivalent cations, in the context of the nuclear waste disposal. More precisely, our aim was a quantum chemical analysis of the metal-ligand bonding in such species. Various theoretical approaches were compared, for the inclusion of correlation (density functional theory, multiconfigurational methods) and of relativistic effects (relativistic scalar and 2-component Hamiltonians, relativistic pseudopotentials). The performance of these methods were checked by comparing computed structural properties to published experimental data, on small model systems: lanthanide and actinide tri-halides and on X{sub 3}M-L species (X=F, Cl; M=La, Nd, U; L = NH{sub 3}, acetonitrile, CO). We have thus shown the good performance of density functionals combined with a quasi-relativistic method, as well as of gradient-corrected functionals associated with relativistic pseudopotentials. In contrast, functionals including some part of exact exchange are less reliable to reproduce experimental trends, and we have given a possible explanation for this result . Then, a detailed analysis of the bonding has allowed us to interpret the discrepancies observed in the structural properties of uranium and lanthanides complexes, based on a covalent contribution to the bonding, in the case of uranium(III), which does not exist in the lanthanide(III) homologues. Finally, we have examined more sizeable systems, closer to experimental species, to analyse the influence of the coordination number, of the counter-ions and of the oxidation state of uranium, on the metal-ligand bonding. (author)

  1. Chimie du glycérol pour la synthèse de dérivés du glycérol applicables comme solvants ou diluants réactifs

    OpenAIRE

    Sambou, Sophie

    2005-01-01

    Confrontés aux problèmes des composés organiques volatils et des solvants toxiques notamment les éthers de glycol, nous avons exploité cette opportunité pour développer la synthèse de dérivés de glycérol. Deux familles de dérivés du glycérol ont été retenus : les éthers de glycérol à chaîne alkyle courte (C1-C3) pour une application en tant que solvant et les acrylates et méthacrylates de glycérol pour une application en tant que diluants réactifs. Une approche de synthèse dirigée a consisté ...

  2. {sup 63}Ni and {sup 137}Cs chemistry in the soil-plant system; Chimie de {sup 63}Ni et de {sup 137}Cs dans le systeme sol-plante

    Energy Technology Data Exchange (ETDEWEB)

    Pinel, F

    2002-06-01

    The treatment and storage of radioactive waste are the responsibility of the ANDRA (The french agency for the management of radioactive wastes). The impact to man, via the entry in the human food chain depends on the mobility of each radionuclide in soil, root uptake and the subsequent redistribution in the plant. The distribution coefficient, Kd, is thought to be a good, estimator of bioavailability. We have investigated a large number of plant species (11 for caesium and 7 for nickel) in contact with contrasting soils under controlled conditions. Nickel adsorption has also been measured under controlled conditions. Particular attention has been paid to the consequences of modification of soil properties in the rhizosphere. This study confirms that the value of Kd is a good indicator of bioavailability of both nickel and caesium and that the value of Kd measured in dilute suspension may be extrapolated to that under in situ conditions. The value of Kd depends on soil pH, solution ionic strength, the presence of complexing ligands and redox conditions. The differences observed between species in nickel uptake may often be related to changes in rhizosphere pH and parallel modifications in Kd. The translocation of nickel from roots to shoots for a given species depends on the conditions of growth, due in part to access to different pools of soil nickel. (author)

  3. Construction de la professionnalité en formation initiale : regards croisés sur l’évolution d’une enseignante-stagiaire en physique chimie

    OpenAIRE

    Perez-Roux, Thérèse; Briaud, Philippe

    2007-01-01

    International audience; La formation initiale des enseignants dans les instituts universitaires de formation des maîtres (IUFM) repose sur un dispositif par alternance qui invite le stagiaire à articuler expérience pratique et acquisition de savoirs profession-nels. Cette formation intègre la complexité des compétences à construire, notamment d'ordre didactique. Dans cette étude, menée conjointement par deux chercheurs de disciplines différentes (un chercheur en sciences de l'édu-cation et un...

  4. Research on the chemistry of actinides and fission products for the development of nuclear fuel cycle; Developpement du cycle du combustible nucleaire. Recherche sur la chimie des actinides et des produits de fission

    Energy Technology Data Exchange (ETDEWEB)

    Peretroukhine, V.F. [Institute of Physical Chemistry Russian Academy of Sciences (IPC-Moscow) (Russian Federation); Lecomte, M. [CEA Valrho, Dept. Radiochimie et Procedes, 30 - Marcoule (France); David, F. [Institut de Physique Nucleaire, (IN2P3/CNRS) 91 - Orsay (France)

    2004-07-01

    The present document is prepared for CEA, IPNO and Russian Academy of Sciences administrations in compliance with the decision, accepted by the Director Committee of the three-parties-Convention on its seventh meeting in Moscow 21 May 2002. Being the general frame, determining the strategy of three-party cooperation, the Convention 1993-2003 consists of the number of contracts between organisation-participants. The present document is compiled, using annual proceedings of Director Committee and Technical Committee meetings and using published French-Russian papers and technical reports, produced in the frame of all contracts of the convention. Lists of published papers and personal summary reports of Russian participants of the contracts are presented in Appendix 1. (authors)

  5. Metallocenes: are they the triumph of modern chemistry leading to an industrial revolution?; Les metallocenes, un triomphe de la chimie moderne et peut-etre une revolution pour l`industrie

    Energy Technology Data Exchange (ETDEWEB)

    Spitz, R.; Saudemont, T. [Centre National de la Recherche Scientifique (CNRS), 69 - Villeurbanne (France). Inst. de Recherches sur la Catalyse

    1996-12-31

    Continuous advances in chemistry can find their utility in the ever increasing quality specifications required in every field of application. For major industrial polymers, the catalytically produced polyolefins, progresses were hampered by the complexity of heterogeneous catalytic processes. Novel coordination chemistry has triggered the generation of a new family of catalysts, namely titanium and zirconium metallocenes, which, when efficiently activated, are able to produce more well-defined and more controlled polymers, in agreement with industrial specifications. The production of novel polyethylenes has started on a small industrial scale. Two stereochemical parents of polypropylene (isolatic and syndiotactic polypropylene) and entirely new polymers such as poly-cyclo-olefins and syndiotactic polystyrene are likely to be developed. Large scale progresses are dependent on the suitability of the catalysts to modern processes and on the fine tuning of certain molecular characteristics of the resulting products. (authors) 10 refs.

  6. Chemistry of tetravalent actinides phosphates. The thorium phosphate-diphosphate as immobilisation matrix of actinides; Chimie des phosphates d'actinides tetravalents. Le phosphate-diphosphate de thorium en tant que matrice d'imobilisation des actinides

    Energy Technology Data Exchange (ETDEWEB)

    Dacheux, N

    2002-07-01

    The author presents in this document its scientific works from 1992 to 2001, in order to obtain the enabling to manage scientific and chemical researches at the university Paris Sud Orsay. The first part gives an abstract of the thesis on the characterizations, lixiviation and synthesis of uranium and thorium based phosphate matrix in the framework of the search for a ceramic material usable in the radioactive waste storage. The second part presents briefly the researches realized at the CEA, devoted to a reliable, independent and accurate measure of some isotopes activity. The last part presents the abstracts of researches activities from 1996 to 2001 on the tetravalent actinides phosphates chemistry, the sintering of PDT and solid solutions of PDTU and the kinetic and thermodynamical studies of the PDT dissolution. Many references and some publication in full text are provided. (A.L.B.)

  7. Local and regional factors affecting the chemistry of precipitation in the spanish basque country. L'influence des facteurs regionaux et locaux sur la chimie des precipitations au pays basque espagnol

    Energy Technology Data Exchange (ETDEWEB)

    Ezcurra, A.; Durana, N.; Casado, H. (Universidad Politecnica de Vitoria (ES)); Lacaux, J.P. (Universite Paul Sabatier, 65 - Lannemezan (FR)); Pham Van Dinh; Garcia, C.

    The study deals with near 300 rain events sampled by means of a network of five automatic devices operating from January 1986 to November 1988. The results show that, on a local-scale, the rain chemistry is affected by the marine source of gases and particles. On a regional-scale, values of pH ranging from 5.5 to 4.8 are noticed. The acidity of rain has an anthropogenic origin that is mainly linked to the NO{sub 3}- content. The acidity is reinforced by air flow from continental Europe. By contrast, rain water with a basic character is related to the air fluxes from Southern Spain that increase the rain content in Ca{sup 2+}.

  8. Mise au point d'un procédé de carboxylation par électrosynthèse en milieu co2 sous pression et application en chimie fine

    OpenAIRE

    Chanfreau, Sébastien

    2005-01-01

    Nous proposons ici d'utiliser le co2 sous pression comme solvant et réactif pour réaliser la carboxylation électrochimique du chlorure de benzyle. Un co-solvant, le dimethylformamide (DMF), est nécessaire pour permettre la solubilisation du sel assurant la conductivité du milieu. Le comportement thermodynamique du mélange co2-DMF constituant lco2ilieu électrolytique a été modélisé en utilisant le modèle de Huron-Vidal. Le milieu a été caractérisé en utilisant une microélectrode pour détermin...

  9. Synthèse de mono et diphosphines dérivées d'amino acides ou de peptides, appliquées en chimie de coordination et pour le greffage de fullerène C60

    OpenAIRE

    Minois, Pauline,

    2013-01-01

    The synthesis of secondary phosphine borane amino acids or dipeptides and their applications for the preparation of chiral ligands or for the grafting of fullerene, is described. These compounds were synthesized in good yield (up to 98%) without racemization. The principle of the synthesis is based on the alkylation of primary phosphine borane with a γ-iodo amino acid using phase transfer conditions. Tertiary diphosphine amino acids are obtained with 70% yield after a second alkylation. These...

  10. Chemistry of complexing molecules and environment. Report of the working group of the Cea ''mission environment''; Chimie des complexants en environnements. Rapport du groupe de travail de la mission environnement

    Energy Technology Data Exchange (ETDEWEB)

    Petit, J.C

    1998-07-01

    The Working group 'Chemistry of Complexing Molecules and Environment' of the Mission Environment (AG/ENV) identified themes for an original positioning of CEA on important issues of environmental research if a sufficiently strong demand appears. The research of CEA on the environment should be complementary to actions undertaken by other partners (official institutions, research organizations and industrial firms). The themes suggested are: the synthesis of new chelating molecules and new materials having specific properties, with the support of theoretical chemistry and modeling, analytical physical chemistry and speciation of species in relation to their eco-toxicity and their biogeochemical mobility in the natural environment. These themes, illustrated by examples of actions in progress at CEA or likely to be launched quickly, draw largely from recognized competences of the teams, generally developed for finalized nuclear applications: experimental, theoretical and instrumental competences. (author)

  11. Biodétérioration des structures portuaires en acier : synergie entre la physico-chimie du fer en milieu marin et les micro-organismes sulfurogènes

    OpenAIRE

    Langumier, Mikaël

    2011-01-01

    The aim of this study was to understand the mechanisms involved in marine corrosion of steel structures. These mechanisms are known to be influenced by micro-organisms, in particular by the sulphide-producing bacteria. It was then necessary to couple physico-chemical investigations with techniques of microbiology and molecular biology. In the first part of this work, a laboratory model was designed so as to study the interactions between sulphate-reducing bacteria (SRB) and the main product o...

  12. Modelling of Molecular Structures and Properties in Physical Chemistry and Biophysics, Forty-Fourth International Meeting (Modelisation des Structures et Proprietes Moleculaires en Chimie Physique et en Biophysique, Quarante- Quatrieme Reunion Internationale)

    Science.gov (United States)

    1989-09-01

    METHODOLOGY AND FIRST RESULTS ON CITRATE SYNTHASE Jean Durup Laboratoire de Physique Quantique (UA 505 du C.N.R.S.) 118, route de Narbonne, 31062 TOULOUSE...de la Brosse ESPCI 750 05 PARIS Lab. Chirn~ analyt ique 10. rue Vauquelin 75231 PARIS Cedex 55 DU-RUP j. Physique quantique FRIANT P. \\Ilie Univ. Paul...8217- Valencia Dr. Moliner 50 46100 BURJASSOT (Espagne) StMITH 3. CISI-CEA TRINQUIER C. Service de Biophysique Physique quantique Depart. de Biologie Univ. Paul

  13. Organic-inorganic hybrid materials in separation chemistry: a molecular approach towards design of purification processes; De la molecule au procede. Apports des materiaux hybrides organiques-inorganiques en chimie separative

    Energy Technology Data Exchange (ETDEWEB)

    Brandes, St.; Denat, F. [Centre National de la Recherche Scientifique (CNRS), 21 - Dijon (France); Meyer, M.; Guilard, R. [Universite de Bourgogne, Lab. d' Ingenierie Moleculaire pour la Separation et les Applications des Gaz (LIMSAG) UMR 5633 du CNRS, 21 - Dijon (France)

    2005-11-01

    Located on the campus of the Universite de Bourgogne and supported by the CNRS, the main particularity of the LIMSAG was its association with an industrial partner, the Air Liquide company. The main objectives of this unusual research unit in the French academic system was to conceive and develop new molecules and materials that exhibit suitable properties for the ultra-purification or the detection of gases. Beside these activities, a second research topic is dedicated to the decontamination of industrial waste streams containing either toxic (lead, cadmium) and/or radioactive metal ions (uranium, plutonium, americium). Specific sequestering agents have also been designed for the lead removal from municipal tap water. Grafted and sol-gel immobilized tetra-aza-macrocyclic complexes are used as specific adsorbents for the purification and detection of gases, while related functionalized silica-gels have been implemented in the solid/liquid extraction processes of metals. (authors)

  14. Caractérisation expérimentale du contact frottant disque garniture sous sollicitations sévères de freinage. Prise en compte des interactions tribologie, thermique et physico-chimie.

    OpenAIRE

    Bulthé, Anne Lise

    2006-01-01

    This study deals with the behaviour of a pad on disc rubbing contact under severe braking loadings. Those conditions are observed in railway application during an emergency stop braking or a succession of stop brakings with heat accumulation. The chosen multiphysical approach takes account of the interactions between tribology, heat science and physical chemistry. The work is presented in 4 parts.The first presents the characterization of the studied materials (an organic matrix composite and...

  15. Primary processes in radiation chemistry. LET (Linear Energy Transfer) effect in water radiolysis; Processus primaires en chimie sous rayonnement. Influence du transfert d'energie lineique sur la radiolyse de l'eau

    Energy Technology Data Exchange (ETDEWEB)

    Trupin-Wasselin, V

    2000-07-11

    The effect of ionizing radiations on aqueous solutions leads to water ionization and then to the formation of radical species and molecular products (e{sup -}{sub aq}, H{sup .}, OH{sup .}, H{sub 2}O{sub 2}, H{sub 2}). It has been shown that the stopping power, characterized by the LET value (Linear Energy Transfer) becomes different when the nature of the ionizing radiations is different. Few data are nowadays available for high LET radiations such as protons and high energy heavy ions. These particles have been used to better understand the primary processes in radiation chemistry. The yield of a chemical dosimeter (the Fricke dosimeter) and those of the hydrogen peroxide have been determined for different LET. The effect of the dose rate on the Fricke dosimeter yield and on the H{sub 2}O{sub 2} yield has been studied too. When the dose rate increases, an increase of the molecular products yield is observed. At very high dose rate, this yield decreases on account of the attack of the molecular products by radicals. The H{sub 2}O{sub 2} yield in alkaline medium decreases when the pH reaches 12. This decrease can be explained by a slowing down of the H{sub 2}O{sub 2} formation velocity in alkaline medium. Superoxide radical has also been studied in this work. A new detection method: the time-resolved chemiluminescence has been perfected for this radical. This technique is more sensitive than the absorption spectroscopy. Experiments with heavy ions have allowed to determine the O{sub 2}{sup .-} yield directly in the irradiation cell. The experimental results have been compared with those obtained with a Monte Carlo simulation code. (O.M.)

  16. Aerosol pollution in urban and industrialized area under marine influence: physical-chemistry of particles; Les aerosols de pollution en zone urbaine et industrielle sous influence marine: physico-chimie des particules

    Energy Technology Data Exchange (ETDEWEB)

    Rimetz, J

    2007-12-15

    Harbors for trade are known as highly urbanized and industrialized areas with important maritime, railway and road traffic. Industries are mainly represented by steel, cement works, and oil refineries. The maritime sector is becoming an even larger source of air pollution. Atmospheric NO{sub x}, SO{sub 2}, O{sub 3} levels and chemical analysis of airborne particulate matter were monitored in Dunkerque conurbation in 2005 and 2006. This study was included in the IRENI program. In low-pressure conditions, local pollutants are spread out far away the agglomeration, whereas, in high-pressure regimes, the atmospheric stability and sea-breezes allow an accumulation of pollutants over the urban zone. Size-resolved chemical analyses of particulate matter collected as function of the aerodynamic diameter (D{sub a}) were performed. Ions (Na{sup +}, NH{sub 4}{sup +}, Cl{sup -}, NO{sub 3}{sup -}, SO{sub 4}{sup 2-}), metals (Fe, Zn, Pb, Cd,...) and organic fraction (EC, OC) are associated with sub- or/and super-micron particles. The size, morphology and chemical species of individual particles collected selectively in the 12O{sub 3}, Fe{sub 3}O{sub 4}, PbO,... containing particles emitted in the Dunkerque harbour area and aged sea-salt aerosol particles (NaCl, NaNO{sub 3},...) from long range transport of air masses. Thin organic coatings from natural and anthropogenic origin are observed on the particles by ToF-SIMS imaging. (author)

  17. Chemistry-transport coupling and retroactive effects on material properties within the context of a deep geological repository; Couplage chimie-transport et retroaction sur les proprietes des materiaux en contexte de stockage geologique profond. Synthese des activites de recherche

    Energy Technology Data Exchange (ETDEWEB)

    Bildstein, O.

    2010-06-15

    The author gives an overview of his research and teaching activities. His researches first dealt with the development of a simulation of the chemistry/transport coupling and of the retroactive effects on transport parameters, then with the chemistry/transport modelling and its coupling with mechanics, and finally with the multi-scale investigation of porous materials. Perspectives are discussed and publications are indicated

  18. End of Century State of Science

    Science.gov (United States)

    2007-11-02

    Schelkowski Laboratoire de Chimie Theorique, Universit6 de Sherbrooke (Quebec) J1K 2R1, Canada Numerical solutions of the time-dependent Schroedinger equation... Chimie Theoretique Tomislav Cvita8 Univ. de Sherbrooke Ruder BoMkovid Institute Quebec JIK 2R1 10000 Zagreb Canada Croatia Ticijana Ban Alexander Dalgarno

  19. Synchrotron Radiation Based Study of X-Ray Absorption of Flame Generated Nanoparticles

    Science.gov (United States)

    2007-11-02

    induced ionization of nanoparticles, a proposal was prepared for submission to the French Government sponsored Programme Nationale du Physico- Chimie du...by the European Synchrotron Radiation Facility and by the French Programme Nationale du Physico- Chimie du Milieu Interstellaire. Special thanks are due

  20. West Europe Report, Science and Technology

    Science.gov (United States)

    2007-11-02

    and academic research organizations should also benefit from the research resources developed in this case. [Text] [Paris CHIMIE ACTUALITES in...extension of the knowledge gained in silicon chemistry and in polymerization and spinning techniques." [Text] LParis CHIMIE ACTUALITES in French 20 Jan

  1. 1116-IJBCS-Article-Joseph Djeugap Fovo

    African Journals Online (AJOL)

    hp

    3 Laboratoire de Chimie Organique Appliquée, Département de Chimie, Faculté des Sciences, Université de ... appliqués sur les fruits et légumes pose le plus souvent de problèmes de toxicité aux consommateurs. ..... Vegetables, Grubben.

  2. Dynamics and Stabilization of Materials Possessing High Energy Content

    Science.gov (United States)

    1989-11-13

    Mesmaeker, Service de Chimie Organique , Universite Libre de Bruxelles, Brussels, Belgium Advanced Degree Awarded Zhenyu Zhang, Ph.D. Columbia Univeristy...Northvale, NJ 07647 8. Dr. Andre M. Braun, Institute de Chimie Physique, Ecole Polytechnique Federale de Lausanne, Lausanne, SWITZERLAND 9. Dr. J

  3. Scales of Hydrogen-Bonding Workshop Held in London, England on 1-3 July 1987

    Science.gov (United States)

    1987-07-03

    UNDERSTANDING OF THE HYDROGEN-BOND INTERACTION Pierre-Charles Maria and Jean-Francois Gal Laboratoire de Chimie Physique Organique , Universite de Nice - Parc...Faculte des Sciences 2 Rue de Ia Houssiniere 44072 Nantes cedex 03 FRANCE Dr Pierre-Charles Maria Laboratorie de Chimie Physique Organic Dr Jean

  4. La cultura euboica e lo sviluppo dell’epica greca

    OpenAIRE

    Cassio, Albio Cesare

    2015-01-01

    1. A partire dagli anni’70 alcuni studiosi hanno cominciato a prendere in seria considerazione la possibilità di un influsso più ο meno profondoe più ο meno antico della culturae del dialetto dell’Eubea sull’epica greca. Il primo che si è mosso in questa direzione è stato P. Wathelet, ma si deve all’articolo di West se il problema è arrivato all’attenzione di specialisti di campi diversi (filologi, linguisti, archeologi):e questo perché l’autore di quel lavoro (uno dei massimi conoscitori di ...

  5. Symposium on Polymeric Materials for Photonic and Optical Applications Held in New York, NY on August 25-30, 1991

    Science.gov (United States)

    1992-09-01

    COOR by J. Le Moigne, A. Hilberer, C. Strazielle R = (CH2)n - H Groupe des Mat~riaux Organiques Institut de Physique et Chimie des Mat~fiaux de...Pascal Griesmar and Clement Sanchez Laboratoire de Chimie de a Matiere Condensbe Universit Pierre et Marie Curie MNA AAS Si(OEI)3 N’O 4 Place Jussieu...by f by 2&tcos 3 o( Jacques SIMON, Thierry THAMI, Michel A. PETIT--ZZ. I c s ESPCI-CNRS f = zy z~~cs sin Chimie et Electrochimie des Matriaux

  6. European Science Notes. Volume 39, Number 7.

    Science.gov (United States)

    1985-07-01

    properties. 7 3. Laboratoire de Chimie Organique 4/19/85 * Appliquge. Professor Alain Kiennemann. Mechanisms of heterogeneous and homo- geneous catalysis in...example, the "Unitg Associge creased with the formation of the asso- No. 405, Physico- chimie de la complex et ciated unit. des system interfaces" is a...d’Electrochimie et de article by listing other "laboratories" Chimie -Physique du Corps Solide in the or, in a sense, the title of the chemi- Institut Le Bel

  7. Historische waterhuishouding en historisch grondgebruik in het waterschap Regge en Dinkel

    NARCIS (Netherlands)

    Runhaar, J.; Jansen, P.C.; Timmermans, H.; Sival, F.P.; Knol, W.C.

    2003-01-01

    Ten behoeve van het waterschap Regge & Dinkel is een reconstructie gemaakt van de vroegere waterhuishouding. Op basis van digitale bestanden met bodemtype, hoogteligging, historisch grondgebruik en geologie is een schatting gemaakt van de vroegere grondwaterstanden en van de voormalige ligging v

  8. Alpheus saxidomus new species, a rock boring snapping shrimp from the Pacific coast of, Costa Rica, with notes on Alpheus simus Guérin-Méneville, 1856

    NARCIS (Netherlands)

    Holthuis, L.B.

    1980-01-01

    Recently, Professor Dr. Rudolf Fischer, Institut für Geologie und Paläontologie, Philipps-Universität, Marburg, F. R. Germany, submitted for identification some material of an Alpheid shrimp, which was found to be responsible for a considerable erosion of part of a rocky shore on the Pacific coast o

  9. De l'analyse de contextes a la pedagogie des textes (From Analysis of Context to Pedagogy of Texts)

    Science.gov (United States)

    Lehmann, Denis

    1976-01-01

    A detailed description of the "Dictionnaire contextual de francais pour la geologie." This study is used as an example of such a dictionary serving as a basic tool in the study of functional French. Such dictionaries can be useful in conceptual approaches to language learning. (Text is in French.) (AMH)

  10. In memoriam dr. Anne van Wijngaarden (1925-2004)

    NARCIS (Netherlands)

    Broekhuizen, S.; Laar, van V.

    2005-01-01

    Op 4 oktober 2004 overleed Dr. Anne van Wijngaarden op 78-jarige leeftijd in zijn huis bij Millac- Carlux, Frankrijk. Hij was een van de Nederlandse oprichters van de Vereniging voor Zoogdierkunde en Zoogdierbescherming. Nadat zijn eindexamen op de middelbare school wilde Anne aanvankelijk geologie

  11. The solid/gas catalyst against the volatile pollutants; La catalyse solide/gaz contre les polluants volatils

    Energy Technology Data Exchange (ETDEWEB)

    Erable, B.; Goubet, I.; Lamare, S.; Legoy, M.D.; Maugard, Th. [Laboratoire de Biotechnologie et Chimie Bio-Organique, CNRS FRE 2766, 17 - La Rochelle (France)

    2004-10-01

    In order to improve the classical bio-filtration systems, the LBCB (Laboratoire de biotechnologies et de chimie bioorganique) uses a new generation of bio-filter for the transformation of volatile pollutants directly in gas phase. (O.M.)

  12. New Experimental Challenges in Elemental Fluorine Chemistry; an Emerging Technology

    Science.gov (United States)

    1987-10-31

    Base Adducts," Revue de Chimie Minerale , 23, 701 (1986) (with M.A. Guerra and T.R. Bierschenk). "The Synthesis and X-ray Crystal Structures of [Au(CH 2...cobalt and Their Base Adducts," Revue de Chimie Minerale , 23, 701 (1986) (with M.A. Guerra and T.R. Bierschenk). 18. "The Synthesis and X-ray Crystal

  13. 866-IJBCS-Article-Abdoulaye Demba Ndiaye

    African Journals Online (AJOL)

    DR GATSING

    Application des méthodes statistique et analytique à l'évaluation de la ... 1 Laboratoire de Chimie de l'Eau, Institut National de Recherches en Santé Publique de Nouakchott, BP 690, ... 2 Laboratoire de Chimie de l'Eau et Environnement, Faculté des Sciences et Techniques de l'Université de ..... Ed. Dunod : Paris ; 157 p.

  14. Introduction à la théorie quantique concepts, pratiques et applications

    CERN Document Server

    Desouter, Michèle; Chapuisat, Xavier

    2017-01-01

    Introduction à la théorie quantique avec exercices corrigés pour les niveaux licence et master en physique, physico-chimie et chimie, permet d'atteindre une base solide en Mécanique Quantique et le niveau indispensable pour aborder les sujets multidisciplinaires de la recherche actuelle. En complément optionnel sur un site compagnon, des applications interactives.

  15. Organic Thin Films for Photonics Applications. Volume 14

    Science.gov (United States)

    1997-01-01

    Marguerite Barzoukas, Institut de Physique et de Chimie des Materiaux de Strasbourg, France; Valerie Alain, Mircillc Blanchard-Desce, Ecole Normale...glvt.cnrs.fr (2) LETI (CEA - Technologies Avancees) DEIN I SPE, Groupe Composants Organiques , CEA Saclay, 91191 Gif sur Yvette, France Recently...Fort, Jacques Müller, Joel Azoulay, Marguerite Barzoukas Institut de Physique et de Chimie des Materiaux de Strasbourg, Groupe d’Optique

  16. Advanced Organic Solid States Materials. Volume 173. Materials Research Society Symposium Proceedings

    Science.gov (United States)

    1990-08-08

    Cristalline, URA 144 CNRS ** Laboratoire de Physico- Chimie Thdorique, URA 503 CNRS Domaine Universitaire de Bordeaux I, 33405 - TALENCE Cddex (FRANCE...BOUYSSOUX AND S.N. KUMAR’ D6partement de Chimie Applique et Genie Chimique. CNRS-URA 417 Universit6 Claude Bernard LYON. 69622 Villeurbanne Codex...A. BARRAUD CEA-IRDI-DESICP-DLPC-SCM, CEN.Saclay, 91191 Gif sur Yvette Cedex (France) O.KAHN Laboratoire Chimle Organique , Universit#6 Paris-Sud, URA

  17. Colloquium on High Resolution Molecular Spectroscopy (8th), 19-23 September 1983 (Colloque sur la Spectroscopie Moleculaire a Haute Resolution (Huitieme), 19-23 Septembre 1983).

    Science.gov (United States)

    1983-09-23

    SPECTROSCOPIE LASER DE MOLECULES DANS LE VIOLET ET L’ULTRAVIOLET PETITS RADICAUX ET GROSSES MOLECULES ORGANIQUES . 40 mn LASER SPECTROSCOPY OF MOLECULES...34 " I i I l ll " "|| lmnm n O ~ i nn m m i - - u Emission spectrum assigned to HCCS B. COQUART Iand M. VERVLOET 2 1 Laboratoire de Chimie Physique...SUD - 91405 - ORSAY FRANCE. J. BRION, D. DAUMONT, J. MALICET LABORATOIRE DE CHIMIE -PHYSIQUE, UNIVERSITt DE REIMS 51062 - REIMS FRANCE. We present the

  18. Guided Optical Structures in the Military Environment

    Science.gov (United States)

    1986-05-01

    Stanford University, 26A--1 VERRES FLUORES POUR GUIDES DIONDE INFRA ROUGE. J. Lucas, Professeur Laboratoire de Chimie Nlindrale D, Campus de Beaulieu...do matriraux oxistont A lista& vitroux at a fortiori des matdrisux ay Ant une large bande do transparence. L# chimie des vorros est largement dominde...toutolois remarquor quo beaucoup do matdriaux, dont Is tlsau humain,l ont peu absorbants ft cette longuour d’onde. Los matE- riaux organiques , on inclut idi

  19. De l’idée au marché : l’ITERG renforce ses activités dans la chimie verte avec la plateforme CEDOP, Centre européen de développement des oléo-produits

    Directory of Open Access Journals (Sweden)

    Alfos Carine

    2012-01-01

    Full Text Available ITERG, the Industrial Technical Centre (CTI for Fats and Oils, under the supervision of the Ministry of Economy, Finance and Employment, located in Pessac has undertaken the project to build a technology platform (to be operational in early 2012 dedicated to innovation and transfer in the field of oleochemicals from experimental to semi-industrial scales. This platform, CEDOP (European Centre for the Development of Oleo-Products can offer within the same entity, expertise and scalability from laboratory to semi-industrial productions, to industrial manufacturers, processors, distributors and value chain actors of oleo-products. This project unique in its design, perfectly in tune with public policies for innovation and development of green chemistry, not only meets the needs of manufacturers and their markets but also the current socio-economic expectations in terms of environment and sustainable development. The CEDOP project total investment reached 8,700,000 € [buildings (laboratories, industrial and pilot halls, technical offices and equipment]. After the positive results of preliminary studies (competition, market research, risk assessment and the inclusion of CEDOP in the “State-Aquitaine Region Contract of Projects”, public institutions (Regional Council, State, FEDER, local and professional organization (ONIDOL brought together 85% of the project funding. Such a support reflects the confidence of the stakeholders in ITERG’s independent entrepreneurial skills in scientific and technology to meet public and professional policies, but above all in the large scope of corporate customers from different sectors of activity, potential future users of the tool. This project for research and technology transfer is fully integrated in ITERG’s development and diversification strategies and aims to develop an attractive lipochemistry-technology cluster.

  20. Application of colloidal chemistry in aqueous phase to the preparation of supported metallic catalysts: particles size and aggregation control; Application de la chimie colloidale en phase aqueuse a la preparation de catalyseurs metalliques supportes: controle de la taille et de l`etat d`agregation des particules

    Energy Technology Data Exchange (ETDEWEB)

    Pages, T.

    1998-09-16

    This work is an application of colloidal chemistry in aqueous phase on supported metal catalyst preparation. The objective is the control of particle size and aggregation. The preparation of the materials was achieved in two steps: - the synthesis of PdO hydrosols was obtained by two ways: neutralisation of the solution containing metallic salt by adding alkaline solution or by thermo-hydrolysis; the sols were then deposited on carriers (Al{sub 2}O{sub 3}, SIO{sub 2}). The use of partial charge model allowed us to determine the complexes that were able to generate PdO. The preparation of PdO from Pd(H{sub 2}O){sub 4}{sup 2+} was studied and a mechanism of oxide formation was elaborated. The neutralisation of Pd(H{sub 2}O){sub 4}{sup 2+} obtained by adding alkaline solution led to particles with an average size of 1.8 nm and a narrow particle size distribution. Only the thermo-hydrolysis of Pd(H{sub 2}O){sub 4}{sup 2+} led to particles which size is higher than 3.0 nm. In the last case, particle size is controlled by the precursor concentration (Pd(H{sub 2}O){sub 2}(OH){sub 2}) generated in the medium. We have demonstrated that particle aggregation in the sol depends on the Ph and the way of preparation. It can be controlled by adding complexing anions (Cl{sup -}, NO{sub 2}{sup -}). Concerning the deposition of sols on carriers, it led to isolated or aggregated particles according to experimental conditions. Particle size was not modified during the deposition. Moreover, in our experimental conditions, reduction of particles did not modify particle size and aggregation. An application of this original way of preparation on catalysis allowed us to demonstrate the interest of controlling particle size and aggregation. (author) 186 refs.

  1. The understanding of the R7T7 glass blocks long term behavior: chemical and transport coupling in fractured media; Comprehension de l'alteration a long terme des colis de verre R7T7: etude du couplage chimie transport dans un milieu fissure

    Energy Technology Data Exchange (ETDEWEB)

    Chomat, L

    2008-04-15

    The long term behavior of nuclear waste glass blocks depends highly on chemical reactions which occur at the surface in contact with water. Studies carried out on inactive fractured glass blocks show that fracture networks play a significant part in reactive surface area. Nevertheless, the complexity of results interpretation, due to a weak knowledge of fracture networks and local lixiviation conditions, does not allow us to comprehend the physical and chemical mechanisms involved. Model cracks are a key step to study chemical and transport coupling in fractured media. Crack lixiviation in aggressive conditions (pH{>=}11) show that the crack's position (horizontal or vertical) determines the dominant transport mechanism (respectively diffusion or convection induced by gravity). This gravity driven flow seems to be negligible in lower pH conditions. The convective velocity is estimated by a 1D model of reactive transport. Two other parameters are studied: the influence of thermal gradient and the influence of interconnected cracks on alteration. A strong retroactive effect of convection, due to thermal gradient, on the alteration kinetic is observed inside the crack. These works lead to a complete alteration experiment of a 163 crack network subject to a thermal gradient. The use of the geochemical software, HYTEC, within the framework of this study shows the potential of the software which is however limited by the kinetics law used. (author)

  2. Développement du projet SETUP (Simulations Expérimentale et Théorique Utiles à la planétologie) : application à l'étude de la physico-chimie de l'atmosphère de Titan

    OpenAIRE

    2010-01-01

    The work of this thesis enters in the frame of the development of a scientific program named S.E.T.U.P. (a french acronym for Theoretical and Experimental Simulations Useful for Planetology) whose objective is to perform representative laboratory simulations of Titan's atmosphere. The study seeks to highlight the mechanisms responsible for the evolution of region of the stratosphere where a neutral chemistry is involved. With this aim, an experimental device has been built. The coupled N2/CH4...

  3. Methodological study of the diffusion of interacting cations through clays. Application: experimental tests and simulation of coupled chemistry-diffusion transport of alkaline ions through a synthetical bentonite; Etude methodologique de la diffusion de cations interagissants dans les argiles. Application: mise en oeuvre experimentale et modelisation du couplage chimie-diffusion d'alcalins dans une bentonite synthetique

    Energy Technology Data Exchange (ETDEWEB)

    Melkior, Th

    2000-07-01

    The subject of this work deals with the project of underground disposal of radioactive wastes in deep geological formations. It concerns the study of the migration of radionuclides through clays. In these materials, the main transport mechanism is assumed to be diffusion under natural conditions. Therefore, some diffusion experiments are conducted. With interacting solutes which present a strong affinity for the material, the duration of these tests will be too long, for the range of concentrations of interest. An alternative is to determine on one hand the geochemical retention properties using batch tests and crushed rock samples and, on the other hand, to deduce the transport parameters from diffusion tests realised with a non-interacting tracer, tritiated water. These data are then used to simulate the migration of the reactive elements with a numerical code which can deal with coupled chemistry-diffusion equations. The validity of this approach is tested by comparing the numerical simulations with the results of diffusion experiments of cations through a clay. The subject is investigated in the case of the diffusion of cesium, lithium and sodium through a compacted sodium bentonite. The diffusion tests are realised with the through-diffusion method. The comparison between the experimental results and the simulations shows that the latter tends to under estimate the propagation of the considered species. The differences could be attributed to surface diffusion and to a decrease of the accessibility to the sites of fixation of the bentonite, from the conditions of clay suspensions in batch tests to the situation of compacted samples. The influence of the experimental apparatus used during the diffusion tests on the results of the measurement has also been tested. It showed that these apparatus have to be taken into consideration when the experimental data are interpreted. A specific model has been therefore developed with the numerical code CASTEM 2000. (author)

  4. Organic chemistry and radiochemistry: study of chemical interactions between iodine and paint of French nuclear reactor in a severe accident situation; Chimie organique et radiochimie. Etude des interactions chimiques iode-peinture dans un reacteur nucleaire (de type R.E.P.) en situation d'accident grave

    Energy Technology Data Exchange (ETDEWEB)

    Aujollet, Y. [Direction Generale de la Surete Nucleaire et de la Radioprotection, 75 - Paris (France)

    2005-01-01

    In Phebus (French in pile facility; PWR scale 1/5000) experiments, performed by the Institut de Radioprotection et de Surete Nucleaire, few quantities of organic iodides were registered after interaction between iodine and reactor containment paint. This study concerns all mechanisms of chemical reactions between iodine and the polymer of the paint in order to estimate the organic iodides released from the paint. At first, all the paint components had been identified. Several models of chemical sites of the polymer were synthesized and tested with iodine in different conditions of temperature and radiation. These experiments showed interactions between iodine and secondary or tertiary amines by charge transfer. In few cases, the complex of tertiary amines creates oxidation reactions. (author)

  5. Synthesis of nano-particles by soft chemistry: structural, morphological and dimensional control. Studies of the electrochemical properties (towards dyes solar cells); Synthese de nanoparticules par chimie douce: controle structural, morphologique et dimensionnel. Etudes des proprietes electrochimiques (vers les cellules solaires a colorants)

    Energy Technology Data Exchange (ETDEWEB)

    Cassaignon, S.; Koelsch, M.; Jolivet, J.P. [Paris-6 Univ. Pierre et Marie Curie, Chimie de la Matiere Condensee de Paris, CNRS UMR 7574, 75 - Paris (France)

    2006-07-01

    In this work are described the electrochemical behaviour of different TiO{sub 2} films (anatase, brookite and rutile) in aqueous solution and the influence of the parameters as the crystal structure and the morphology on the electrochemical answer. To complete this study, the capacity of the double layer has been measured by impedance spectroscopy. Voltage measurements of TiO{sub 2} sensitized by a dye will allow to discuss the reversibility of the system and the rearrangement mechanisms. At last, the influence of the nature of the TiO{sub 2} particles (anatase, rutile and brookite) on the photovoltage has been studied in order to estimate their interest for photovoltaic devices. (O.M.)

  6. Développement d'un modèle de chimie multiphase couplé à un modèle de microphysique quasi-spectral : Application à un événement nuageux échantillonné au Puy de Dôme

    OpenAIRE

    Leriche, Maud

    2000-01-01

    Clouds influence the oxidizing capacity of the troposphere and also, the radiative balance of the planet through the multiphase chemical processes which are still poorly understood. The aim of this work was to improve our understanding of the physico-chemical processes inside clouds. For this purpose, a numerical model of multiphase chemistry has been developed and coupled with a microphysical model (Berry and Reinhardt, 1974) based on the gas phase chemistry model of Madronich and Calvert (1...

  7. Fiche pratique: Anaphores et enchainements; B. d. de Grand Vent; FDM Frequence plus: Une minute sur la mode; Chimie pour non-chimistes (Practical Ideas: Anaphors and Linking; The Comic Strip "Grand Vent"; One Minute on Fashion; Chemistry for Non-Chemists).

    Science.gov (United States)

    Baldovi, Josep Ramon Torres

    1994-01-01

    Ideas for French instruction are offered, including a grammar exercise on pronouns; exploration of a comic strip's language and culture; use of a taped program on fashion; and an activity to help French language teachers cope with unfamiliar discipline-specific texts, whose topics (but not language) are familiar to their students. (MSE)

  8. Chemistry 300. Administration Manual for Supervising Teachers, Provincial Examination, Answer Key--Multiple-Choice and Written-Answer Questions, and Provincial Summary Report = Chimie 300. Guide d'administration a l'intention des surveillants d'examen, Examen provincial, Cle de correction--Questions choix multiple et Questions responses ouvertes, et Rapport sommaire provincial.

    Science.gov (United States)

    Manitoba Dept. of Education and Training, Winnipeg.

    This collection of manuals contains the Manitoba Provincial Chemistry Examination for students seeking credit in Senior 4 Chemistry (Chemistry 300) and instructions for its use and grading. The examination is based on the Core Topics of the Senior 4 Chemistry course and accounts for 30% of the student's final grade in the course. The examination…

  9. Comment exercer l'expertise scientifique avec des savoirs non stabilisés ? aérostats, masque à gaz et lampes : inventions, chimie et demandes administratives et policières dans les années 1780 en France

    OpenAIRE

    Thébaud-Sorger, Marie

    2006-01-01

    I shall address the problem of the expertise of innovations, focusing on inventions which apply then recent discoveries in chemistry, a discipline which was in a period of great transformation. How could a judgement be accurate when knowledge was still forming? Before discussing this problem, I first take as examples some innovations which used the new chemistry of gases: the Argand lamp, the gas mask to drain the cesspools of Pilatre de Rozier and the first aerostatic experiments. Such inven...

  10. Chimie de coordination de radicaux nitronyl-nitroxyde pontants pour l’élaboration de matériaux magnétiques moléculaires : synthèse, structures cristallines, propriétés magnétiques et spectroscopie électronique

    OpenAIRE

    Lannes, Anthony

    2014-01-01

    For the past decades, electronics have been developed in order to meet the increasing need of information storage, always evolving to the constant upgrade of their components: better, faster, smaller. Twenty-five years ago, the recently created field of molecular magnetism allowed designing entities responding to the aforementioned requirements: Single- Molecule-Magnets (SMMs). On the one hand, those are compounds showing magnetic bistability affording to stock information and on the other ha...

  11. Contribution de méthodes de la chimie analytique à l'amélioration de la qualité de fruits et à la détermination de mécanismes (EGE) et de risques d'incendie

    OpenAIRE

    Barboni, Toussaint

    2006-01-01

    This study has two parts; one for analysis of aromas and flavonoids about two fruits and the second is devoted to the study of risk to personnel involved in a wildlandfire. These two themes reflect an expectation level of different actors and are part of different projects which the laboratory is associated.; Cette étude comporte deux parties, la première concerne l'analyse des arômes et des flavonoïdes sur deux fruits insulaires et la deuxième est consacrée à l'étude du risque encouru par le...

  12. Experimental study of chemical-mechanical coupling during percolation of reactive fluid through rocks under stress, in the context of the CO{sub 2} geological sequestration; Etude experimentale du couplage chimie-mecanique lors de la percolation d'un fluide reactif dans des roches sous contrainte, dans le contexte de la sequestration geologique du CO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Le Guen, Y

    2006-10-15

    CO{sub 2} injection into geological repositories will induce chemical and mechanical instabilities. The study of these instabilities is based on experimental deformation of natural rock samples under stress, in the presence of fluids containing, or not, dissolved CO{sub 2}. Triaxial cells used for the experiments permitted an independent control and measurement of stress, temperature, fluid pressure and composition. Vertical strains were measured during several months, with a resolution of 1.10{sup -12} s{sup -1} on the strain rate. Simultaneously, fluids were analysed in order to quantify fluid-rock interactions. For limestone samples, percolation of CO{sub 2}-rich fluids increases strain rate by a factor 1.7 up to 5; on the other hand, sandstone deformation remained almost the same. Increase in strain rate with limestone samples was explained by injected water acidification by the CO{sub 2} which increases rock solubility and reaction kinetics. On the opposite, small effect of CO{sub 2} on quartz explains the absence of deformation. X-ray observations confirmed the importance of rock composition and structure on the porosity evolution. Numerical simulations of rock elastic properties showed increasing shear stress into the sample. Measured deformation showed an evolution of reservoir rocks mechanical properties. It was interpreted as the consequence of pressure solution mechanisms both at grains contacts and on grain free surfaces. (author)

  13. Fiche pratique: Anaphores et enchainements; B. d. de Grand Vent; FDM Frequence plus: Une minute sur la mode; Chimie pour non-chimistes (Practical Ideas: Anaphors and Linking; The Comic Strip "Grand Vent"; One Minute on Fashion; Chemistry for Non-Chemists).

    Science.gov (United States)

    Baldovi, Josep Ramon Torres

    1994-01-01

    Ideas for French instruction are offered, including a grammar exercise on pronouns; exploration of a comic strip's language and culture; use of a taped program on fashion; and an activity to help French language teachers cope with unfamiliar discipline-specific texts, whose topics (but not language) are familiar to their students. (MSE)

  14. TEM characterisation of stress corrosion cracks in nickel based alloys: effect of chromium content and chemistry of environment; Caracterisation par MET de fissures de corrosion sous contrainte d'alliages a base de nickel: influence de la teneur en chrome et de la chimie du milieu

    Energy Technology Data Exchange (ETDEWEB)

    Delabrouille, F

    2004-11-15

    Stress corrosion cracking (SCC) is a damaging mode of alloys used in pressurized water reactors, particularly of nickel based alloys constituting the vapour generator tubes. Cracks appear on both primary and secondary sides of the tubes, and more frequently in locations where the environment is not well defined. SCC sensitivity of nickel based alloys depends of their chromium content, which lead to the replacement of alloy 600 (15 % Cr) by alloy 690 (30 % Cr) but this phenomenon is not yet very well understood. The goal of this thesis is two fold: i) observe the effect of chromium content on corrosion and ii) characterize the effect of environment on the damaging process of GV tubes. For this purpose, one industrial tube and several synthetic alloys - with controlled chromium content - have been studied. Various characterisation techniques were used to study the corrosion products on the surface and within the SCC cracks: SIMS; TEM - FEG: thin foil preparation, HAADF, EELS, EDX. The effect of chromium content and surface preparation on the generalised corrosion was evidenced for synthetic alloys. Moreover, we observed the penetration of oxygen along triple junctions of grain boundaries few micrometers under the free surface. SCC tests show the positive effect of chromium for contents varying from 5 to 30 % wt. Plastic deformation induces a modification of the structure, and thus of the protective character, of the internal chromium rich oxide layer. SCC cracks which developed in different chemical environments were characterised by TEM. The oxides which are formed within the cracks are different from what is observed on the free surface, which reveals a modification of medium and electrochemical conditions in the crack. Finally we were able to evidence some structural characteristics of the corrosion products (in the cracks and on the surface) which turn to be a signature of the chemical environment. (author)

  15. Uncertainty estimation and global forecasting with a chemistry-transport model - application to the numerical simulation of air quality; Estimation de l'incertitude et prevision d'ensemble avec un modele de chimie transport - Application a la simulation numerique de la qualite de l'air

    Energy Technology Data Exchange (ETDEWEB)

    Mallet, V.

    2005-12-15

    The aim of this work is the evaluation of the quality of a chemistry-transport model, not by a classical comparison with observations, but by the estimation of its uncertainties due to the input data, to the model formulation and to the numerical approximations. The study of these 3 sources of uncertainty is carried out with Monte Carlo simulations, with multi-model simulations and with comparisons between numerical schemes, respectively. A high uncertainty is shown for ozone concentrations. To overcome the uncertainty-related limitations, a strategy consists in using the overall forecasting. By combining several models (up to 48) on the basis of past observations, forecasts can be significantly improved. This work has been also the occasion of developing an innovative modeling system, named Polyphemus. (J.S.)

  16. The chemistry of molten salt mixtures: application to the reductive extraction of lanthanides and actinides by a liquid metal; Chimie des melanges de sels fondus. Application a l'extraction reductrice d'actinides et de lanthanides par un metal liquide

    Energy Technology Data Exchange (ETDEWEB)

    Finne, J

    2005-10-15

    The design of a process of An/Ln separation by liquid - liquid extraction can be used for on-line purification of the molten salt in a molten salt nuclear reactor (Generation IV) as well as reprocessing various spent fuels. In order to establish the chemical properties of An and Ln in molten salt mediums, E - pO{sub 2} - diagrams were established for the relevant chemical elements. With the purpose of checking the possibilities of separating the An from Ln, the real activity coefficients in liquid metals were measured. An experimental protocol was developed and validated on the Gd/Ga system. It was then transferred to radioactive environment to measure the activity coefficient of Pu in Ga. The results made it possible to estimate the effectiveness of the Pu extraction and its separation from Gd and Ce. The selectivity was shown to decrease with the temperature and Al and Ga showed a good selectivity between Pu and the Ce in fluoride medium. (author)

  17. Physical chemistry of hydrated molecular sieves: combined study of theoretical and experimental approaches. Understanding and outlooks of hydration mechanism of alumino phosphates; Physico-chimie des tamis moleculaires hydrates: etude combinee experience/theorie. Comprehension et previsions des mecanismes d'hydratation des aluminophosphates

    Energy Technology Data Exchange (ETDEWEB)

    Poulet, G. [Institut universitaire de technologie, 74 - Annecy-le-Vieux (France); Sautet, Ph. [Ecole Nationale Superieure de Lyon, 69 (France); Centre National de la Recherche Scientifique (CNRS), 69 - Villeurbanne (France); Tuel, A. [Institut de Recherches sur le Catalyse, UPR 5401, 69 - Villeurbanne (France)

    2005-01-01

    Microporous alumino-phosphates AlPO{sub 4}-n have drawn considerable attention due to their potential to act as heterogeneous catalysts and molecular sieves. Hydration of these compounds usually modifies the coordination of framework aluminium species and causes a reversible structure deformation. Here, a combined use of experimental tools and of a theoretical approach based on the density functional theory (DFT) contributes to a better knowledge of the interactions between water molecule and AlPO{sub 4}-n frameworks. Information on the behaviour of water in the pores has been obtained from the study of a model compound, AlPO{sub 4}-34. A dehydration/re-hydration mechanism has been proposed as well as a partially hydrated phase, in agreement with solid-state NMR and X-ray diffraction results. Then, a complete experimental study (infrared spectroscopy, X-ray diffraction, thermal analysis, NMR) has been supplemented by static or dynamic theoretical approaches to get information on the calcined re-hydrated AlPO{sub 4}-18 phase. (authors)

  18. Risk assessment of heavy metal pollution in alluvial soils and sediments of the Grote Beek river (Belgium)

    OpenAIRE

    Cappuyns, Valérie; Swennen, Rudy

    2003-01-01

    Consoil 2003 RISK ASSESSMENT OF HEAVY METAL POLLUTION IN ALLUVIAL SOILS AND SEDIMENTS OF THE GROTE BEEK RIVER (BELGIUM) Valérie Cappuyns, Rudy Swennen and Katrien De Nil Katholieke Universiteit Leuven, Fysico-chemische Geologie, Celestijnenlaan 200C, 3001 Heverlee, Belgium Tel. +3216327297, Fax. +3216327981, e-mail: 1. Introduction Wastewater discharge from the processing of phosphate ores has contributed to pollution by heavy metals ...

  19. Reseñas

    OpenAIRE

    Macía, Carlos; Brieva, Jorge A.; Villarroel A., Carlos

    2012-01-01

    K. GARLEFF und H. STINGL (1985). Südamerika. Geomorphologie und Palaoökologie des Jungeren Quartärs. Zentralblatt fur Geologie und Paläontologie Teil I., Jahrgang 1984, Heft 11/12. E. Schweizerbartl sche Verlagsbuchanlung (Nägele U. Obermiller). Stuttgart. 1985. / SCHRIMPFF E. 1984. Pleniglaziale und Rezente Bodendildung auf vulkanishen Ashen und Diabasen in der Zentral - Und Westkordillere Kolumbiens, Zbl. Geol. Palaont., Teil I, 11/ 12. 1555 • 1557. Stuttgart. / ROLSHOVEN, M. 1984. Landscha...

  20. Nuclear warfare

    CERN Multimedia

    Broda

    1981-01-01

    Le Prof.Broda a étudié à Vienne et Berlin et a travaillé pendant la dernière guerre mondiale en Grande Bretagne pour le conseil de la recherche médicale, notamment sur la chimie de la vision. Il est maintenant Prof. de la chimie, physique et radiochimie à l'Université de Vienne, où il concentre ses travaux sur les méchanisme de transport d'énergie à travers les cellules de membranes.

  1. Macromolecules and Enzymes: The Geneva Heritage from Kurt H. Meyer and Edmond H. Fischer.

    Science.gov (United States)

    Fischer, Edmond H; Piguet, Alfred

    2009-12-01

    On the 26th May 2009, Edmond Fischer, winner with Ed Krebs of the Nobel prize in physiology or medicine in 1992, and his colleague at the time of his research activities at the Ecole de chimie of the University of Geneva, Alfred Piguet, met with Andreas Hauser, Claude Piguet and Howard Riezman of the Section de chimie et biochimie of the University of Geneva to talk about how they became scientists under the impetus of Kurt H. Meyer and what became of them thereafter.

  2. Le problème des hydrates dans le contexte de la production et du transport polyphasiques des pétroles bruts et des gaz naturels. Première partie : physico-chimie de la formation et de la dissociation des hydrates Hydrates Problem Within the Framework of Multiphase Production and Transport of Crude Oils and Natural Gases. Part One: Physical-Chemistry of Hydrates Formation and Dissociation

    Directory of Open Access Journals (Sweden)

    Behar E.

    2006-11-01

    Full Text Available L'exploitation en mer des gisements de combustibles fossiles fluides a amplifié le besoin d'accroître nos connaissances sur les hydrates qui sont susceptibles de boucher les installations de production, de traitement et de transport. Dans cette publication, la structure moléculaire des hydrates I, II et H est rappelée, ensuite l'analyse physico-chimique de leur formation est succinctement décrite tant sur les plans thermodynamique que cinétique. Enfin, les remèdes possibles aux problèmes rencontrés par les compagnies opératrices sont indiqués, essentiellement les inhibiteurs thermodynamiques classiques tels que les alcools ou les sels qui diminuent la température de formation des hydrates, et les additifs dispersants qui évitent la croissance et/ou l'agglomération des cristaux. Pour terminer, une boucle pilote de circulation originale est présentée, ses caractéristiques qui permettent la validation des additifs dispersants dans des conditions hydrodynamiques et physico-chimiques représentatives étant soulignées. Offshore exploitation of fossil fluid fuels has emphasized the need of improving our knowledge on hydrates which can plug production, treatment and transport facilities. In this paper, the molecular structure of I, II and H hydrates is recalled, then the physical-chemistry of their formation is briefly reviewed from both the thermodynamic and the kinetic points of view. Finally, the possible remedies to the problems met by operating companies are described, mainly classical thermodynamic inhibitors such as alcohols or salts which decrease the hydrates formation temperature, and dispersant additives which avoid crystals growth and/or agglomeration. At last an original circulation loop at pilot scale is presented, its characteristics which allow the testing of dispersant additives under representative hydrodynamic and physico-chemical conditions being outlined.

  3. Energy Transfer between Post-Transition Elements & Rare Earths in Oxide & Chalcogenide Glasses.

    Science.gov (United States)

    1979-08-27

    Israel. ***Laboratoirc de Chimie Minerale Structurale associ& au CNRS, Faculte des Sciences Phanmaccutiques et Biologiques, 4 avenue de l’Observatoire...Di’part’oznnt de Chime minerale , anlvtique et appliqtue, Unitersity of Geneva, Stt it.-er/and \\Nr)N SPE(TOR Soreq Nu’tclear Re search Center. avne, Israel

  4. Correlation of Lethal Concentrations of Heavy Metals with Tissue Levels of Earthworms

    Science.gov (United States)

    1988-08-01

    pubiS. vd $89 7 t F ~~------~--- -- --- - - _____-- LABORATOIRE DE ZOOBOOLOGIE DU SOL LABORATOIRE DE CHIMIE ANALYTIQUE INRA/CNRS, CEPE Louis Emberger...0) 3JANCRQZM Ng 30JgcXXOR DUJ SOL. ABRIMIRE DE CHIII ANALYTIQUE =*A=$ MX~ip~ w Louis iberte UsfL NPW V333Nf7LIRPac Place Bugi". batailln I ~ ~ 343 UM

  5. 807-IJBCS-Article-Abdoulaye Demba N'diaye

    African Journals Online (AJOL)

    DR GATSING

    1 Laboratoire de Chimie de l'Eau, Institut National de Recherches en Santé Publique de Nouakchott, BP 690, ..... L'eau potable de la ville de Nouakchott est caractérisée par des teneurs en sodium ..... manganese in aqueous systems. Geol.

  6. Ultrasound effects.

    Science.gov (United States)

    Martin, A O

    1985-07-19

    In a listing of the new foreign associates of the National Academy of Sciences (News and Comment, 17 May, p. 826), the name of Pierre Chambon, Biochemistry, Institut de Chimie Biologique, Faculté de Médecine, Strasbourg, France, was inadvertently omitted.

  7. Chemistry for DUMMIES: how to popularize and introduce chemistry to the general public.

    Science.gov (United States)

    Montangero, Marc

    2012-01-01

    To mark the occasion of the International Year of Chemistry, each week in 2011 I posted a two-minute film demonstrating and explaining a simple and safe experiment to be carried out at home using everyday household products on the site www.chimie.ch/nuls.

  8. 1594-IJBCS-Article-Nibie Roger

    African Journals Online (AJOL)

    hp

    1 Laboratoire de Chimie organique et Substances Naturelles, Faculté des Sciences et Techniques ... 3 Laboratoire d'Analyse des Extraits Végétaux et des Arômes (LEXVA Analytique), France. ... feuilles, l'écorce et les fruits de cette plante,.

  9. et du neem (Azadirachta indica A. Juss.)

    African Journals Online (AJOL)

    SARAH

    30 nov. 2015 ... 2Laboratoire de Chimie Organique et de Physique Appliquées ; Université de Ouagadougou ; 03 ... Mots clés : tomate ; ravageurs, extraits végétaux, activité insecticide .... production de tomate: après chaque récolte, les fruits.

  10. Activité antioxydante des extraits méthanoliques de Phragmanthera ...

    African Journals Online (AJOL)

    2014-12-29

    Dec 29, 2014 ... 1Laboratoire de Biologie et Physiologie des Organismes Végétaux, Faculté des Sciences, ... 4Laboratoire de Chimie Organique, École Normale Supérieure, Université de Yaoundé ..... extraits de feuilles, de fruits et de fleurs.

  11. C:\\Users\\AISA\\Desktop\\PDF 26(2)\\KASSI.xps

    African Journals Online (AJOL)

    AISA

    1 Laboratoire de physiologie végétale, UFR Biosciences, Université Félix ... 2Laboratoire de chimie organique et biologique, UFR SSMT, Université Félix ... où elle est à l'origine de la réduction du rendement et de la qualité des fruits. Dans.

  12. 2213-IJBCS-Article-Namory Diop

    African Journals Online (AJOL)

    hp

    Cheikh DIOP1,2*, Maïmouna D. DIARRA1, El Hadji Mamadou SONKO1,4, ... 2Laboratoire de Photochimie et d'Analyses, Département de Chimie, Faculté des ...... performance du filtre lent à sable en ... Xu H, Scherrenberg S M, Van Lier JB.

  13. International Topical Workshop on Advances in Silicon-Based Polymer Science (2nd) Held in Makaha, Oahu, Hawaii on December 16-20, 1990

    Science.gov (United States)

    1990-12-20

    discussed. Laboratoire de Chimie Macromol~culaire associg au CNRS: URA 24. -3- OS14 I Alkyl Substituted Siloxanes: Structure-Performance Relationships as...POLYMERIZATION OF CYCLOSILAZANES -=.ooOoo- E. DUGUET, M. SCHAPPACHER, A. SOUM Laboratoire de Chimnie des Polymires Organiques Universitt Bordeaux 1 351

  14. Report on the International Workshop on Progress towards Molecular Scale Electronics Held in University of Durham on 25-28 March 1990

    Science.gov (United States)

    1990-03-28

    and A. Skoulios Institute de Physique et Chimie des Materiaux de Strasbourg Groupe des Materiaux Organiques , I.C.S. Strasbourg, France R. D. Miller IBM...Groupe Des Matreiaux Organiques , Institut Charles Sadron, 6 rue Boussingault, 67083 Strasbourg Cedex, France. Tel: 3388414000, Fax: 33 88 414099 Dr. A

  15. Second scientific seminar 'Evaluation of mineral resource deposits as a basis for decision making in mining' at the Freiberg Mining Academy on 20 and 21 September 1979

    Energy Technology Data Exchange (ETDEWEB)

    Trillhose, A.

    1980-02-01

    The seminar was held with 140 participants predominantly from Eastern Europe. Twenty two reports were held and discussed. Essential features of selected reports are presented. They include prerequisites for decisions such as information on resources, geological conditions, mining technology applied, evaluation methods and their criteria, the trend to high capacity, process integration and maintenance reduction, and optimization of mine planning and design. Five further report titles dealing with related experiences in brown coal surface mining are given. A selection of seminar proceedings will be published in 'Neue Bergbautechnik' and in 'Zeitschrift fuer angewandte Geologie'. (In German)

  16. DGMK spring meeting of the 'Exploration and Production' department. Authors' manuscripts; DGMK-Fruehjahrstagung des Fachbereichs 'Aufsuchung und Gewinnung'. Autorenmanuskripte

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The spring meeting of the Deutsche Wissenschaftliche Gesellschaft fuer Erdoel, Erdgas und Kohle e.V. focused on exploration and production. Papers were presented on exploration and production in general, geology, deposit development, extraction of petroleum/natural gas, drilling, underground storage, geophysics and geochemistry. [German] Die Fruehjahrstagung der Deutschen Wissenschaftlichen Gesellschaft fuer Erdoel, Erdgas und Kohle e.V. wurde vom Fachbereich ''Aufsuchung und Gewinnung'' bestimmt. Die Vortraege beschaeftigten sich mit den Gebieten Exploration and Production allgemein, Geologie, Lagerstaettentechnik, Foerdertechnik fuer Erdoel/Erdgas, Bohrtechnik, Untertagesspeichertechnik, Geophysik und Geochemie.

  17. 华南某些不同时代花岗岩类岩石中铍地球化学特征的研究

    Institute of Scientific and Technical Information of China (English)

    刘振声

    1975-01-01

    Beryllium was determined from more than 40 granite bodies of different ages in southern China. Results show that it tends to increase with geologie age. The average beryllium contents for granites of various ages are (%): Hsuehfeng Period, 0.00016;Early Caledonian, 0.00034; Late Caledonian, 0.00035 ; Indosinian, 0.00055; Early Yenshanian, 0.00111; Late Yenshanian, 0.00032. The overall average content of beryllium of granite in this area is 0.00052%, 0.00047% and 0.00137% for biotite-granites and two-mica granites respectively. There seems to he a close relationship between Bemineralization and Yenshanian granites.

  18. Canto y plaquitas grabadas del norte de Cáceres (Extremadura, España

    Directory of Open Access Journals (Sweden)

    Soledad CORCHÓN RODRÍGUEZ

    2009-12-01

    Full Text Available RESUMEN: Se presentan cinco documentos mobiliares de gran interés arqueológico, recogidos en superficie en el Valle de Ambroz (Norte de Cáceres. Aunque los trabajos de prospección, en curso, probablemente permitirán precisar su contexto arqueológico inmediato, el estudio preliminar de sus relaciones y paralelismos con otros objetos mobiliares sugiere varias hipótesis interpretativas. Se analiza su vinculación con las tradiciones artísticas del Megalitismo, y también la hipótesis de su relación con contextos de Neolítico pre-megalítico, en el marco de tardías pervivencias de tradiciones enraizadas en el Paleolítico final-Mesolítico.ABSTRACT: Five portable documents of great archeologial interest found on the surface in the Valley of Ambroz (northern Caceres, Spain are presented. Although prospection work now being carried out will probably allow us to know their immediate archeological context more precisely, a preliminary study of their relationships and parallelisms with other portable objects suggests several hypotheses for interpretation. Their link with the artistic traditions of Megalithism is analysed, as well as the hypothesis of their relationship to pre-Megalithic Neolithic settings, within the framework of late remains of traditions rooted in the final Paleolithic-Mesolithic

  19. 1846-IJBCS-Article-Koffi Akpagana

    African Journals Online (AJOL)

    hp

    Diversité des espèces cultivées et contraintes à la production en agriculture maraîchère au Togo ... Lomé, Togo. 2 Laboratoire de Chimie des Eaux, Faculté des Sciences, Université de Lomé, BP 1515, Lomé, Togo. ... satisfaire une demande urbaine de plus en plus croissante ..... Profil du Recyclage des Eaux Usées dans.

  20. Extraction Sans Solvant Assistée par Micro-ondes
    Conception et Application à l'extraction des huiles essentielles

    OpenAIRE

    Lucchesi, Marie-Elisabeth

    2005-01-01

    Solvent-Free Microwave Extraction (SFME) is a new extraction process developed at the Laboratoire de Chimie des Substances Naturelles et des Sciences des Aliments of Université de La Réunion. SFME is a combination of traditional extraction technique and an innovative technology, microwave heating. Indeed, although the cohobation and trapping systems of mixing essential water-oil vapor resemble Hydro-Distillation (HD), microwave heating reduces extraction delays considerably and removes the ne...

  1. Ultrastructure Processing of Advanced Materials.

    Science.gov (United States)

    1992-11-01

    Alachua, Florida Patterson Air Force Base, Ohio BALAVOINE, G. A. AEGERTER, M. A. lnstitut de Chimie Moleculaire Instituto de Fisica e Quimica de...Jersey Department of Chemistry, QueenMary College, London, United CHARIIOUILLOT, Y.Kingdom Instituto de Fisica e Quimica deSao Carlos, University of...Center and Department of Physics, DE GODOY, L. H. University of Arizona, Tucson,DE Gooy, . H.Arizona Instituto de Fisica e Quimica de Sao Carlos

  2. Etude de nouveaux oxyhydroxydes de cobalt pouvant être utilisés comme additif conducteur électronique ajoutés à l'hydroxyde de nickel dans les accumulateurs nickel/cadmium et nickel/métal hydrure

    OpenAIRE

    1998-01-01

    Nickel hydroxide is the active material of the positive electrode of alkaline batteries. This material exhibits very good electrochemical properties but its electronic conductivity is very low. To optimize the electrode properties, all battery manufacturers use cobalt which are claimed to be under the CoOOH from.A general study of cobalt oxyhydroxides has been undertaken. These materials have been obtained by precipitation and by "chimie douce" reactions. The structure of these cobalt oxyhydr...

  3. Sol-Gel Optics: Proceedings SPIE-The International Society for Optical Engineering Held in San Diego, California on 11-13 July 1990. Volume 1328

    Science.gov (United States)

    1992-03-01

    Physicochimie des Materiaux "CNRS (France); G. Le Flem, C. Parent. Lab. de Chimie du Solide’CNRS (France); C. L. Lurin, Kodak Pathe (France...Time Process Result 1 25C Mixing Produces colloidalə Hr Hydrolysis & Condensation) suspension (sol) Used for films, coatings 2 250CCsi Sol cast...metal-organic derived oxide coatings. 2. INTRODUCTION Sol-gel derived oxide films may be deposited either from colloidal suspensions or clear polymer

  4. Polypyrrole Stability and Coatings for Radar Absorbing Materials

    Science.gov (United States)

    2004-12-01

    organiques . Dans cet article, on examine la chimie du polypyrrole électro-conducteur et les facteurs relatifs à la préparation de revêtements faits à partir...l’absorbeur. Les absorbeurs faits de matériaux organiques tels que des polymères conducteurs sont légers et présentent des propriétés qu’il est possible de

  5. French chemists and the international reorganisation of chemistry after World War I.

    Science.gov (United States)

    Fauque, Danielle M E

    2011-07-01

    Founded in 1919, the International Union of Pure and Applied Chemistry (IUPAC) was successor to the International Association of Chemical Societies (IACS), which had been founded eight years earlier at the initiative of Albin Haller. The statutes of the IUPAC (like those of the IACS) were written in French, and it was agreed that the IUPAC's administrative headquarters should be in Paris. With these arrangements in place, the role of French chemists generally, and of Haller and Charles Moureu in particular, assumed crucial importance. In 1927, on the occasion of the centenary of Marcelin Berthelot's birth, plans were laid for an international centre for chemistry in Paris, soon to be known as the Maison de la Chimie. From the start, the Maison de la Chimie project was led by the French, most conspicuously by Jean Gérard, general secretary of the Société de chimie industrielle and of the IUPAC. Gérard's contribution to a number of national and international committees, notably for scientific documentation, left an enduring legacy. The years between 1918 and 1927, especially 1918-1919, were decisive for the rebuilding, on many fronts, of international networks embracing individuals and institutions recently separated by war. This article examines the particular case of chemistry, with reference to this wider context and to the widely shared determination to fashion an organisation that would transcend national boundaries and embrace both the pure and the applied aspects of the discipline.

  6. Zur Geschichte der Geowissenschaften im Museum für Naturkunde zu Berlin. Teil 6: Geschichte des Geologisch-Paläontologischen Instituts und Museums der Universität Berlin 1910–2004

    Directory of Open Access Journals (Sweden)

    W. Gross

    2004-01-01

    Full Text Available Die Entwicklung des Geologisch-Paläontologischen Instituts und Museums der Universität Berlin von einer Institution, die Geologie zusammen mit Paläontologie als eine Einheit vertrat, über eine Institution, die eine geotektonische Ausrichtung hatte, zu einer auf Paläontologie konzentrierten Institution wird nachvollzogen. Die beiden Institutsdirektoren am Anfang des 20sten Jahrhunderts waren Vertreter der allumfassenden Geologie des 19ten Jahrhunderts, während die beiden folgenden Direktoren eine Geologie ohne Paläontologie vertraten. Das führte zu einer Trennung der beiden Richtungen, und nach der III. Hochschulreform der DDR 1968 verblieb allein die sammlungsbezogene Paläontologie am Museum. Nach der Wiedervereinigung wurde ein Institut für Paläontologie mit biologischer Ausrichtung mit zwei Professuren, einer für Paläozoologie und einer für Paläobotanik, eingerichtet. The development of the Geologisch-Paläontologisches Institut und Museum of the Museum für Naturkunde at the Humboldt University (formerly Friedrich-Wilhelm-Universität in Berlin from a geology-paleontology institution to a pure paleontology institution is described. The first two directors of the department in the beginning of the 20th century, Prof, von Branca and Prof. Pompeckj, represented a 19th century concept of a geology, which included paleontology, even vertebrate paleontology as the crown jewel of geology. They fought sometimes vigorously against a separation of paleontology from geology. The next two directors. Prof. Stille and Prof, von Bubnoff, were the leading geologists in Germany; to be a student of Stille was a special trade mark in geology of Germany. They represented a geology centered on tectonics. The separation of paleontology as separate section was prepared. The destructions of the Second World War, the following restaurations and the division of Germany into two States influenced strongly their directorships. The education of geologists

  7. Assessment of the potential of the Mainfranken region, northern Bavaria, for underground storage of geothermal energy; Erkundung des regionalen Potentials fuer die Untergrundspeicherung thermischer Energie in Mainfranken (UTEM)

    Energy Technology Data Exchange (ETDEWEB)

    Barthel, R.; Heinrichs, G.; Udluft, P. [Lehr- und Forschungsbereich Hydrogeologie und Umwelt, Inst. fuer Geologie, Univ. Wuerzburg (Germany); Ebert, H.P.; Fricke, J. [Abt. Waermedaemmung/Waermetransport, Bayerisches Zentrum fuer Angewandte Energieforschung e.V., Wuerzburg (Germany)

    1997-12-01

    The following paper presents a research project that is planned as a cooperation of the Geological Institute, University of Wuerzburg and the Bavarian Center of Applied Energy Research. In this project the potentials for underground thermal energy storage will be investigated in the region of Mainfranken, Northern Bavaria (Main = the river `Main`, Franken = Franconia). All aspects of underground storage will be studied with respect to the specific geographical and geological situation of the area. The study will provide a detailed map of possible storage sites, from which several case studies and at least one demonstration projects will result. (orig.) [Deutsch] Im vorliegenden Beitrag wird ein Forschungsprojekt vorgestellt, das gemeinsam vom Institut fuer Geologie der Universitaet Wuerzburg und dem Zentrum fuer Angewandte Energieforschung in Bayern geplant wird. Ziel des Projekts ist die Erkundung des Potentials fuer die Untergrundspeicherung thermischer Energie in Mainfranken (Nordbayern). Alle Aspekte der Untergrundspeicherung werden regionalspezifisch betrachtet. Neben der Erstellung differenzierter Karten geeigneter Standorte sind Fallstudien und Demonstrationsprojekte in Planung. (orig.)

  8. Bibliografía

    Directory of Open Access Journals (Sweden)

    Martí Mas Cornellá

    1992-01-01

    Full Text Available RESEÑA 1 de : Thoen, Hugo; Burgeois, Jean; Vermeulen, Frank; Crombé, Philippe; Verlaeckt, Koen. Studia Archaeologica, Líber amicorum Jacques A. E. Nenquin. Gante : Universiteit Gent, Seminaria voor Archeologie, 1991. RESEÑA 2 de : Hodder, Ian; Orton, Clive. Análisis Espacial en Arqueología. Barcelona : Editorial Critica, 1990. RESEÑA 3 de : Barriere, Claude. L'Art parietal du Ker de Massat. Toulouse : Presses Universitaires du Mirail, 1990. RESEÑA 4 de : Ramos Muñoz, José; Espejo Herrerías, Mª del Mar y otros. Cueva de Árdales. Su recuperación y estudio. Árdales : Ayuntamiento de la Villa de Árdales, 1992. RESEÑA 5 de : Guilaine, Jean; Gutherz, Xavier. Autour de Jean Arnal. Montpellier : Université des Sciences et Techniques du Languedoc, 1990. RESEÑA 6 de : González Echegaray, Joaquín. El Creciente fértil y la Biblia. Estella (Navarra : Ed. Verbo Divino, 1991. RESEÑA 7 de : de Góngora y Iviartínez, Manuel. Antigüedades prehistóricas de Andalucía. Estudio preliminar por iVIauricio Pastor Muñoz y Juan Antonio Pachón Romero. Granada : Universidad de Granada, 1991. RESEÑA 8 de : Bonnet, Charles. Kerma royaume de Nubie. Ginebra : Mission archéologique de l'Université de Genéve au Soudan, 1990.

  9. De la recherche des principes des mixtes naturels chez Du Clos

    Directory of Open Access Journals (Sweden)

    Rémi Franckowiak

    2012-03-01

    Full Text Available Samuel Cottereau Du Clos (1598–1685 paraît être le premier Français à marier dans une chimie, pour lui science des substances, physique des qualités, une démonstration légale – suivant les lois du mouvement – et une démonstration causale – suivant les interprétations principielles –, en ramenant les phénomènes naturels à deux ordres de raisons différents et complémentaires. Les considérations mécanistes représentent pour lui une première approche, une étape vers la connaissance de la « vérité des choses » en chimie. Cette proposition originale qui vise à introduire en chimie des considérations mécanistes tout en conservant les explications principielles est développée au sein de l’ancienne Académie des Sciences, en particulier à travers sa critique de 1668/1669 des Certain Physiological Essays de Boyle.Samuel Cottereau Du Clos (1598–1685 appears as the first French chemist to combine in chemistry (for him, the science of substances, the physics of qualities demonstrations using the laws of motion with demonstrations using the qualities of chemical principles. In this way, he brought to bear two different and complementary orders of explanation. According to Du Clos, the mechanical considerations represent a first approach, a stage towards the knowledge of “the truth of things” (la vérité des choses in natural philosophy. He set out his chemistry at the Académie royale des sciences de Paris, especially through his criticism of Boyle’s Certain Physiological Essays in 1668–1669.

  10. Informations sur le projet Changement d’ Utilisation et de Couverture des Sols

    Directory of Open Access Journals (Sweden)

    Alain Podaire

    2000-05-01

    Full Text Available La communauté travaillant sur les changements de l’environnement global accorde une importance croissante aux modifications d’occupation et d’utilisation des sols et la nécessité d’une approche multidisciplinaire de ce sujet. En effet, ces changements ont un impact significatif sur les intéractions surface terrestre - atmosphère (biogéochimie, chimie de l’atmosphère, eau et énergie, la biodiversité (structure et fonctionnement des écosystèmes, diversité des espèces, fragmentation de la couv...

  11. Énergies

    OpenAIRE

    Albe, Virginie; Bächtold, Manuel; Buty, Christian; Cross, David; Fontanieu, Valérie; Grangeat, Michel; Guedj, Muriel; Hage, Suzane El; Hebel, Florence Le; Hervé, Nicolas; Lerouge, Alain; Mayrargue, Arnaud; Montpied, Pascale; Morge, Ludovic; Munier, Valérie

    2015-01-01

    L’énergie est un thème mobilisé en biologie, en chimie, en géologie, en physique et en technologie. En outre, l’énergie intéresse également les champs investis par les questions socialement vives (la consommation et les économies d’énergie, etc.) ainsi que les domaines de l’éducation à la santé (avec les notions de calories, d’effort physique, de bilan, etc.), au développement durable (ressource énergétique, réchauffement climatique, énergie renouvelable ou non-renouvelable, etc.). Cependant,...

  12. Développement d'un réacteur intensifié en Carbure de Silicium pour la transposition en continu de réactions d'hydrosilylation

    OpenAIRE

    Fustier, Céline

    2012-01-01

    De nos jours, les limites du réacteur batch, outil conventionnel de l'industrie de la chimie fine, en termes de transfert thermique et de transfert de matière, conduisent à envisager le passage en continu de réactions dont les problématiques d'exothermie et de rapidité rendent leur industrialisation difficile. Les réacteurs-échangeurs compacts sont un exemple de technologies intensifiées continues alliant les performances d'un échangeur de chaleur couplées à un bon mélange ainsi qu'à un compo...

  13. Contributions à l'étude de l'origine et de l'évolution de la matière organique dans le Système solaire

    OpenAIRE

    Dobrijevic, M.

    2008-01-01

    Comment la vie est-elle apparue sur la Terre ? Quelle chimie prébiotique1 a permis l'émergence d'une biochimie sur la Terre ? Des processus identiques ont-ils été, ou sont-ils encore, à l'oeuvreailleurs dans le Système solaire ? D'autres voies sont-elles possibles dans des environnements différents de ceux de la Terre primitive ? Quel est le degré de complexité chimique atteint dansles différents environnements planétaires du Système solaire ?Ces questions fondamentales servent de moteur à l'...

  14. Bibliography of Soviet Laser Developments Number 53, May-June 1981.

    Science.gov (United States)

    1982-07-20

    Gheorghe Gheorghiu-Dej Bucuresti. Seria chimie- metalurgie , no. 2, 1980, 21-28. (RZhF, 5/81, 5G272) 100. Kalugin, M.M., Ye.N. Kuz’minova, and S.Ye...spectral lines in ytterbium atoms by electron collisions. OiS, v. 50, no. 6, 1981, 1037-1045. 105. State prizes in 1980 for physics and astronomy...KE, no. 6, 1981, 1319-1321. 124. Rusanov, V.D., A.A. Fridman, and G.V. Sholin (23). Physics of a chemically active plasma with nonequilibrium

  15. Bioraffinerie and Knowledge Based BioEconomy

    OpenAIRE

    2016-01-01

    La question de la transition vers un paradigme de l′usage des ressources renouvelables se traduit par des efforts particuliers de mobilisation de la recherche ; cette mobilisation se déploie dans des domaines divers (énergie solaire, éolienne, substituts du carbone fossile par du carbone renouvelable en énergie, production de carburants liquides et chimie). La volonté de substitution liée à cet effort de production de carbone renouvelable conduit à s′intéresser au domaine spécifique de la bio...

  16. Chapitre 13. L’impact macro-économique du narcotrafic en Colombie

    OpenAIRE

    2014-01-01

    Note portant sur l’auteur Un regard sur la carte du continent latino-américain permet de comprendre pourquoi la Colombie est au carrefour des routes de la cocaïne : elle est équidistante des champs de coca du Pérou et de Bolivie, et des plages de Floride. Son relatif développement industriel et commercial a permis aux institutions et aux individus d’acquérir les compétences requises, concernant la chimie du raffinage, les circuits de financement, et l’organisation du transport de la drogue. A...

  17. Advanced Non-Intrusive Instrumentation for Propulsion Engines

    Science.gov (United States)

    1998-05-01

    fraction rotationnelle fr dans l’etat rotationnel J" [20] : f,(T,J")=FGH(J").(2J"+l) -7 e VT !e VT :(l-ev ) avec : J", niveau quantique ...rotationnel de la raie d’absorption v, niveau quantique vibrationnel de la raie d’absorption FGH(J"), constante caracterisant la structure...Molecular spectroscopy 116, 71-100, 1986. [23] P. Pascal., Nouveau trait6 de chimie minerale, "Proprietds physiques de l’iode", p 456 ä 465, Edition

  18. Fractal-like kinetics, a possible link between preconditioning and sepsis immunodepression. On the chemical basis of innate immunity.

    Science.gov (United States)

    Vasilescu, C; Olteanu, M; Flondor, P

    2012-01-01

    In a recent paper the authors hypothesized that the so called fractal-like enzyme kinetics of intracellular reactions may explain the preconditioning effect in biology (Vasilescu C, Olteanu M, Flondor P, Revue Roumaine de Chimie. 2011; 56(7): 751-7). Inside cells the reaction kinetics is very well described by fractal-like kinetics. In the present work some clinical implications of this model are analyzed. Endotoxin tolerance is a particular case of preconditioning and shows similarities with the immunodepression seen in some sepsis patients. This idea offers a theoretical support for modulation of the enzymatic activity of the cell by changing the fractal dimension of the cytoskeleton.

  19. Elimination du cadmium de l'acide phosphorique par électrodialyse

    African Journals Online (AJOL)

    Département de chimie, université Badji Mokhtar Annaba. Revisé le 14/12/2011. Accepté le 09/01/2012. صﺧﻟﻣ. تﺳﻣﻟا روطﺗﻟا لﺟأ نﻣ مھﻷا ﻲﺳﺎﯾﺳﻟاو يدﺎﺻﺗﻗﻻا نﺎھرﻟا تﺣﺑﺻأ دﻘﻟ ...

  20. Synthesis and Characterization of Layered Double Hydroxides Containing Optically Active Transition Metal Ion

    Science.gov (United States)

    Tyagi, S. B.; Kharkwal, Aneeta; Nitu; Kharkwal, Mamta; Sharma, Raghunandan

    2017-01-01

    The acetate intercalated layered double hydroxides of Zn and Mn, have been synthesized by chimie douce method. The materials were characterized by XRD, TGA, CHN, IR, XPS, SEM-EDX and UV-visible spectroscopy. The photoluminescence properties was also studied. The optical properties of layered hydroxides are active transition metal ion dependent, particularly d1-10 system plays an important role. Simultaneously the role of host - guest orientation has been considered the basis of photoluminescence. Acetate ion can be exchanged with iodide and sulphate ions. The decomposed product resulted the pure phase Mn doped zinc oxide are also reported.

  1. International Conference on Electronic Processes in Organic Materials (6th) Held in Gurzuf, Crimea, Ukraine, on September 25-29, 2006

    Science.gov (United States)

    2006-09-29

    RUBRENE AND TETRACENE Oleksiy Kapitanchuk"𔃼, Alexandr Marchenko1 , Denis Fichoul CEA-Saclay, LRC Nanostructures et Semi-Conducteurs Organiques CNRS-CEA...system. [1] G.Calzaferri, S.Huber, H.Maas, C.Minkowski, Angew.ChemInt.Ed. 2003, 42, 3732-3758 [2] G.Calzaferri, et al. C. R., Chimie 8 (2005) This work...SOLID INTERFACE A. Marchenko, L. Piot, A. Nion, A. Popoff and D. Fichou CEA-Saclay, LRC Nanostnrctures et Semi-Conducteurs Organiques , CNRS-CEA- UPMC

  2. First International Conference on Organic Nonlinear Optics. Section B: Nonlinear Optics, Principles, Materials, Phenomena, and Devices.

    Science.gov (United States)

    1994-01-01

    LEDOUX3 and J. ZYSS 3 1 Chimie des Interactions Mol6culaires (UPR 285 of the CNRS), Collbge de France, 11 Place Marcelin Berthelot, 75005 Paris, France...CHARRAa, N. PFEFFER’, T. P. NGUYENb and V. H. TRAN’ aLeti (CEA-Technologies Avanc6es), DEIN-SPE, Groupe Composants Organiques , Centre d’Etudes de Saclay...Institut des Mat6riaux, 2 rue de la Houssini~re, F44072 Nantes cedex 03, France cLaboratoire des Mat6riaux Organiques c Propri6t6s Sp6cifiques, UPR-CNRS

  3. Bio-energies. The domestic use of wood fuel: the weight of discretion. The urban and industrial wood heating, a growth value. Biomass - electricity - heat, towards a new concept. Bio-gas, a fermenting stake. Bio-components for fuels, foresight and quality. Biomolecules: towards a chemistry of substitution. Wood materials: a concentrate of environment; Les bioenergies. L'usage domestique du bois energie: le poids de la discretion. Le chauffage urbain et industriel au bois, une valeur de croissance. Biomasse - electricite - chaleur, vers un nouveau concept. Le biogaz, un enjeu qui fermente. Biocomposants pour carburants, prevoyance et qualite. Les biomolecules: vers une chimie de substitution. Le bois materiau: un concentre d'environnement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    This dossier presents a status of todays situation of the use of bio-energies in France and of its perspectives of development at the year 2006 vista. Seven aspects of bio-energies are considered: wood fuel, district and industrial heating, biomass production and gasification processes, biogas (methane) production from municipal waste tips, bio-fuels and bio-additives (bio-ethanol, ETBE, colza derived oils, vegetal oil methyl esters), bio-molecules production and valorization as substitutes to petroleum products (lubricants, wetting agents, solvents, polymers, coatings), development of wood materials (environmental advantages: CO{sub 2} immobilization, lower energy needs during fabrication, possible energy valorization at end life). (J.S.)

  4. Les Affinités électives de Goethe : entre science et littérature

    Directory of Open Access Journals (Sweden)

    Bernard Joly

    2011-03-01

    Full Text Available Par leur titre même, Les affinités électives de Goethe renvoient à la doctrine chimique des rapports entre différents corps qui, à partir des travaux d’Etienne-François Geoffroy en 1718, s’impose comme théorie dominante dans la chimie du XVIIIe siècle. Goethe ne se contente pas d’une simple analogie entre les attirances amoureuses qui font et défont les couples et les opérations chimiques qui règlent les liaisons et les précipitations des substances chimiques. Son excellente connaissance de la tradition chimique et alchimique le conduit à considérer l’affinité comme une loi de la nature produisant aussi bien ses effets en chimie que chez les êtres vivants et dans le psychisme.The title of Goethe’s novel Elective Affinities refer to the chemical tenet of rapports between different bodies which, from Etienne-François Geoffroy’s works in 1718, emerge as a prevailing theory in the eighteenth-century chemistry. Goethe does not limit his views to the analogy between love attractions which made and break up couples and chimical processes which determine bonds and precipitations of chemical substances. His excellent knowledge of chemical and alchemical tradition leads him to consider affinity as a law of nature having effects in chemistry as well as in living being and into mind.

  5. Marie Curie, les femmes et la science, d'hier à aujourd'hui

    CERN Document Server

    CERN. Geneva; Mariotti, Chiara; Vicinanza, Domenico

    2017-01-01

    Marie Curie, les femmes et la science, d'hier à aujourd'hui Conférence par Hélène Langevin-Joliot Avec la participation de l'Echo du Reculet de Thoiry. L'enregistrement et la liste d'attente sont déjà complets... Mais il n'est pas rare que des personnes réservent et ne viennent pas. Nous réassignerons les places libérées selon la règle "premier arrivé, premier inscrit". Au vu de la forte demande, la conférence sera également disponible en vidéoconférence : lien d'accès "webcast" disponible en bas de cette page. Hélène Langevin-Joliot, directrice de recherche émérite en physique nucléaire fondamentale au CNRS à Orsay, est aussi la fille de Frédéric et Irène Joliot-Curie (prix Nobel de chimie en 1935) et la petite-fille de Pierre Curie (prix Nobel de physique en 1903) et de Marie Curie (prix Nobel de physique en 1903 et prix Nobel de chimie en 1911). Hélène Langevin-Joliot nous parlera de sa vie scientifique, de l’histoire extraordinai...

  6. Marie Curie, les femmes et la science, d'hier à aujourd'hui - English

    CERN Document Server

    CERN. Geneva

    2017-01-01

    Marie Curie, les femmes et la science, d'hier à aujourd'hui Conférence par Hélène Langevin-Joliot Avec la participation de l'Echo du Reculet de Thoiry. L'enregistrement et la liste d'attente sont déjà complets... Mais il n'est pas rare que des personnes réservent et ne viennent pas. Nous réassignerons les places libérées selon la règle "premier arrivé, premier inscrit". Nous envisageons la possibilité de faire un webcast de la conférence. Plus d'information bientôt. Hélène Langevin-Joliot, directrice de recherche émérite en physique nucléaire fondamentale au CNRS à Orsay, est aussi la fille de Frédéric et Irène Joliot-Curie (prix Nobel de chimie en 1935) et la petite-fille de Pierre Curie (prix Nobel de physique en 1903) et de Marie Curie (prix Nobel de physique en 1903 et prix Nobel de chimie en 1911). Hélène Langevin-Joliot nous parlera de sa vie scientifique, de l’histoire extraordinaire de sa famille et en particulier du rôle des ...

  7. Synthesis and characterization of sodium vanadium oxide gels: the effects of water (n) and sodium (x) content on the electrochemistry of Na(x)V2O5·nH2O.

    Science.gov (United States)

    Lee, Chia-Ying; Marschilok, Amy C; Subramanian, Aditya; Takeuchi, Kenneth J; Takeuchi, Esther S

    2011-10-28

    Sodium vanadium oxide gels, Na(x)V(2)O(5)·nH(2)O, of varying sodium content (0.12 n > 0.01) and interlayer spacing were found to be inversely proportional to the sodium level (x), thus control of sodium (x) content provided a direct, chimie douce approach for control of hydration level (n) and interlayer spacing, without the need for high temperature treatment to affect dehydration. Notably, the use of high temperatures to modify hydration levels can result in crystallization and collapse of the interlayer structure, highlighting the distinct advantage of our novel chimie douce synthesis strategy. Subsequent to synthesis and characterization, results from an electrochemical study of a series of Na(x)V(2)O(5)·nH(2)O samples highlight the significant impact of interlayer water on delivered capacity of the layered materials. Specifically, the sodium vanadium oxide gels with higher sodium content and lower water content provided higher capacities in lithium based cells, where capacity delivered to 2.0 V under C/20 discharge ranged from 170 mAh/g for Na(0.12)V(2)O(5)·0.23H(2)O to 300 mAh/g for Na(0.32)V(2)O(5)·0.01H(2)O. The capacity differences were maintained as the cells were cycled.

  8. Influence of surface charge on the potential toxicity of PLGA nanoparticles towards Calu-3 cells

    Directory of Open Access Journals (Sweden)

    Mura S

    2011-10-01

    Full Text Available Simona Mura1,2, Herve Hillaireau1,2, Julien Nicolas1,2, Benjamin Le Droumaguet1,2, Claire Gueutin1,2, Sandrine Zanna3, Nicolas Tsapis1,2, Elias Fattal1,2 1Univ Paris-Sud, UMR 8612, Châtenay Malabry, F-92296; 2CNRS, Châtenay Malabry, F-92296; 3Laboratoire de Physico-Chimie des Surfaces, CNRS-ENSCP (UMR 7045, Ecole Nationale Superiore de Chimie de Paris, France Background: Because of the described hazards related to inhalation of manufactured nanoparticles, we investigated the lung toxicity of biodegradable poly (lactide-co-glycolide (PLGA nanoparticles displaying various surface properties on human bronchial Calu-3 cells. Methods: Positively and negatively charged as well as neutral nanoparticles were tailored by coating their surface with chitosan, Poloxamer, or poly (vinyl alcohol, respectively. Nanoparticles were characterized in terms of size, zeta potential, and surface chemical composition, confirming modifications provided by hydrophilic polymers. Results: Although nanoparticle internalization by lung cells was clearly demonstrated, the cytotoxicity of the nanoparticles was very limited, with an absence of inflammatory response, regardless of the surface properties of the PLGA nanoparticles. Conclusion: These in vitro results highlight the safety of biodegradable PLGA nanoparticles in the bronchial epithelium and provide initial data on their potential effects and the risks associated with their use as nanomedicines. Keywords: nanoparticles, PLGA, surface properties, Calu-3, toxicity, inflammation

  9. Lavoisier e a sistematização da nomenclatura química

    Directory of Open Access Journals (Sweden)

    Regina Simplício Carvalho

    2012-01-01

    Full Text Available Lavoisier sistematizou a nomenclatura química com base na Lógica de Condillac, e ambos os autores foram inspirados por John Locke. Atacou persistentemente a teoria flogística até a sua derrocada e conseguiu a adesão de vários cientistas a sua teoria do oxigênio. O uso da nova nomenclatura química implicava a aceitação dessa última teoria. Escreveu várias obras, entre elas Méthode de nomenclature chimique e Traité élémentaire de chimie, nas quais divulgou a nova nomenclatura química por toda a Europa. Assumindo que a ciência é um produto cultural, tecemos considerações a luz do pensamento de Thomas Kuhn e Ludwik Fleck.Lavoisier's chemical nomenclature was systematized based on the Logic of Condillac, and both authors were inspired by John Locke. Lavoisier persistently attacked the phlogiston theory until its demise, and he succeeded in getting the support of several scientists to his oxygen theory. The use of the new chemical nomenclature implied acceptance of that theory. He wrote several works, including Methode de nomenclature chimique and Traité élémentaire de chimie, which spread the new chemical nomenclature throughout Europe. Assuming that science is a cultural product, we present a discussion in light of the works of Ludwik Fleck and Thomas Kuhn.

  10. Internet Based Open Access Crystallographic Databases

    Science.gov (United States)

    Upreti, Girish; Seipel, Bjoern; Harvey, Morgan; Garrick, Will; Moeck, Peter

    2006-05-01

    Two freely accessible crystallographic databases are discussed: the Crystallographic Open Database (COD, http://crystallography.net) which contains over 37,000 crystal structures, and the Nano-Crystallography Database (NCD, http://nanocrystallography.research.pdx.edu) which we recently started to support image-based nanocrystallography and (nano) materials science education. Both databases collect crystallographic relevant information in a standardized format; the Crystallographic Information File (CIF). CIF is the standard file format adopted by the International Union of Crystallography (http://iucr.org) for the archiving and distribution of crystallographic information. A subset of the COD, the Predicted Crystallographic Online Database, allows for 3D structural displays of structural polyhedra and wireframes of approximately 2,600 entries. Since electron microscopist are interested in simple, yet technologically important materials, the crystallographic information for those materials will be included in our database. At our NCD site, entries in the COD and the NCD can be visualized in three dimensions (3D) along with (2D) lattice fringe fingerprints plots. The latter supports the identification of unknown nanocrystal phases from high-resolution transmission electron microscopy (HRTEM) images. Morphological crystal information from the database ``Bestimmungstabellen f"ur Kristalle/ ???????????? ??????????,'' (A.K. Boldyrew and W.W. Doliwo-Dobrowolsky, Zentrales Wissenschaftlichers Institute der Geologie und Sch"urfung, Leningrad/ Moscow, 1937/1939) will also be included in the NCD to support image-based nanocrystallography in 3D.

  11. 3D modelling of salt tectonics with a brittle overburden in an extensional regime

    Science.gov (United States)

    Eichheimer, Philipp; Reuber, Georg; Kaus, Boris

    2016-04-01

    Most previous numerical models of salt tectonics only considered 2D cases or did not taken a brittle sedimentary overburden into account, both of which are likely to be important in nature. To get insights into the dynamics of diapiric rise of salt we here present time-dependent high resolution 3D models of salt tectonics in the presence of a brittle overburden and sedimentation. We focus on the internal deformation of an embedded anhydrite layer within a nonlinear viscous salt layer. As salt in nature tends to rise upwards to the surface along fault zones, the salt layer is overlain by a brittle overburden to simulate faulting. The resulting complex folding of the anhydrite layer obtained in our models is consistent with natural observations, e.g. Gorleben [1]. Regarding field examples we vary the shape of the anhydrite layer to understand different modes of deformation [2]. We test the effect of overburden rheology, extension and sedimentation rates on the 3D salt dome patterns and on its internal deformation. [1] O. Bornemann. Zur Geologie des Salzstocks Gorleben nach den Bohrergebnissen. Bundesamt für Strahlenschutz (1991). [2] Z. Chemia, H. Koyi, and H. Schmeling. Numerical modelling of rise and fall of a dense layer in salt diapirs. Geophysical Journal International 172.2 (2008): 798-816.

  12. Application of paper chromatography to the determination of some elements in minerals and rocks; Application de la chromatographie sur papier a la determination de certains elements dans les mineraux et les roches

    Energy Technology Data Exchange (ETDEWEB)

    Agrinier, H. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1964-11-01

    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) [French] 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)

  13. Academic Training: Climate change and challenges for the environment

    CERN Multimedia

    Françoise Benz

    2005-01-01

    2005-2006 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 14, 15, 16 November from 11:00 to 12:00 - TH Auditorium, bldg. 4 Climate change and challenges for the environment by C. Schlüchter / Institut für Geologie, Univ. Bern, CH Climate change as seen by a geologist Glaciers are an integrated part of the high altitudes and the high latitudes of our planet. They are sensitive to temperature and moisture changes and adjust their mass balances accordingly. By doing so they interact with their substratum, the geological basement and they produce characteristic imprints of their presence, their variability and their disappearance. In glacial geology and paleoglaciology such imprints of former glaciers are carefully recorded, mapped and, hopefully, dated in order to obtain amplitude and periodicity records of their changes - as forced by changing climate, as we believe. In the upcoming lectures three aspects will be discussed: the last glaciation in the Swiss Alps. A reconstruction is shown based on fieldwor...

  14. Synthèse, mise en forme et frittage de céramiques thermoélectriques de formulation In2-xGexO3

    OpenAIRE

    Combe, Emmanuel

    2011-01-01

    Ce travail de thèse porte sur l’étude des relations procédé, micro/nanostructures et propriétés thermoélectriques de composés oxydes de formulation In2-xGexO3. Dans ce contexte, des techniques de synthèse des poudres par chimie douce (procédé citrate), de mise en forme en milieu liquide (coulage en moule poreux) et de frittage non conventionnel des céramiques (frittage micro-ondes) ont été développées. Par comparaison à des procédés d’élaboration classiques, le développement du procédé cit...

  15. Contribution à l'étude de la structure et des propriétés des laques de garance

    OpenAIRE

    Sanyova, Jana

    2001-01-01

    Les laques de garance, les pigments artistiques dont les procédés de fabrication étaient souvent des secrets jalousement gardés, ont depuis longtemps éveillé l'intérêt des chimistes. Le premier mode opératoire de laque de garance décrit scientifiquement est dû à Marggrave en 1754, chimiste allemand célèbre surtout pour la découverte du sucre de betterave. L'élucidation de la structure chimique de l'alizarine par Graebe en 1868 est une des étapes fondatrices de la chimie organique. Il a ensuit...

  16. Les savants genevois dans l'Europe intellectuelle du XVIIe au milieu du XIXe siècle

    CERN Document Server

    1987-01-01

    Après une introduction sur l'essor de la science genevoise par Jean STAROBINSKI et un chapitre sur l'Europe savante (1700-1850) par Jacques ROGER, sont présentés les travaux et recherches dans les différentes disciplines: l'astronomie par Marcel GOLAY, les mathématiques par Pierre SPEZIALI, la physique par Pierre SPEZIALI, la chimie par Armand BUCHS, la géologie par Albert V. CAROZZI, la zoologie par Marino BUSCAGLIA, la botanique par Jacques NAEF; suivis des biographies des savants genevois par Jean-Michel PICTET, avec petits portraits; notes; index; photos et fac-similés de documents; bibliographies par chapitre. Ouvrage publié par l'Association pour le Musée d'histoire des sciences de Genève, présidé par Jacques TREMBLEY.

  17. Les méthodes nucléaires d’analyse et l’étude des pigments et colorants

    OpenAIRE

    Barrandon, Jean-Noël

    2016-01-01

    Fig. 1. Comparaison de la croissance du nombre des publications en chimie analytique et en analyse par activation ; cette comparaison montre pour les années 50-70 une croissance 6 fois plus rapide (périodicité de 2,2 ans au lieu de 13, 9 ans). Les méthodes nucléaires d’analyse ont vu le jour en 1936 grâce à Von Hevesy ; elles se sont développées rapidement (fig. n° 1) et ont été appliquées à toutes les disciplines des sciences. Bien évidemment, l’archéologie n’a pu échapper à la règle et dès ...

  18. Découvre les sciences avec les petits débrouillards 39 expériences faciles et amusantes

    CERN Document Server

    2006-01-01

    Comment plier des os sans les casser ? Peut-on enlever la rouille d’un vieux clou ? Est-ce facile de multiplier une plante ? Comment fabriquer un mini-geyser ? Un anneau de papier qui n’a qu’une seule face, est-ce possible ? Voilà quelques-unes des 40 énigmes et expériences que ce livre propose aux jeunes lecteurs curieux de comprendre le monde et les phénomènes qui les entourent. Une initiation aux grands principes de la physique, de la chimie et de la biologie, pour s’étonner et aussi épater ses amis ou sa famille.

  19. Le programme « baconien » des chimistes de la Royal Society

    Directory of Open Access Journals (Sweden)

    Luc Peterschmitt

    2008-04-01

    Full Text Available La réception de la philosophie naturelle de Bacon est une réception tronquée, y compris et surtout chez ceux qui se disent baconiens, en particulier à la Royal Society. Nous expliquons ce décalage, en montrant la fonction de la référence à Bacon, à propos de la chimie : même s’il n’est pas authentique, le baconisme de la Royal Society libère un espace théorique pour la chimie, puisqu’il interdit tout a priori portant sur ce que l’on peut admettre au titre de principe de l’explication. Certes, les recherches causales sont des « hypothèses », mais sous couvert d’une précaution parfois rhétorique, elles sont réelles. Mais cela signifie essentiellement, pour les chimistes, que malgré le discours de rupture de la Royal Society, qui se veut fondatrice d’une nouvelle science, ils peuvent s’inscrire dans la continuité de la chimie du 17e siècle. Loin que cela signifie que les chimistes de la Royal Society soient rétrogrades, nous voyons là un signe de la modernité de la chimie. Et si finalement elle s’arrange facilement de la référence à Bacon, c’est peut-être aussi que c’est le genre de science que Bacon a en vue pour sa Grande Restauration.The reception of Bacon’s natural philosophy is paradoxical : it seems that even the “baconists” did not really read or understand Bacon’s works. I try to explain that discrepancy between Bacon’s thought and his epigones by studying the role of the reference to Bacon, as far as chemistry is concerned. In fact, such a baconism, even if it is not genuine, allows chemistry to use its proper principles, since it forbids to decide which are the true principles before the study of natural phenomena. Certainly, discourses about causes are “hypotheses”; but sometimes such a designation is only rhetorical. That signifies that, in spite of the claimed clash which past, the chemists of the Royal Society worked in the directions drawn by the “old” chemistry

  20. Modèle multi-physiques par éléments discrets Applications à la modélisation du troisième corps

    OpenAIRE

    Champelovier, Thibaut; Renouf, Mathieu

    2009-01-01

    International audience; Lorsque deux corps sont en contact, on peut observer à l'interface l'apparition d'une couche hétérogène de quelques micromètres d'épaisseur, plus communément appelée troisième corps. Grâce à la modélisation numérique, on commence aujourd'hui à comprendre sa rhéologie, son rôle mécanique mais aussi thermique. Dans ce contexte, le présent travail propose d'étendre un outil de modélisation discrète aux phénomènes multi-physiques (mécanique, thermique et physico-chimie) et...

  1. Thèses de Doctorat

    Directory of Open Access Journals (Sweden)

    2004-04-01

    Full Text Available Rémi Franckowiak, Le développement des théories du Sel dans la chimie française de la fin du XVIe à celle du XVIIIe siècle Thèse soutenue à l'Université Charles de Gaulle – Lille III le 20 décembre 2002. Composition du Jury : Bernadette Bensaude-Vincent  (Paris-X, François De Gandt (Lille III, Bernard Joly (Lille III, Directeur de thèse, Bernard Maitte (Lille I, Pierre Perrot (Lille I, Lawrence Principe (John Hopkins University.À partir de la fin du XVIe siècle, le Sel dans les doctrine...

  2. CACAO: A project for a laboratory for the production and characterization of thin radioactive layers

    Energy Technology Data Exchange (ETDEWEB)

    Bacri, C.O., E-mail: bacri@ipno.in2p3.f [Institut de Physique Nucleaire d' Orsay, 91406 Orsay Cedex, CNRS (UMR8608-IN2P3), Universite Paris-Sud (Paris XI) (France); Petitbon, V.; Pierre, S. [Institut de Physique Nucleaire d' Orsay, 91406 Orsay Cedex, CNRS (UMR8608-IN2P3), Universite Paris-Sud (Paris XI) (France)

    2010-02-11

    CACAO, Chimie des Actinides et Cibles radioActives a Orsay (actinide chemistry and radioactive targets at Orsay), is a project under construction that consists of the installation of a hot laboratory dedicated to the production and characterization of thin radioactive layers. The project aims to be a joint CNRS-CEA national laboratory to overcome difficulties related mainly to safety issues and to the lack of knowledge and potential manpower. The first goal is to fulfill, at least, the needs of the whole French community, and to be able to coordinate the different activities related to radioactive targets. For this purpose, itis important to be complementary to already existing international installations. Inside this framework, it will of course be possible to produce and/or characterize targets for other users.

  3. CACAO: A project for a laboratory for the production and characterization of thin radioactive layers

    Science.gov (United States)

    Bacri, C. O.; Petitbon, V.; Pierre, S.; Cacao Group

    2010-02-01

    CACAO, Chimie des Actinides et Cibles radioActives à Orsay (actinide chemistry and radioactive targets at Orsay), is a project under construction that consists of the installation of a hot laboratory dedicated to the production and characterization of thin radioactive layers. The project aims to be a joint CNRS-CEA national laboratory to overcome difficulties related mainly to safety issues and to the lack of knowledge and potential manpower. The first goal is to fulfill, at least, the needs of the whole French community, and to be able to coordinate the different activities related to radioactive targets. For this purpose, itis important to be complementary to already existing international installations. Inside this framework, it will of course be possible to produce and/or characterize targets for other users.

  4. Le financement d'une start-up:L'Air Liquide 1898 - 1913

    OpenAIRE

    2003-01-01

    (VF)Au début du 20e siècle, L'air Liquide est une jeune entreprise française créée pour appliquer à l'échelle industrielle les découvertes de la chimie minérale : la liquéfaction de l'air. Les différentes étapes du financement de cette "start-up" ou "société en germe de développement" à l'époque, sont analysées dans le contexte d'incertitude sur la technologie et la production future avec l'implication des différentes classes d'investisseurs et le recours au marché Over The Counter:"la Coulis...

  5. Paramètres Physico-Chimiques & Phytoplancton : Fascicule technique pour la mise en œuvre du suivi "Paramètres Physico-Chimiques & Phytoplancton" du réseau de contrôle de surveillance DCE à La Réunion : Réseau Hydrologique du Littoral Réunionnais

    OpenAIRE

    Duval, Magali; Badat, Faïçal; CAMBERT, Harold; COLLIN, Edouard; Cuet, Pascale; Durasnel, Léonard; HOARAU, Ludovic; Le Goff, Ronan; Maurel, Laurence; Moullama, Alexandre; Ropert, Michel; Scolan, Pierre; Talec, Pascal; Tunin-Ley, Alina; Turquet, Jean

    2015-01-01

    Contractualisation Ifremer/Office de l'eau Réunion. Synthèse collective des travaux menés dans le cadre des Groupes de travail DCE de La Réunion réunissant des experts de l'Université de La Réunion (Lab. ECOMAR), de l'IRD de La Réunion, de l'ARVAM, de PARETO, du GIP RNMR et de la DEAL Réunion sous la coordination de la Délégation Ifremer océan Indien. Comment citer ce document : GT DCE Réunion "Physico-Chimie & Phytoplancton". 2015. Fascicule technique pour la mise en œuvre du suivi " Physico...

  6. Fascicule technique pour la mise en œuvre du suivi "Paramètres Physico-Chimiques & Phytoplancton" du réseau de contrôle de surveillance DCE à La Réunion : Réseau Hydrologique du Littoral Réunionnais

    OpenAIRE

    Duval, Magali; Badat, Faïçal; CAMBERT, Harold; COLLIN, Edouard; Cuet, Pascale; Durasnel, Léonard; HOARAU, Ludovic; Le Goff, Ronan; Lochu, Solenn; Mangion, Perrine; Maurel, Laurence; Moullama, Alexandre; Ropert, Michel; Scolan, Pierre; Talec, Pascal

    2016-01-01

    De 2010 à 2012, le projet " Bon Etat : Actualisation de l’état des lieux du SDAGE, volet eaux côtières réunionnaises " (DEAL de La Réunion/Ifremer) a permis la mise en place de 4 groupes de travail DCE experts dont les travaux ont été synthétisés à travers 4 fascicules techniques définissant les conditions de mise en oeuvre des différents suivis du réseau de contrôle de la surveillance (RCS) DCE en milieu marin à la Réunion. Une première version du fascicule "Physico-chimie & phytoplancton", ...

  7. Étude de la composition minérale et organique des liqueurs de thé et de leurs caractéristiques organoleptiques : influence des paramètres physico-chimiques de l'eau

    OpenAIRE

    Mossion, Aurélie

    2007-01-01

    L'analyse de la composition organique et minérale d'infusions réalisées avec différentes variétés de thés et différentes eaux a permis de montrer que la physico-chimie de l'eau (composition, pH, température) contrôle l'extraction des composés présents dans les feuilles et les propriétés organoleptiques des liqueurs obtenues. Le calcium, en particulier, présent sous forme libre, diminue l'extraction des éléments minéraux, des polyphénols et de la caféine du fait de sa grande affinité pour les ...

  8. Développement durable : environnement, énergie et société

    OpenAIRE

    Tarascon, Jean-Marie

    2014-01-01

    Enseignement. Biodiversité, ses croisements avec l’humanité Leçon inaugurale. Biodiversité : de l’océan et la forêt, à la cité (19 décembre 2013) Bâtie sur la chimie pré-biotique issue d’une géo-diversité antérieure, la biodiversité est née dans l’océan ancestral vers 3850 millions d’années (Ma), quand les premières cellules se sont clonées par scissiparité. La vie s’est ensuite diversifiée dans l’océan durant des milliards et des centaines de millions d’années et se sont alors produits des é...

  9. Nanomatériaux pour la catalyse : le spray a le vent en poupe

    OpenAIRE

    Sanchez, Clement

    2010-01-01

    Clément Sanchez, directeur de l’équipe « Matériaux hybrides » (UMR 7574) du laboratoire de Chimie de la matière condensée Les zéolithes, catalyseurs à base d’alumino-silicates utilisés actuellement pour le raffinage du pétrole, présentent un réseau de micropores de diamètre généralement inférieur à 1nm. Seules de petites molécules peuvent pénétrer dans le réseau pour être efficacement transformées : on cherche donc, depuis plus de 40 ans, à augmenter la taille des pores des catalyseurs tout e...

  10. Cell scientist to watch - Virgile Viasnoff.

    Science.gov (United States)

    Bobrowska, Anna

    2016-02-01

    Virgile earned his first degree in soft matter physics at the École Normale Superieure in Paris. He then moved to Johns Hopkins University in the USA to complete a Masters degree, before returning to Paris to pursue his PhD at the École supérieure de physique et de chimie industrielles (ESPCI) in Francois Lequeux's laboratory. In 2006, after two years as a postdoctoral fellow in the group of Amit Meller at Harvard, Vigile started his own lab at the Centre national de la recherche scientifique (CNRS) at ESPCI. Between 2010 and 2011, Virgile spent two years on sabbatical at the Mechanobiology Institute (MBI) at the University of Singapore. He now holds a dual appointment between CNRS and MBI, and his lab in Singapore investigates how the physical and biochemical parameters of the cellular microenvironment regulate cell-cell adhesion and cell fate.

  11. Low-temperature solvothermal approach to the synthesis of La4Ni3O8 by topotactic oxygen deintercalation.

    Science.gov (United States)

    Blakely, Colin K; Bruno, Shaun R; Poltavets, Viktor V

    2011-07-18

    A chimie douce solvothermal reduction method is proposed for topotactic oxygen deintercalation of complex metal oxides. Four different reduction techniques were employed to qualitatively identify the relative reduction activity of each including reduction with H(2) and NaH, solution-based reduction using metal hydrides at ambient pressure, and reduction under solvothermal conditions. The reduction of the Ruddlesden-Popper nickelate La(4)Ni(3)O(10) was used as a test case to prove the validity of the method. The completely reduced phase La(4)Ni(3)O(8) was produced via the solvothermal technique at 150 °C--a lower temperature than by other more conventional solid state oxygen deintercalation methods.

  12. [The story of Annales pharmaceutiques françaises. 1809-2009].

    Science.gov (United States)

    Chast, F

    2009-11-01

    The Annales pharmaceutiques françaises is 200 years old. Initially, in 1809, the Bulletin de pharmacie was the organ of the Société de pharmacie de Paris. The journal was one of the dynamic events stimulated by the law of Germinal in year XI of the French revolution (1803). Its readership increased tremendously, rapidly making it the first regular journal in the pharmaceutical world. In 1984 it became the Journal de pharmacie et chimie published for a century. It was in 1943 that the journal took on its current name of the Annales pharmaceutiques françaises. The journal is now the official organ of the French National Academy of Pharmacy. The six annual issues are supplemented by an internet diffusion allowing readers access in all French-speaking countries.

  13. [Fourcroy and pharmaceutical journals].

    Science.gov (United States)

    Bonnemain, Bruno

    2011-04-01

    Cadet de Gassicourt wrote a brief Eloge of Fourcroy in January 1810 as he died in December of 1809. Fourcroy had a major role concerning the new ideas on the place of pharmacy at the beginning of the 19th century. Fourcroy has had a key influence for the start of several pharmaceutical journals that wanted to emphasize the link between the new chemistry and pharmacy. None of these journals created with him will survive and one has to wait for 1909 to see the creation, without Fourcroy, of a new pharmaceutical journal, the "Journal de Pharmacie" that will become "Journal de Pharmacie et des Sciences accessoires", then "Journal de Pharmacie et de Chimie", before taking the name of"Annales Pharmaceutiques Françaises", the present official journal of the French Academy of Pharmacy. In spite of the essential role of Fourcroy at the start of pharmaceutical journals, Cadet did not even mention it in his Eloge of 1810.

  14. Imaging the experiments on respiration and transpiration of Lavoisier and Séguin: two unknown drawings by Madame Lavoisier.

    Science.gov (United States)

    Beretta, Marco

    2012-01-01

    This paper presents two hitherto unknown drawings by Marie-Anne-Pierrette Lavoisier dating to the early 1790s that illustrate the experiments on respiration and transpiration of her husband Antoine-Laurent Lavoisier and his assistant Armand Séguin. These works may be associated with the well-known sepia drawings that were published for the first time by Edouard Grimaux in 1888. Details contained in these newly discovered drawings by M.me Lavoisier provide fresh evidence as to the nature and aims of Lavoisier's innovative experiments. As we will show, these drawings were intended to illustrate the collection of papers on respiration being prepared by Lavoisier for his Mémoires de physique et de chimie (1792-1805).

  15. [Precarious matters. The radium economy, episteme of risk and the emergence of tracer technique in national socialism].

    Science.gov (United States)

    von Schwerin, Alexander

    2009-01-01

    Following the traces of radioactive material is--as scholars have recently shown--a valuable historical approach in order to evaluate the material 'factor' of science in action. Even though the origins of materials like radium and artificial isotopes are quite different, their circulation is interconnected. A material pathway can be drawn from the radium industry to the scientific rise of artificial isotopes as indicator substances in the 1930s, continuing to the building of networks by German scientists working for the war efforts. Also, this pathway reveals the role of radiation protection in establishing that material culture. Finally, the dynamics of material traces and institutional linkages is shown by the tracer work of biophysicists and radiation biologists working at the Genetic Department of the Kaiser Wilhelm Institute for Brain Research in Berlin and at the Institut de Chimie Nucléaire at Paris, which at that time was occupied by German troops.

  16. Académies et création du savoir scientifique: circulation des idées et mécanismes de la censure

    Directory of Open Access Journals (Sweden)

    Patrizia Delpiano

    2016-12-01

    Full Text Available [Academies and the creation of scientific knowledge: the circulation of ideas and censorships mechanisms]. This article analyses how European academies contributed to shape the idea of scientific truth in the second half of XVIIIth century. It focuses on the role played by academics in disseminating certain theories and censoring other ones, destined to be considered as false beliefs. Two theories stand out: mesmerism, connected to the Viennese physician Franz Anton Mesmer, and the nouvelle chimie, connected to the chemical revolution implemented by Antoine-Laurent Lavoisier. The criteria of scientific truth elaborated by academics influenced the reception of the two theories in France and Italy: mesmerism was received with popular enthusiasm while was condemned by the academic world as the invention of a charlatan; on the opposite, Lavoisier’s chemistry, after initial resistances, was accepted at the institutional level.

  17. Modelling Assisted Design and Synthesis of Highly Porous Materials for Chemical Adsorbents

    Science.gov (United States)

    2010-10-01

    prête bien à l’utilisation de l’hydrogène ou d’autres gaz comme combustibles. Leur porosité, leurs centres métalliques et leur chimie organique se...nouvelle famille de réseaux métallo- organiques a été étudiée et dans laquelle des molécules d’organophosphonate constituent des liens organiques entre...première utilisation d’un tel composé dans un réseau métallo- organique . Les nouveaux liens ont été caractérisés par spectroscopie RMN 1H, 13C et 31P, par

  18. [Clarification on publications concerning the synthesis of acetylsalicylic acid].

    Science.gov (United States)

    Lafont, O

    1996-01-01

    Charles Frédéric Gerhardt (1816-1856) mentioned in his Traité de chimie Organique (1854) a publication, in French (realized in 1852 but published in 1853) entitled "Researches on anhydrous organic acids" in which, was reported the reaction of sodium salicylate with acetyl chloride. He thought that the reaction product was an acid anhydride, but obtained really crude acetylsalicylic acid. Later on, but also in 1853, a publication in german, by the same author related the same experiments. Surprisingly only the second publication has been mentioned in most of the historical studies on the subject. Acetyl salicylic acid was identified and synthesised in 1859 by von Gilm by another method and the product obtained by Gerhardt was identified to it in 1869.

  19. Periodificación en arqueología peruana: genealogía y aporía

    Directory of Open Access Journals (Sweden)

    2005-01-01

    Full Text Available Périodisation en archéologie péruvienne : généalogie et aporie Résumé: La périodisation est un point stratégique d’intersection entre la théorie et la recherche empirique. Son histoire au Pérou résume bien les débats expérimentés par l’archéologie péruvienne. La variété des périodisations postulées et pratiquées dans les Andes l’a transformée en un champ d’étude privilégié. Une fois assumée la réciprocit nécessaire entre le développement d’une discipline et la connaissance de son histoire, l’auteur se livre à cette enquête sur les principaux systèmes de periodisation, les affrontements entre les tendances et le panorama actuel. Ce n’est pas un travail théorique, mais plutôt historiographique sur un aspect spécifique de l’archeologie péruvienne. L’objectif est de faire une généalogie critique et fonctionnelle, c’est-à-dire présenter la genèse des schémas conceptuels utilisés aujourd’hui, leurs liens et leurs limites. La periodificación es un estratégico punto de intersección entre la propuesta teórica y la investigación empírica. Su historia resume bien los debates por los que ha atravesado la arqueología peruana. La variedad de periodificaciones postuladas y/o practicadas en el área central andina, las convierte en un privilegiado campo de estudio. Asumida la necesaria reciprocidad entre el avance de toda disciplina y el conocimiento de su historia, se plantea este recorrido por los principales sistemas de periodificación, los enfrentamientos entre tendencias y el panorama actual. No se trata de un enfoque teórico, antes bien historiográfico de un aspecto específico de la arqueología peruana. El objetivo es hacer una genealogía crítica y funcional, es decir presentar la génesis de los esquemas conceptuales actualmente utilizados, sus conexiones y límites. Periodization in Peruvian archaeology: genealogy and apory Abstract: Periodization is a strategic point of intersection

  20. Integration of seismic reflection and geologically balanced profiles; Integration reflexionsseismischer und geologisch bilanzierter Profile

    Energy Technology Data Exchange (ETDEWEB)

    Lambrecht, A. [Trappe Erdoel Erdgas Consultant, Isernhagen (Germany)

    1998-12-31

    Geophysics and geology employ different kinds of techniques in order to preserve the underground structure. These techniques are based on different sets of data, i.e. seismic or geological data. A sensible combination of the two techniques should produce a better model of the ground structure. This study attempts to integrate geologically balanced profiles and seismic reflection data. A balanced geological profile can than be compared with seismic reflection data measured in the field. The geological model is then changed into a seismic model of the underground by means of seismic modeling. Synthetic modeling is based on the acquisition of available field data. The synthetic stack section or the synthetic migration image are then compared to the field data. Deviations between the two can be attributed to speed errors and the fact that balances will never give an unequivocal solution but always present a group of solutions. (orig. MSK). [Deutsch] In der Geophysik und der Geologie werden verschiedene Techniken verwendet, um die Untergrundstruktur zu erhalten. Diese Techniken basieren auf verschiedenen Datensaetzen, z.B. seismische und geologische Daten. Eine sinnvolle Kombination der Techniken sollte ein besseres Abbild des Untergrundes liefern. In dieser Studie wird ein Versuch unternommen geologisch bilanzierte Profile und reflexionsseismische Daten zu integrieren. Soll ein bilanziertes geologisches Profil mit im Feld gemessenen reflexionsseismischen Daten verglichen werden, dann wird das geologische Modell mit Hilfe der seismischen Modellierung in ein seismisches Abbild des Untergrundes verwandelt. Dabei wird die synthetische Modellierung entsprechend der Aquisition der vorliegenden Felddaten durchgefuehrt. Die synthetische Stapelsektion oder das synthetische Migrationsimage werden anschliessend mit den Felddaten verglichen. Abweichungen zwischen beobachteten und Felddaten haben ihre Ursachen sowohl in Geschwindigkeitsfehlern, als auch in der Tatsache, dass eine

  1. Natural gas qualities in the Southern Permian basin; Die Erdgasqualitaeten im suedlichen Permbecken

    Energy Technology Data Exchange (ETDEWEB)

    Gerling, P.; Kockel, F. [BGR, Hannover (Germany); Lokhorst, A.; Geluk, M.C. [TNO, Haarlem (Netherlands); Nicholson, R.A. [British Geological Survey, Nottingham (United Kingdom); Laier, T. [Danmarks og Groenlands Geologiske Undersoegelse, Kopenhagen (Denmark); Pokorski, J. [Panstwowy Instytut Geologiczny, Warsaw (Poland)

    1998-12-31

    There is a substantial amount of molecular and isotopic gas data in the literature but mostly in the archives of companies and geological services. As the geological services of most European countries traditionally contain (confidential and non-confidential) data on geology and resources these institutions from Great Britain, the Netherlands, Denmark, Poland and Germany decided to compile molecular and isotopic natural gas data from the area of the Southern European Permian basin. The partially EU-subsidised project was carried out between 1994 and 1997 (LOKHORST ed. 1998) The atlas is based on existing data and also on newly determined molecular and isotopic gas parameters. Ring analyses of national and international standard gases ensure the quality and comparability of the data thus obtained. The aim of the ``stocktaking`` of natural gas was to describe the gas qualities from the Southern North Sea in the West to the Eastern borders of Poland, to characterise them genetically and to relate the to the geological environment. (orig.) [Deutsch] Ein substantieller Anteil von molekularen und isotopischen Gasdaten existiert, teilweise in der Literatur, vor allem aber in den Archiven der Firmen und der geologischen Dienste. Da die geologischen Dienste der meisten europaeischen Laender traditionell (oeffentliche und vertrauliche) Daten ueber die Geologie und Rohstoffe vorhalten, haben sich diese Institutionen aus Grossbritanien, den Niederlanden, Daenemark, Polen und Deutschlands entschlossen, molekulare und isotopische Erdgasdaten aus dem Bereich des suedlichen europaeischen Permbeckens zu kompilieren. Das partiell von der EU gefoerderte Projekt wurde in den Jahren 1994 bis 1997 durchgefuehrt (LOKHORST ed. 1998). Ausser auf bereits vorhandenen Daten beruht der Atlas auf etwa 200 Neu-Bestimmungen molekularer und isotopischer Gasparameter. Ringanalysen nationaler und internationeler Standardgase gewaehrleisteten die Qualitaet und die Vergleichbarkeit der gewonnenen

  2. Systematic analysis of geothermal plants. Influence of temperatures in consumer systems on the specific cost of the distributed heat; Systemanalytische Erfassung von Nutzungsanlagen hydrogeothermaler Ressourcen. Einfluss der Temperaturen in den Abnehmersystemen auf den Waermegestehungspreis

    Energy Technology Data Exchange (ETDEWEB)

    Schallenberg, K. [GeoForschungsZentrum Potsdam (Germany)

    1997-12-01

    On the basis of a general investigation of the impact of geological situation, thermal water loop and consumer structure on the economy of heating systems, different geothermal plants are analysed in detail. In the study, for example, variations of the temperature conditions in district heating systems were considered while the geologic conditions are maintained. It is shown that the specific costs calculated for the distributed heat are sensitive to the amount of heat extracted from the Earth`s interior. Therefore, it was necessary to make assumptions for the duration curve of the consumer system. An exponential duration curve was verified by comparison with data from an existing district heating system. The calculated specific heat costs for different network layouts are transformed finally into an equivalent investment potential. The results clearly indicate the possibilities for an optimization of the system when investments into the heating network would be made. (orig.) [Deutsch] Hydrogeothermale Nutzungsanlagen wurden auf Basis der Einflussgroessen Geologie, Thermalwasserkreis und Abnehmerstruktur systemanalytisch erfasst. Daraus ergibt sich die Grundlage zum Vergleich verschiedener Anlagen. Nachhaltige Einfluesse auf die Wirtschaftlichkeit von Geothermieanlagen ergeben sich aus der Betriebsweise der Abnehmerstruktur. Die dargestellten Untersuchungen zielen deshalb zunaechst auf die Variation der Temperaturparameter des Netzes und deren Einfluss auf die Waermegestehungskosten ab. Bei diesem Ansatz wurden zunaechst die geologischen Eingangsgroessen konstant gehalten. Grundlage der statischen Kostenrechnung in Anlehnung an VDI 2067 ist eine Kostenzusammenstellung der Einzelkomponenten einer geothermischen Heizzentrale. Um den geothermischen Beitrag zur Waermeversorgung moeglichst genau zu beschreiben, ist die Kenntnis von geordneten Jahresganglinien der Abnehmersysteme erforderlich. Zur mathematischen Beschreibung diente eine Exponentialfunktion, deren

  3. Les clusters moléculaires. Applications en catalyse homogène et hétérogène Molecular Clusters. Applications in Homogeneous and Heterogeneous Catalysis

    Directory of Open Access Journals (Sweden)

    Dorbon M.

    2006-11-01

    Full Text Available Le présent article ne prétend pas être une étude bibliographique complète. II ne s'agit que d'une synthèse dont le but est l'introduction à un secteur de la chimie encore jeune et surtout très vaste et plein d'avenir. Les clusters métalliques sont des composés constitués d'atomes métalliques liés entre eux et généralement entourés de ligands ; ils présentent à la fois certaines des caractéristiques des complexes uninucléaires d'une part et des métaux massiques d'autre part. D'un point de vue fondamental, la chimie des clusters représente un domaine encore neuf et particulièrement vaste. D'un point de vue pratique, leur principal intérêt réside dans le fait que bon nombre d'entre eux ont fait preuve de propriétés catalytiques remarquables tant en mode homogène qu'en mode hétérogène. Ils doivent être pris en considération par les industriels de la chimie car certains peuvent être impliqués dans des réactions aussi importantes que la synthèse de Fischer-Tropsch, l'hydrogénation des oléfines, la réaction de gaz à l'eau et la fixation biologique de l'azote atmosphérique. This article does not pretend to be an exhaustive bibliographic survey. It is merely a synthesis intended as an introduction to a sector of chemistry which is still young and especially is very vast and promising. Metal clusters are compounds made up of metal atours bonded together and generally surrounded by ligands. They have various characteristics of both mono-nuclear complexes and bulk metals. From a fundamental point of view, the chemistry of clusters is still a new and particularly vast field. From a practical point of view, the importance of clusters lies in the fact that a good number of them have shown proof of remarkable catalytic properties, both homogeneous and heterogeneous. They must henceforth be taken into consideration by chemical engineers because some of them may be involved in such important reactions as the Fischer

  4. Atherosclerosis and atherosensitivity in two southwest Algerian desert rodents, Psammomys obesus and Gerbillus gerbillus, and in Rattus norvegicus

    Directory of Open Access Journals (Sweden)

    El-Aoufi S

    2012-09-01

    Full Text Available Salima El-Aoufi,1 Mohamed-Amine Lazourgui,1 Lakhdar Griene,2 Boubekeur Maouche31Laboratoire de Biologie et de Physiologie des Organismes/MMDED, Faculté des Sciences Biologiques, USTHB, El-Alia, Dar El Beida, Algeria; 2Laboratoire d'Hormonologie, Centre Pierre et Marie Curie, C.H.U Mustapha, Algeria; 3Laboratoire de Physicochimie Théorique et Chimie Informatique, Faculté de Chimie, USTHB, El-Alia, Dar El Beida, AlgeriaAbstract: Cardiovascular disease, including atherosclerosis, is the leading cause of death in patients with diabetes worldwide; thus, it is a major medical concern. The endothelium contributes to the control of many vascular functions, and clinical observations show that it is a primary target for diabetic syndrome. To get better insight into the mechanisms underlying atherosclerosis, we studied the interspecific differences in the arterial metabolisms of two, Psammomys obesus and Gerbillus gerbillus, as well as Rattus norvegicus (Wistar rat, well known for its atheroresistance. Twenty-two enzymatic activities and six macromolecular substances were histochemically compared in the two desert species and in Wistar aortas (abdominal and thoracic and arteries (femoral and caudal embedded in a common block. In the healthy adult rodents, enzyme activities were very intense. They demonstrated that aortic myocytes are capable of various synthesis and catabolism processes. However, considering the frequency of atherosclerosis and its phenotypes, significant differences appeared between the species studied. Our comparative study shows that aortic atherosensitive animals have several common metabolic characteristics, which are found in Psammomys rich in metachromatic glycosaminoglycans (involved in the inhibition of lipolysis and in calcification of the organic matrix, reduced activity in enzymes related to the Krebs cycle (weakening energetic power, and low lipolytic enzyme, adenosine triphosphatase, and adenosine diphosphatase activities

  5. How an Anglo-American methodology took root in France.

    Science.gov (United States)

    Laszlo, Pierre

    2011-01-01

    French organic chemistry had a strong nationalistic bent in the immediate aftermath to World War II. It continued to bask in the glow of the pre-World War I Nobel prize awarded jointly in 1912 to Victor Grignard and Paul Sabatier. In addition, the influence of the two mandarins then in power, Charles Prévost at the Sorbonne and Albert Kirrmann, a Dean in Strasbourg who would be called upon as vice-director at the École normale supérieure in Paris, saw to it that the only theory of organic reactions, admissible in the classroom and in the laboratory, was Prévost's. As Mary Jo Nye has shown, a wall was erected against penetration of the ideas of the British school of Ingold and Hughes. Mechanistic chemistry, as was being vigorously studied by the contemporary Anglo-American physical organic chemists, was 'persona non grata' in France. Publication by Bianca Tchoubar, in 1960, of "Les mécanismes réactionnels en chimie organique" opened a breach. The irony was for Dr. Tchoubar, a militant member of the Communist Party and a lady of fierce opinions, to have become a propagandist for the Anglo-American school of mechanistic studies. Truth for her overruled political propaganda. Her little book was revolutionary in the French context of the times. Together with the GECO (Groupe d'étude de chimie organique) summer conferences pioneered by Guy Ourisson after his return from Harvard, it ushered in the new ideas. This historical essay, based on an in-depth study of Tchoubar's book, will include a portrait of this remarkable woman scientist. It will delve at some length into the renewal of French science initiated by De Gaulle's government after his return to power in 1958. The tension in the French scientific establishment of the sixties reflected two opposed versions of nationalism, the one conservative, Malthusian, inner-directed, the other forward-looking, eager for the recovery of national status, seeing a strong French science as a means for asserting national

  6. New structure–activity relationships of chalcone inhibitors of breast cancer resistance protein: polyspecificity toward inhibition and critical substitutions against cytotoxicity

    Directory of Open Access Journals (Sweden)

    Rangel LP

    2013-09-01

    Full Text Available Luciana Pereira Rangel,1,2,* Evelyn Winter,1,3,* Charlotte Gauthier,1 Raphaël Terreux,4 Louise D Chiaradia-Delatorre,5 Alessandra Mascarello,5 Ricardo J Nunes,5 Rosendo A Yunes,5 Tania B Creczynski-Pasa,3 Sira Macalou,1 Doriane Lorendeau,1 Hélène Baubichon-Cortay,1 Antonio Ferreira-Pereira,2 Attilio Di Pietro11Equipe Labellisée Ligue 2013, BMSSI UMR 5086 CNRS/Université Lyon 1, Institut de Biologie et Chimie des Protéines, Lyon, France; 2Department of General Microbiology, Institute of Microbiology, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; 3Department of Pharmaceutical Sciences, PPGFAR, Federal University of Santa Catarina, Florianopolis, Santa Catarina, Brazil; 4Equipe BISI, BMSSI UMR 5086 CNRS/Université Lyon 1, Institut de Biologie et Chimie des Protéines, Lyon, France; 5Department of Chemistry, Federal University of Santa Catarina, Florianopolis, Santa Catarina, Brazil*These authors contributed equally to this workAbstract: Adenosine triphosphate-binding cassette subfamily G member 2 (ABCG2 plays a major role in cancer cell multidrug resistance, which contributes to low efficacy of chemotherapy. Chalcones were recently found to be potent and specific inhibitors, but unfortunately display a significant cytotoxicity. A cellular screening against ABCG2-mediated mitoxantrone efflux was performed here by flow cytometry on 54 chalcone derivatives from three different series with a wide panel of substituents. The identified leads, with submicromolar IC50 (half maximal inhibitory concentration values, showed that the previously identified 2'-OH-4',6'-dimethoxyphenyl, as A-ring, could be efficiently replaced by a 2'-naphthyl group, or a 3',4'-methylenedioxyphenyl with lower affinity. Such a structural variability indicates polyspecificity of the multidrug transporter for inhibitors. At least two methoxyl groups were necessary on B-ring for optimal inhibition, but substitution at positions 3, 4, and 5 induced cytotoxicity

  7. Histoire d'une cité scientifique le campus du CNRS à Gif-sur-Yvette (1946-2016)

    CERN Document Server

    2016-01-01

    L'histoire du campus de Gif-sur-Yvette, cité scientifique de renommée internationale, commence en 1946, à l'heure de la reconstruction de la recherche française, ajuste après le deuxième conflit mondial. L'histoire du campus de Gif-sur-Yvette, cité scientifique de renommée internationale, commence en 1946, à l'heure de la reconstruction de la recherche française, ajuste après le deuxième conflit mondial. À cette époque, l'on cherche à favoriser l'émergence d'études nouvelles, à soutenir les travaux fondamentaux sans s'interdire de réfléchir à leurs applications, ou encore à stimuler l'interdisciplinarité. L'acquisition du domaine par le CNRS reflète alors l'ambition de son directeur, Frédéric Joliot-Curie, de refonder la Recherche scientifique et de restaurer son rayonnement. Depuis, le campus de Gif-sur-Yvette a connu une formidable aventure, aussi bien humaine que scientifique. Pionnier dans de nombreux domaines, en biologie, en chimie mais aussi en sciences du climat et de l'env...

  8. La fin des certitudes temps, chaos et les lois de la nature

    CERN Document Server

    Prigogine, Ilya

    1996-01-01

    « En cette fin de siècle, la question de l'avenir de la science est souvent posée. Je crois que nous sommes seulement au début de l'aventure. Nous assistons à l'émergence d'une science qui n'est plus limitée à des situations simplifiées, idéalisées, mais nous met en face de la complexité du monde réel, une science qui permet à la créativité humaine de se vivre comme l'expression singulière d'un trait fondamental de tous les niveaux de la nature. J'ai tenté de présenter cette transformation conceptuelle qui implique l'ouverture d'un nouveau chapitre dans l'histoire féconde des relations entre physique et mathématique sous une forme lisible et accessible à tout lecteur intéressé par l'évolution de nos idées sur la nature. Nous ne sommes qu'au début de ce nouveau chapitre de l'histoire de notre dialogue avec la nature. » Ilya PrigogineIlya Progogine, prix Nobel de chimie, est professeur à l'université libre de Bruxelles et à l'université du Texas à Austin.

  9. A History of Chemistry (by Bernadette Bensaude-Vincent and Isabelle Stengers)

    Science.gov (United States)

    Kauffman, George B.

    1998-06-01

    translated by Deborah van Dam. Harvard University Press: Cambridge, MA and London, 1997. 305 pp. Illustrations. 16.3 x 24.0 cm. ISBN 0-674-39659-6. $35.00, £23.50. Another history of chemistry? When I studied the subject in 1950 in the late Claude K. Deischer's class at the University of Pennsylvania, our text was Frank J. Moore's A History of Chemistry (1918; 3rd ed., 1939), one of the few books, all written by practicing chemists, then available in English. Now, paradoxically, at a time when such classes are no longer a standard part of the usual undergraduate curriculum, we are treated to a plethora of histories, most written by professional historians of science. In two recent years alone four histories have appeared: David M. Knight's Ideas in Chemistry: A History of the Science (Rutgers University Press, 1992), William H. Brock's The History of Chemistry (Chapman & Hall, 1992), William H. Brock's The Norton History of Chemistry (Norton, 1993), and Bernadette Bensaude-Vincent and Isabelle Stengers's Histoire de la Chimie (Editions de la Decuoverte, 1993). The book under review here is a felicitous English translation of the last-named volume.

  10. Production ultra propre

    CERN Document Server

    Morvan, Gilles

    2011-01-01

    L'ultra propreté se caractérise par l'absence de particules et la maîtrise de la contamination dans un environnement défini. Largement appliquée dans diverses industries (pharmacie, cosmétiques, dispositifs médicaux, chimie fine, biotechnologies, électronique et secteurs de pointe, agroalimentaire, plasturgie…), la technicité dans ce domaine est élevée, car principalement liée à la maîtrise des différentes sources de contaminations (eau, air ambiant, fluides, etc.). Véritable guide pratique, cet ouvrage détaille les points techniques essentiels pour permettre à l’ingénieur de trouver des solutions adéquates à chaque type de projet. La démarche passe par la rédaction de spécifications rigoureuses pour : - l’eau, essentielle à toutes productions, - les équipements de production ultra propre, - la démarche qualité et environnementale, - la démarche de suivi du projet.

  11. GEO-TEP. Development of thermoelectric materials for geothermal energy conversion systems. Final report 2008

    Energy Technology Data Exchange (ETDEWEB)

    Bocher, L.; Weidenkaff, A.

    2008-07-01

    Geothermal heat can be directly converted into electricity by using thermoelectric converters. Thermoelectric conversion relies on intrinsic materials properties which have to be optimised. In this work novel environmentally friendly and stable oxide ceramics were developed to fulfil this task. Thus, manganate phases were studied regarding their potential thermoelectric properties for converting geothermal heat into electricity. Perovskite-type phases were synthesized by applying different methods: the ceramic route, and innovative synthesis routes such as the 'chimie douce' method by bulk thermal decomposition of the citrate precursor or using an USC process, and also the polyol-mediated synthesis route. The crystal structures of the manganate phases are evaluated by XRPD, NPD, and ED techniques while specific microstructures such as twinned domains are highlighted by HRTEM imaging. Besides, the thermal stability of the Mn-oxide phases in air atmosphere are controlled over a wide temperature range (T < 1300 K). The thermoelectric figure of merit ZT was enhanced from 0.021 to 0.3 in a broad temperature range for the studied phases which makes these phases the best perovskitic candidates as n-type polycrystalline thermoelectric materials operating in air at high temperatures. (author)

  12. Modelling of chemical degradation of blended cement-based materials by leaching cycles with Callovo-Oxfordian porewater

    Science.gov (United States)

    Olmeda, Javier; Henocq, Pierre; Giffaut, Eric; Grivé, Mireia

    2017-06-01

    The present work describes a thermodynamic model based on pore water replacement cycles to simulate the chemical evolution of blended cement (BFS + FA) by interaction with external Callovo-Oxfordian (COx) pore water. In the framework of the radioactive waste management, the characterization of the radionuclide behaviour (solubility/speciation, adsorption) in cementitious materials needs to be done for several chemical degradation states (I to IV). In particular, in the context of the deep geological radioactive waste disposal project (Cigéo), cement-based materials will be chemically evolved with time in contact with the host-rock (COx formation). The objective of this study is to provide an equilibrium solution composition for each degradation state for a CEM-V cement-based material to support the adsorption and diffusion experiments reproducing any state of degradation. Calculations have been performed at 25 °C using the geochemical code PhreeqC and an up-to-date thermodynamic database (ThermoChimie v.9.0.b) coupled to SIT approach for ionic strength correction. The model replicates experimental data with accuracy. The approach followed in this study eases the analysis of the chemical evolution in both aqueous and solid phase to obtain a fast assessment of the geochemical effects associated to an external water intrusion of variable composition on concrete structures.

  13. Trivalent Cation Substitution Effect into Layered Double Hydroxides Co 2Fe y Al 1- y(OH) 6Cl· nH 2O: Study of the Local Order . Ionic Conductivity and Magnetic Properties

    Science.gov (United States)

    Intissar, Mourad; Segni, Rachid; Payen, Christophe; Besse, Jean-Pierre; Leroux, Fabrice

    2002-09-01

    A series of layered double hydroxide materials of composition Co 2Fe yAl 1- y(OH) 6Cl· nH 2O (0≤ y≤1) was prepared via chimie douce. The crystalline parameter related to the cation to cation distance obeys the expected variation, showing that the substitution is effective over the entire range. Local order around Co and Fe cations is studied by X-ray absorption spectroscopy. Moduli of the Fourier transform at the Fe K-edge are superimposable, in agreement with an ordered model, although present in small domains since no superlattice is depicted. The ionic resistivity of the samples is highly dependent on the water molecule content. The conductivity is found to be thermally assisted, and the variation of the slope in the Arrhenius diagram is explained by a Vogel-Tamman-Fulcher-type behavior. Magnetic susceptibility measurements support the proposed cation composition and indicate the onset of local magnetic order at low temperature (below 10 K). The inter-sheet distance influences the magnetic response at low temperature, showing the presence of weak interactions between lamellae.

  14. Piloter la sécurité théorie et pratiques sur les compromis et les arbitrages nécessaires

    CERN Document Server

    Amalberti, René

    2013-01-01

    Cet ouvrage fait suite à La Conduite des systèmes à risques publié par l’auteur en 1996 (réédition 2001). Le premier livre mettait l’accent sur la sécurité au niveau des individus, celui-ci met l’accent sur la gouvernance de la sécurité dans les industries et services. La sécurité des systèmes complexes n’a pas perdu son actualité, bien au contraire ; citons la vingtaine de catastrophes aériennes annuelles, les presque aussi fréquentes catastrophes de la chimie, le spectre des accidents nucléaires, sans oublier les problèmes atteignant les services publics en médecine ou dans la finance. La liste serait trop longue pour prétendre être exhaustif. Plus que les morts, c’est la diversité des milieux concernés qui frappe l’imagination, et la gravité croissante des sinistres, avec leurs immenses répercussions économiques. On voit là réunies toutes les racines d’un système en équilibre précaire à l’échelle planétaire : produire toujours plus, avec des outils plus com...

  15. Hybrid materials science: a promised land for the integrative design of multifunctional materials.

    Science.gov (United States)

    Nicole, Lionel; Laberty-Robert, Christel; Rozes, Laurence; Sanchez, Clément

    2014-06-21

    For more than 5000 years, organic-inorganic composite materials created by men via skill and serendipity have been part of human culture and customs. The concept of "hybrid organic-inorganic" nanocomposites exploded in the second half of the 20th century with the expansion of the so-called "chimie douce" which led to many collaborations between a large set of chemists, physicists and biologists. Consequently, the scientific melting pot of these very different scientific communities created a new pluridisciplinary school of thought. Today, the tremendous effort of basic research performed in the last twenty years allows tailor-made multifunctional hybrid materials with perfect control over composition, structure and shape. Some of these hybrid materials have already entered the industrial market. Many tailor-made multiscale hybrids are increasingly impacting numerous fields of applications: optics, catalysis, energy, environment, nanomedicine, etc. In the present feature article, we emphasize several fundamental and applied aspects of the hybrid materials field: bioreplication, mesostructured thin films, Lego-like chemistry designed hybrid nanocomposites, and advanced hybrid materials for energy. Finally, a few commercial applications of hybrid materials will be presented.

  16. Modèles et méthodes stochastiques une introduction avec applications

    CERN Document Server

    Del Moral, Pierre

    2014-01-01

    La théorie des probabilités et des processus stochastiques est sans aucun doute l'un des plus importants outils mathématiques des sciences modernes. Le théorie des probabilité s'illustre dans de nombreux domaines issus de la biologie, de la physique, et des sciences de l'ingénieur : dynamique des populations, traitement du signal et de l'image, chimie moléculaire, économétrie, sciences actuarielles, mathématiques financières, ainsi qu'en analyse de risque. Le but de cet ouvrage est de parcourir les principaux modèles et méthodes stochastiques de cette théorie en pleine expansion. Ce voyage ne nécessite aucun bagage spécifique sur la théorie des processus stochastiques. Les outils d'analyses nécessaires à une bonne compréhension sont donnés au fur et à mesure de leur construction, révélant ainsi leur nécessité. La théorie des processus stochastiques est une extension naturelle de la théorie de systèmes dynamiques à des phénomènes aléatoires. Elle contient des formalisation d'é...

  17. Les mathématiques de la physique quantique

    CERN Document Server

    Basdevant, Jean-Louis

    2009-01-01

    Ce manuel contient les techniques mathématiques indispensables au maniement de la mécanique quantique : son apprentissage aussi bien que sa pratique. Composé de cinq chapitres, il couvre le programme suivant : les probabilités, la théorie des distributions, l'analyse de Fourier, l'analyse hilbertienne et quelques exemples utiles de fonctions spéciales. Le niveau est celui de la licence et du mastère de physique, le langage, celui des étudiants de physique et chimie d'aujourd'hui. Le but de l'auteur est la clarté et l'efficacité. Il présente les concepts et les résultats dans une langue aussi simple et aussi juste que possible au plan mathématique tout en restant digeste pour les applications. A l'appui de cas concrets, il souligne les points de rigueur mathématique qui ne sont traités que dans les ouvrages spécialisés. Outre sa dimension modeste, ce petit livre présente plusieurs avantages car, récent, simple et concis, il contient aussi quelques exercices.

  18. [6-chloro-3-pyridylmethyl-{sup 3}H]neonicotinoids as high-affinity radioligands for the nicotinic acetylcholine receptor: preparation using NaB{sup 3}H{sub 4} and LiB{sup 3}H{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Latli, Bachir; Casida, J.E. [California Univ., Berkeley, CA (United States). Dept. of Environmental Science Policy and Management; Chit Than; Morimoto, Hiromi; Williams, P.G. [Lawrence Berkeley National Lab., CA (United States)

    1996-11-01

    NaB{sup 3}H{sub 4} and LiB{sup 3}H{sub 4} at 78% and 97% isotopic enrichments, respectively, were used in the synthesis of {sup 3}H-labeled 1-(6-chloro-3-pyridyl)-methyl-2-nitromethyleneimidazolidine (CH-IMI) and N`-[(6-chloro-3-pyridyl)methyl]-n``-cyano-n`-methylacetamidine (acetamiprid) (two very potent insecticides) and of 1-(6-chloro-3-pyridyl)methyl-2-iminoimidazolidine (desnitro-IMI) (a metabolite of the commercial insecticides imidacloprid). 6-Chloronicotinoyl chloride was treated with either NaB{sup 3}H{sub 4} in methanol or LiB{sup 3}H{sub 4} in tetrahydrofuran and the resulting alcohol transformed to 2-chloro-5-chloromethylpyridine, which was then coupled to N-cyano-N`-methylacetamidine to give [{sup 3}H] acetamiprid (45 Ci/mmol). 2-Chloro-5-chloro[{sup 3}H]methylpyridine was also reacted with ethylenediamine and the product was either refluxed in absolute ethanol with 1,1-bis(methylthio)-2-nitro-ethylene to provide [{sup 3}H]CH-IMI or reacted in toluene with a solution of cyanogen bromide to produce [{sup 3}H] desnitro-IMI (each 55 Ci/mmol). (author).

  19. Hybrid materials science: a promised land for the integrative design of multifunctional materials

    Science.gov (United States)

    Nicole, Lionel; Laberty-Robert, Christel; Rozes, Laurence; Sanchez, Clément

    2014-05-01

    For more than 5000 years, organic-inorganic composite materials created by men via skill and serendipity have been part of human culture and customs. The concept of ``hybrid organic-inorganic'' nanocomposites exploded in the second half of the 20th century with the expansion of the so-called ``chimie douce'' which led to many collaborations between a large set of chemists, physicists and biologists. Consequently, the scientific melting pot of these very different scientific communities created a new pluridisciplinary school of thought. Today, the tremendous effort of basic research performed in the last twenty years allows tailor-made multifunctional hybrid materials with perfect control over composition, structure and shape. Some of these hybrid materials have already entered the industrial market. Many tailor-made multiscale hybrids are increasingly impacting numerous fields of applications: optics, catalysis, energy, environment, nanomedicine, etc. In the present feature article, we emphasize several fundamental and applied aspects of the hybrid materials field: bioreplication, mesostructured thin films, Lego-like chemistry designed hybrid nanocomposites, and advanced hybrid materials for energy. Finally, a few commercial applications of hybrid materials will be presented.

  20. Étude de l'emploi des peintures thermochromiques dans l'Art contemporain

    Directory of Open Access Journals (Sweden)

    Marjorie Nastro

    2012-06-01

    Full Text Available Cette étude sur l'utilisation des peintures thermochromiques est basée sur un cas concret, l’œuvre Mur - tableau (vert, conçue et réalisée en 2004 par Véronique Joumard. Elle a été menée dans le cadre d'un mémoire de fin d'études à l'École Supérieure d'Art d'Avignon, en collaboration avec le Laboratoire de chimie appliquée à l'art et à l'archéologie de l'Université d'Avignon, l'entreprise GEM'INNOV et la société MINOLTA. Elle a porté sur l’étude de caractéristiques physico-chimiques de ces couleurs dites "thermo-sensibles".This study on the use of thermochromic paintings is based on Véronique Joumard’s artwork Mur – tableau (vert, conceived and made in 2004. This research was led as a graduation project at Avignon’s Superior Art School  in collaboration with the laboratory of Chemistry applied to Art and Archeology (university of Avignon, GEM’INNOV and MINOLTA Ets. It focuses on the  physico-chimical features of “Thermosensitive” colors.

  1. Qualité chimique et biologique du bassin de la Semois (partie Belge

    Directory of Open Access Journals (Sweden)

    LECLERCQ L.

    1996-04-01

    Full Text Available Les eaux du bassin de la Semois belge ont été étudiées, en 25 stations, sous différents aspects complémentaires : chimie, diatomées et invertébrés benthiques. Les méthodes utilisées sont l'indice de pollution organique (IPO, LECLERCQ et VANDEVENNE, 1987, un indice diatomique (ID, LECLERCQ, non publié et l'indice biologique global normalisé (IBGN, AFNOR, 1992. Grâce aux analyses chimiques et diatomiques, nous décrivons différents types d'eaux naturelles, à minéralisation croissante, et différents niveaux de pollution et d'eutrophication. Nous présentons une carte d e qualité détaillée, à l'usage des gestionnaires. Les diatomées apparaissent comme les bioindicateurs les plus fiables pour ces paramètres. Les invertébrés sont moins intéressants à utiliser. Ils sont pratiquement insensibles au type de minéralisation de l'eau (tout au moins au niveau de la famille, qui est le seul niveau d'identification possible en routine, mais ces organismes peuvent être plus sensibles au facteur substrat qu'à la pollution organique, conduisant alors à des estimations erronées.

  2. La théorie quantique en images

    CERN Document Server

    McEvoy, J P

    2014-01-01

    La théorie quantique nous confronte avec les paradoxes bizarres qui contredisent les fondements de la physique classique. Au niveau subatomique, une particule semble savoir ce que font les autres, mais selon « le principe d'incertitude » de Heisenberg, il y a une limite sur la précision des observations. Pourtant, la théorie quantique est étonnamment précise et largement appliquée en chimie et en physique. Cet ouvrage nous emmène dans un voyage où vous rencontrerez Planck, Einstein, Bohr, Heisenberg et Schrödinger, chacun d'entre eux ayant contribué aux concepts de cette théorie révolutionnaire. La dualité onde-particule, l'interprétation de Copenhague, le chat de Schrödinger, le paradoxe EPR etc... sont autant d'expériences et de concepts qui sont décrits dans cet ouvrage.

  3. [The knowledge of animal respiration as a combustion phenomenon].

    Science.gov (United States)

    de Micheli, Alfredo

    2014-01-01

    The different stages leading to knowledge of the phenomenon of animal breathing are going from some writings in Corpus Hippocraticum to Aristoteles' and Galen's works, who considered the heart as the source of the animal heat. Later, Miguel Servet suggested that the inspired air can achieve other functions besides cooling the blood. After that, different explications of the animal heat were raised. About 1770, due to progress of knowledge in the chemistry field, first Mayow and later Black began to consider the animal respiration as a combustion. The important treatise Méthode de nomenclature chimique, published by Guyton de Morveau et al. in 1787 and soon after the Traité élémentaire de chimie de Lavoisier (1789) provided a solid support to Lavoisier's thought. This way on arrived to consider analogous the respiration and combustion phenomena. Studies on the animal respiration phenomenon continued in xix century and in the following century it was possible to apply thermodynamic principles to biology: "generalized thermodynamics". Copyright © 2013 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.

  4. CaMn(1-x)Nb(x)O3 (x < or = 0.08) perovskite-type phases as promising new high-temperature n-type thermoelectric materials.

    Science.gov (United States)

    Bocher, L; Aguirre, M H; Logvinovich, D; Shkabko, A; Robert, R; Trottmann, M; Weidenkaff, A

    2008-09-15

    Perovskite-type CaMn(1-x)Nb(x)O(3+/-delta) (x = 0.02, 0.05, and 0.08) compounds were synthesized by applying both a "chimie douce" (SC) synthesis and a classical solid state reaction (SSR) method. The crystallographic parameters of the resulting phases were determined from X-ray, electron, and neutron diffraction data. The manganese oxidations states (Mn(4+)/Mn(3+)) were investigated by X-ray photoemission spectroscopy. The orthorhombic CaMn(1-x)Nb(x)O(3+/-delta) (x = 0.02, 0.05, and 0.08) phases were studied in terms of their high-temperature thermoelectric properties (Seebeck coefficient, electrical resistivity, and thermal conductivity). Differences in electrical transport and thermal properties can be correlated with different microstructures obtained by the two synthesis methods. In the high-temperature range, the electron-doped manganate phases exhibit large absolute Seebeck coefficient and low electrical resistivity values, resulting in a high power factor, PF (e.g., for x = 0.05, S(1000K) = -180 microV K(-1), rho(1000K) = 16.8 mohms cm, and PF > 1.90 x 10(-4) W m(-1) K(-2) for 450 K 0.3) make these phases the best perovskitic candidates as n-type polycrystalline thermoelectric materials operating in air at high temperatures.

  5. Synthesis temperature effect on the structural features and optical absorption of Zn(1-x)Co(x)Al2O4 oxides.

    Science.gov (United States)

    Gaudon, M; Apheceixborde, A; Ménétrier, M; Le Nestour, A; Demourgues, A

    2009-10-05

    Zinc/cobalt aluminates with spinel-type structure were prepared by a polymeric route, leading to a pure phase with controlled grain size. The prepared pigments were characterized by powder X-ray diffraction Rietveld analyses in order to determine structural features, scanning electron microscopy for morphological investigation, helium pycnometry and (27)Al MAS NMR in order to highlight the occurrence of defects inside the structure, and UV-visible-near-IR spectroscopy to identify electronic transitions responsible for the compounds' color. The green-blue coloration of these pigments is known to be dependent on the sample thermal history. Here, for the first time, the Zn(1-x)Co(x)Al(2)O(4) color is newly interpreted. The pigment is green once synthesized at low temperature (i.e., with diminution of the pigment grain size); this variation was attributed to the appearance of a new absorption band located at about 500 nm, linked to a complex network feature involving Co ions in octahedral sites as well as oxygen and cationic vacancies. Hence, this work shows the possibility of easily getting a nonstoichiometric network with an abnormal cationic distribution from "chimie douce" processes with moderate synthesis temperature, and so various colorations for the same composition.

  6. Enfants, chercheurs et citoyens

    CERN Document Server

    Lederman, Leon

    1998-01-01

    J'ai consacré ma vie à la physique. J'aimerais que tous les enfants aient la chance de satisfaire leur goût pour la recherche et de développer leur intelligence. J'ai découvert à Chicago, chez mon ami Leon Lederman, une méthode d'enseignement des sciences à l'école qui m'a subjugué. J'ai vu, à tous les niveaux, en physique, en chimie, en sciences naturelles et en mathématiques, des enfants qui expérimentaient avec joie, apprenaient les concepts fondamentaux à leur rythme, réfléchissant et discutant. Je voyais en gestation des êtres libres, capables de rechercher une vérité qui ne leur était pas assenée. J'ai voulu confronter des enseignants français du primaire et du secondaire à ces recherches qui ne se limitent pas à l'enseignement primaire. C'est leur regard critique et surtout leurs idées pour notre enseignement que j'ai rassemblés dans ce livre.

  7. En route vers la nano stabilisation de CLIC faisceau principale et focalisation finale

    CERN Document Server

    Artoos, K; Guinchard, M; Hauviller, Claude; Lackner, F; CERN. Geneva. TS Department

    2008-01-01

    Pour atteindre la luminosité voulue de CLIC, la taille transversale du faisceau doit être de l?ordre du nanomètre. Ceci nécessite une stabilité vibratoire des quadripôles du faisceau principal de 1 nm et même 0.1 nm pour les doublets de la focalisation finale. La nano technologie et la nano stabilisation sont des activités qui évoluent rapidement dans l?industrie et centres de recherche pour des applications très variées comme l?électronique, l?optique, la chimie voire la médecine. Cette présentation décrit les avancées techniques nécessaires pour atteindre l?objectif de CLIC et les projets et collaborations R&D prévus pour démontrer la faisabilité de la nano stabilisation de CLIC en 2010.

  8. Bridging gaps in discovery and development: chemical and biological sciences for affordable health, wellness and sustainability.

    Science.gov (United States)

    Chauhan, Prem Man Singh

    2011-05-01

    To commemorate 2011 as the International Year of Chemistry, the Indian Society of Chemists and Biologists organized its 15th International Conference on 'Bridging Gaps in Discovery and Development: Chemical and Biological Sciences for Affordable Health, Wellness and Sustainability' at Hotel Grand Bhagwati, in association with Saurashtra University, Rajkot, India. Anamik Shah, President of the Indian Society of Chemists and Biologists, was organizing secretary of the conference. Nicole Moreau, President of the International Union of Pure and Applied Chemistry and Secretary General of the Comité National de la Chimie, National Centre for Scientific Research France, was chief guest of the function. The four-day scientific program included 52 plenary lectures, 24 invited lectures by eminent scientists in the field and 12 oral presentations. A total of 317 posters were presented by young scientists and PhD students in three different poster sessions. Approximately 750 delegates from India, the USA, UK, France, Switzerland, Germany, Austria, Belgium, Sweden, Japan and other countries attended the conference. The majority of the speakers gave presentations related to their current projects and areas of interest and many of the talks covered synthesis, structure-activity relationships, current trends in medicinal chemistry and drug research.

  9. High-performing mesoporous iron oxalate anodes for lithium-ion batteries.

    Science.gov (United States)

    Ang, Wei An; Gupta, Nutan; Prasanth, Raghavan; Madhavi, Srinivasan

    2012-12-01

    Mesoporous iron oxalate (FeC(2)O(4)) with two distinct morphologies, i.e., cocoon and rod, has been synthesized via a simple, scalable chimie douce precipitation method. The solvent plays a key role in determining the morphology and microstructure of iron oxalate, which are studied by field-emission scanning electron microscopy and high-resolution transmission electron microscopy. Crystallographic characterization of the materials has been carried out by X-ray diffraction and confirmed phase-pure FeC(2)O(4)·2H(2)O formation. The critical dehydration process of FeC(2)O(4)·2H(2)O resulted in anhydrous FeC(2)O(4), and its thermal properties are studied by thermogravimetric analysis. The electrochemical properties of anhydrous FeC(2)O(4) in Li/FeC(2)O(4) cells are evaluated by cyclic voltammetry, galvanostatic charge-discharge cycling, and electrochemical impedance spectroscopy. The studies showed that the initial discharge capacities of anhydrous FeC(2)O(4) cocoons and rods are 1288 and 1326 mA h g(-1), respectively, at 1C rate. Anhydrous FeC(2)O(4) cocoons exhibited stable capacity even at high C rates (11C). The electrochemical performance of anhydrous FeC(2)O(4) is found to be greatly influenced by the number of accessible reaction sites, morphology, and size effects.

  10. Living hybrid materials capable of energy conversion and CO2 assimilation.

    Science.gov (United States)

    Meunier, Christophe F; Rooke, Joanna C; Léonard, Alexandre; Xie, Hao; Su, Bao-Lian

    2010-06-14

    This paper reviews our work on the fabrication of photobiochemical hybrid materials via immobilisation of photosynthetically active entities within silica materials, summarising the viability and productivity of these active entities post encapsulation and evaluating their efficiency as the principal component of a photobioreactor. Immobilisation of thylakoids extracted from spinach leaves as well as whole cells such as A. thaliana, Synechococcus and C. caldarium was carried out in situ using sol-gel methods. In particular, a comprehensive overview is given of the efforts to find the most biocompatible inorganic precursors that can extend the lifetime of the organisms upon encapsulation. The effect of matrix-cell interactions on cell lifetime and the photosynthetic efficiency of the resultant materials are discussed. Precursors based on alkoxides, commonly used in "Chimie Douce" to form porous silica gel, release by-products which are often cytotoxic. However by controlling the formation of gels from aqueous silica precursors and silica nanoparticles acting as "cements" one can significantly enhance the life span of the entrapped organelles and cells. Adapted characteristic techniques have shown survival times of up to 5 months with the photosynthetic production of oxygen recorded as much as 17 weeks post immobilisation. These results constitute a significant advance towards the final goal, long-lasting semi-artificial photobioreactors that can advantageously exploit solar radiation to convert polluting carbon dioxide into useful biofuels, sugars or medical metabolites.

  11. A General and Mild Approach to Controllable Preparation of Manganese-Based Micro- and Nanostructured Bars for High Performance Lithium-Ion Batteries.

    Science.gov (United States)

    Ma, Guo; Li, Sheng; Zhang, Weixin; Yang, Zeheng; Liu, Shulin; Fan, Xiaoming; Chen, Fei; Tian, Yuan; Zhang, Weibo; Yang, Shihe; Li, Mei

    2016-03-07

    One-dimensional (1D) micro- and nanostructured electrode materials with controllable phase and composition are appealing materials for use in lithium-ion batteries with high energy and power densities, but they are challenging to prepare. Herein, a novel ethanol-water mediated co-precipitation method by a chimie douce route (synthesis conducted under mild conditions) has been exploited to selectively prepare an extensive series of manganese-based electrode materials, manifesting the considerable generalizability and efficacy of the method. Moreover, by simply tuning the mixed solvent and reagents, transition metal oxide bars with differing aspect ratios and compositions were prepared with an unprecedented uniformity. Application prospects are demonstrated by Li-rich 0.5 Li2 MnO3 ⋅0.5 LiNi1/3 Co1/3 Mn1/3 O2 bars, which demonstrate excellent reversible capacity and rate capability thanks to the steerable nature of the synthesis and material quality. This work opens a new route to 1D micro- and nanostructured materials by customizing the precipitating solvent to orchestrate the crystallization process.

  12. [Charles Gerhardt's life and work].

    Science.gov (United States)

    Blondel-Mégrelis, Marika

    2008-05-01

    Charles Gerhardt's life and work is rather well-known thanks to Grimaux and Tiffeneau. His reform of the equivalents, his classification, his obtention of organic acid anhydrids and his famous Treatise of Organic Chemistry. His active collaboration to the Revue scientifique et industrielle du Docteur Quesneville, the creation of his Comptes-Rendus des Travaux de Chimie. Are not so often quoted. Thanks to his translations and reviews, German chemical advancements became well known in France Gerhardt was Liebig's translator for almost all his life, even through the fluctuations of their personal relation. He was the representative of German chemistry in France. With Auguste Laurent, with whom he is constantly associated, things need to be examined precisely. Laurent and Gerhardt, friends at a moment, cannot be confounded. Though they worked together for some years, they were not engaged in a similar project. Besides an experimentalist, Laurent was essentially a theorician of chemistry, whereas Gerhardt refused to think about atoms and arrangements. Formulas have to describe relations between facts, in no case anything about arrangements. For posterity however, Gerhardt will be, on the same level as Laurent, the creator of modern chemistry doctrines.

  13. High mass and spatial resolution mass spectrometry imaging of Nicolas Poussin painting cross section by cluster TOF-SIMS.

    Science.gov (United States)

    Noun, M; Van Elslande, E; Touboul, D; Glanville, H; Bucklow, S; Walter, P; Brunelle, A

    2016-12-01

    The painting Rebecca and Eliezer at the Well, which hangs in the Fitzwilliam Museum, Cambridge, UK, is possibly one of the last figure painting executed by Nicolas Poussin at the very end of his life and is usually dated to the early 1660s. In this perspective special feature, Philippe Walter, Alain Brunelle and colleagues give new insights on the artist's working methods by a careful stateof-the-art imaging ToF-SIMS study of one sample taken on the edge of the painting. This approach allowed for the identification of the pigments used in the painting, their nature and components and those of the ground and preparatory layers, with the identification of the binder(s) and possible other additions of organic materials such as glue. This study paves the way to a wider use of ToF-SIMS for the analysis of ancient cultural heritage artefacts. Dr. Walter is the Director of the Molecular and Structural Archeology Laboratory (Université Pierre et Marie Curie, Paris, France). Dr. Brunelle is Head of the Mass Spectrometry Laboratory at the Institut de Chimie des Substances Naturelles (CNRS, Gif-sur-Yvette, France). Their long standing collaboration has led to several seminal publications on the analysis of ancient artefacts by mass spectrometry.

  14. New scintillation materials and scintiblocs for neutron and γ-rays registration

    Science.gov (United States)

    Koroleva, T. S.; Shulgin, B. V.; Pedrini, Ch.; Ivanov, V. Yu.; Raikov, D. V.; Tcherepanov, A. N.

    2005-01-01

    This paper is a short review of some new scintillation materials, scintillation detectors and scintillation systems for registration of gamma-rays, X-rays, neutrons and neutrinos, which have been developed on the level of inventions and a new fundamental level in the Ural State Technical University-UPI (Ekaterinburg, Russia) and Laboratoire de Physico-Chimie des Matériaux Luminescents (Université Lyon 1, France). The part of Russian patents for this area are presented: some most important new scintillation materials (on the base of lithium hydride, silicate compounds, compounds on the base of aluminates, compounds on the base of fluorides and oxyfluorides, compounds on the base of oxides and oxides crystals, glasses and transparent ceramics) and new scintillation devices (on the base of HgI2, on the base of LiKSO4, sandwich-detectors (organic-inorganic-glass-fiber materials), combine detectors, detectors with photodiodes registration and spectrum shifter, surface scintillation structures and screens, and fiber scintillation devices).

  15. Nanocarriers as pulmonary drug delivery systems to treat and to diagnose respiratory and non respiratory diseases

    Directory of Open Access Journals (Sweden)

    Malgorzata Smola

    2008-03-01

    Full Text Available Malgorzata Smola1,2, Thierry Vandamme1, Adam Sokolowski21Université Louis Pasteur, Faculté de Pharmacie, Département de Chimie Bioorganique, Illkirch Graffenstaden, France; 2Wroclaw University of Technology, Faculty of Chemical Engineering, Wroclaw, PolandAbstract: The purpose of this review is to discuss the impact of nanocarriers administered by pulmonary route to treat and to diagnose respiratory and non respiratory diseases. Indeed, during the past 10 years, the removal of chlorofluorocarbon propellants from industrial and household products intended for the pulmonary route has lead to the developments of new alternative products. Amongst these ones, on one hand, a lot of attention has been focused to improve the bioavailability of marketed drugs intended for respiratory diseases and to develop new concepts for pulmonary administration of drugs and, on the other hand, to use the pulmonary route to administer drugs for systemic diseases. This has led to some marketed products through the last decade. Although the introduction of nanotechnology permitted to step over numerous problems and to improve the bioavailability of drugs, there are, however, unresolved delivery problems to be still addressed. These scientific and industrial innovations and challenges are discussed along this review together with an analysis of the current situation concerning the industrial developments.Keywords: nanotechnology, nanocarriers, nanoparticle, liposome, lung, pulmonary drug delivery, drug targeting, respiratory disease, microemulsion, bioavailability, micelle

  16. ASPECTS DE LA TRADUCTION UNIVERSITAIRE EN CONTEXTE PROFESSIONNEL

    Directory of Open Access Journals (Sweden)

    Angelica Valcu

    2006-05-01

    Full Text Available L’enseignement de la traduction à l’université s’est orienté, les dernières années, vers la traduction professionnelle, étant donné le développement du marché demandeur en traduction technique. Ce type de traduction a en vue la méthodologie de la traduction (la traductologie, la formation des étudiants aux outils du traducteur, le renforcement des savoirs thématiques dans différents domaines : droit, chimie, médecine, etc. Une bonne formation des traducteurs suppose, donc, une réflexion théorique rigoureuse de la pratique pédagogique qui aide les étudiants à s’adapter et à s’insérer rapidement dans le monde professionnel. Teaching translation at the university has been lately oriented towards professional translation due to the development of the market demanding technical translation. This type of activity deals with translation methods (traductology, students training in translator’s tools and reinforcing thematic knowledge in different areas: law, chemistry, medicine, etc. A good training of translators implies therefore a rigorous theoretical reflection of the pedagogical practice that helps students to rapidly adapt and integrate in the professional world.

  17. Memorial for Walter E. Meyerhof

    Science.gov (United States)

    Eichler, Jörg

    2007-08-01

    Walter Meyerhof, one of the leading figures in the field of ion-atom collisions, passed away on May 27, 2006. He was 84 years old. He was born in Kiel, Germany, in the same year that his father, Otto Meyerhof, won the Nobel Prize in Medicine for his discovery of energetically important cycles in biological processes. Following his flight from Hitler-Germany in 1938, Walter Meyerhof studied from 1939-1940 at the Ecole de Physique et Chimie Industrielles in Paris, but when France too fell under Nazi occupation, he had to escape once again. In an exciting odyssey via Spain and Portugal he finally reached the United States. He received a doctorate degree in physics at the University of Pennsylvania in Philadelphia in 1946 with a thesis in solid-state physics. In the same year, he became Assistant Professor at the University of Illinois and in 1949 at Stanford University. In 1952 he was promoted to Associate Professor and in 1959 to Full Professor. From 1970 to 1977 he served as a Chairman of the Stanford Physics Department (see Fig. 1).

  18. THE SIXTH FRENCH-ROMANIAN SYMPOSIUM OF APPLIED CHEMISTRY “COFrRoCA 2010” 07 – 10 JULY 2010 – ORLEANS, FRANCE

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    Irina-Claudia Alexa

    2011-02-01

    Full Text Available The Sixth French-Romanian Symposium of Applied Chemistry "COlloque FRanco-ROumain de Chimie Appliquée" – COFrRoCA 2010, organized by the Research Center “Applied Chemistry and Process Engineering” of the "Vasile Alecsandri" University from Bacău (Romania and the Institute of Organic and Analytical Chemistry, University of Orleans (France, took place on 7-10 July, 2010 in Orleans. Over 140 posters, 46 oral communications, 4 conferences and two keynote lectures were presented plenary or in one of the six parralel sesions: Organical and Therapeutical Chemistry, Analytical Sciences, Chemistry and Sustainable Development, Polymers and Supramolecular Chemistry, Process Engineering and Capitalization of Agro Resources. The symposium was attended by over 150 participants. A volume of Abstracts containing 192 contributions from 413 authors representing 18 countries from Europe (Belgium, Bulgaria, France, Italy, Luxemburg, Moldova, Poland, Romania, Spain, Switzerland, Ukraine, United Kingdom, Africa (Algeria, Benin, Morocco, Senegal, Tunisia and North America (USA, has been issued. Best original contributions were selected in order to be published in Scientific Study & Research – Chemistry & Chemical Engineering, Biotechnology, Food Industry.

  19. Bases en technique du vide

    CERN Document Server

    Rouviere, Nelly

    2017-01-01

    Cette seconde édition, 20 ans après la première, devrait continuer à aider les techniciens pour la réalisation de leur système de vide. La technologie du vide est utilisée, à présent, dans de nombreux domaines très différents les uns des autres et avec des matériels très fiables. Or, elle est souvent bien peu étudiée, de plus, c'est une discipline où le savoir-faire prend tout son sens. Malheureusement la transmission par des ingénieurs et techniciens expérimentés ne se fait plus ou trop rapidement. La technologie du vide fait appel à la physique, à la chimie, à la mécanique, à la métallurgie, au dessin industriel, à l'électronique, à la thermique, etc. Cette discipline demande donc de maîtriser des techniques de domaines très divers, et ce n'est pas chose facile. Chaque installation est en soi un cas particulier avec ses besoins, sa façon de traiter les matériaux et celle d'utiliser les matériels. Les systèmes de vide sont parfois copiés d'un laboratoire à un autre et le...

  20. Validation of nine-years of MOPITT V5 NIR using MOZAIC/IAGOS measurements: biases and long term stability

    Directory of Open Access Journals (Sweden)

    A. T. J. de Laat

    2014-06-01

    Full Text Available Validation results from a comparison between Measurement Of Pollution In The Troposphere (MOPITT V5 Near InfraRed (NIR Carbon Monoxide (CO total column measurements and Measurement of Ozone and Water Vapour on Airbus in-service Aircraft (MOZAIC/In-Service Aircraft for a Global Observing System (IAGOS aircraft measurements are presented. A good agreement is found between MOPITT and MOZAIC/IAGOS measurements, consistent with results from earlier studies using different validation data and despite large variability in MOPITT CO total columns along the spatial footprint of the MOZAIC/IAGOS measurements. Validation results improve when taking the large spatial footprint of the MOZAIC/IAGOS data into account. No statistically significant drift was detected in the validation results over the period 2002–2010 at global, continental and local (airport scales. Furthermore, for those situations where MOZAIC/IAGOS measurements differed from the MOPITT a priori, the MOPITT measurements clearly outperformed the MOPITT a priori data, indicating that MOPITT NIR retrievals add value to the MOPITT a priori. Results from a high spatial resolution simulation of the chemistry-transport model MOCAGE (MOdèle de Chimie Atmosphérique à Grande Echelle showed that the most likely explanation for the large MOPITT variability along the MOZAIC-IAGOS profile flight path is related to spatio-temporal CO variability, which should be kept in mind when using MOZAIC/IAGOS profile measurements for validating satellite nadir observations.

  1. Convergence to Self-Similar Regimes in Thin Polymer Films

    Science.gov (United States)

    Benzaquen, Michael; Salez, Thomas; Raphaël, Elie; Elie Raphaël Team; Kari Dalnoki-Veress Team

    2013-03-01

    The surface of a thin liquid film with nonconstant curvature is unstable, as the Laplace pressure drives a flow mediated by viscosity. Recent experiments and theory applied to stepped polymer films have shown excellent agreement and provide a technique for the study of polymer confinement, the glass transition, and slip at the fluid substrate interface to name a few. The thin film equation governs the evolution of the free surface profile in the lubrication approximation. Despite many efforts, this equation remains only partially solved. We present an analytical and numerical study of the thin film equation. Linearising this equation enables us to derive the Green's function of the problem and therefore obtain a complete set of solutions. We show that the solutions of the problem with equilibrium boundary conditions uniformly converge in time towards a first kind self-similar universal attractor. A numerical study enables us to extend our results to the nonlinear thin film equation. Laboratoire Physico-Chimie Théorique, UMR CNRS 7083 Gulliver. ESPCI, 10 rue Vauquelin, 75005, Paris, France.

  2. The hercynian compressive then extensive tectonic of the north flank of the Montagne Noire (southern French Massif Central)

    Science.gov (United States)

    Turpaud, P.; Matte, P.

    2003-04-01

    . It is striking that two superposed phases of ductile shearing occur in the same area with same geometric axes but with opposite shearing sense. The symmetry of the F2 detachment may be inherited from the first compressive thrusting or both phases are inherited from a previous crustal discontinuity. References: Guérangé-Lozes J., Alsac C. (1986). Les nappes varisques de l'albigeois cristallin. Lithostratigraphie, volcanisme et déformations. Geologie de la France, n^o3, p : 71--106

  3. Zur Geschichte der Geowissenschaften im Museum für Naturkunde zu Berlin Teil 4: Das Mineralogische Museum der Universität Berlin unter Christian Samuel Weiss von 1810 bis 1856

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    G. Hoppe

    2001-01-01

    Full Text Available Die Universitätsgründung in Berlin von 1810 war verbunden mit der Übernahme des Lehrbetriebes der aufgelösten Bergakademie, die nur noch in Form des Bergeleveninstituts bzw. Bergelevenklasse für die Finanzierung der Ausbildung der Bergeleven weiter bestand, sowie mit der Übernahme des von der Bergakademie genutzten Königlichen Mineralienkabinetts der preußischen Bergverwaltung als Mineralogisches Museum der Universität. Infolge des Todes von D. L. G. Karsten im Jahre 1810 erhielt der Leipziger Physiker und Mineraloge C. S. Weiss den Lehrstuhl für Mineralogie, den er bis zu seinem Tode 1856 innehatte. Weiss entwickelte die Lehre Werners, die die Mineralogie einschließlich Geologie umfasste, in kristallographischer Hinsicht weiter, während sich später neben ihm zwei seiner Schüler anderen Teilgebieten der Mineralogie annahmen, G. Rose der speziellen Mineralogie und E. Beyrich der geologischen Paläontologie. Der Ausbau der Sammlungen durch eigene Aufsammlungen, Schenkungen und Käufe konnte in starkem Maße fortgesetzt werden, auch zunehmend in paläontologischer Hinsicht, sodass das Mineralogische Museum für das ganze Spektrum der Lehre gut bestückt war. Der streitbare Charakter von Weiss verursachte zahlreiche Reibungspunkte. History of the Geoscience Institutes of the Natural History Museum in Berlin. Part 4 The establishment of the University in Berlin in 1810 resulted in the adoption of the teaching of the dissolved Bergakademie and of the royal Mineralienkabinett of the Prussian mining department, which was used by the Bergakademie before it became the Mineralogical Museum of the University. The Bergakademie continued to exist only as Bergeleveninstitut or Bergelevenklasse for financing the education of the mining students. The physicist and mineralogist C. S. Weiss was offered the chair of mineralogy after the death of D. L. G. Karsten 1810; he had the position to his death in 1856. Weiss developped the crystallographic part

  4. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of the total phosphorus by a Kjeldahl digestion method and an automated colorimetric finish that includes dialysis

    Science.gov (United States)

    Patton, Charles J.; Truitt, Earl P.

    1992-01-01

    A method to determine total phosphorus (TP) in the same digests prepared for total Kjeldahl nitrogen (TKN) determinations is desribed. The batch, high-temperature (block digester), HG(II)-catalyzed digestion step is similar to U.S. Geological Survey methods I-2552-85/I-4552-85 and U.S. Environmental Protection Agency method 365.4 except that sample and reagent volumes are halved. Prepared digests are desolvated at 220 degrees Celsius and digested at 370 degrees Celsius in separate block digesters set at these temperatures, rather than in a single, temperature-programmed block digester. This approach is used in the method escribed here, which permits 40 calibrants, reference waters, and smaples to be digested and resolvated in about an hour. Orthophosphate ions originally present in samples, along with those released during the digestion step, are determined colorimetrically at a rate of 90 tests per hour by an automated version of the phosphoantimonylmolybdenum blue procedure. About 100 microliters of digest are required per determination. The upper concentration limit is 2 milligrams per liter (mg/L) with a method detection limt of 0.01 mg/L. Repeatability for a sample containing approximately 1.6 mg/L of TP in a high suspended-solids matrix is 0.7 percent. Between-day precision for the same sample is 5.0 percent. A dialyzer in the air-segmented continuous flow analyzer provides on-line digest cleanup, eliminated particulates that otherwise would interfere in the colorimetric finish. An single-channel analyzer can process the resolvated digests from two pairs of block digesters each hour. Paired t-test analysis of TP concentrations for approximately 1,600 samples determined by the new method (U.S. Geologial Survey methods I-2610-91 and I-4610-91) and the old method (U.S. Geological Survey methods I-2600-85 and I-4600-85) revealed positive bias in the former of 0.02 to 0.04 mg/L for surface-water samples in agreement with previous studies. Concentrations of total

  5. Alpine fold-and-thrust structures revealed: A 3D model from the Helvetic Zone (Säntis area, Switzerland)

    Science.gov (United States)

    Sala, Paola; Pfiffner, Adrian; Frehner, Marcel

    2013-04-01

    :25.000, Erläuterungen 78 Kempf, T.A., 1966: Geologie des westlichen Säntisgebirges. Beiträge geologische Karte der Schweiz N.F. 128. Pfiffner, O.A., 2011: Structural Map of the Helvetic Zone of the Swiss Alps. Geological Special Map no.128. Explanatory notes. Schlatter, L., 1941: Neue geologische Untersuchungen im mittleren Säntisgebirge. Bericht (Jahrbuch) der St. Gallischen Naturwissenschaftlichen Gesellschaft, Bd. 70.

  6. La geografía del paisaje y el territorio cultural de Los Millares

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    Gusi i Jener, Francesc

    1991-12-01

    éographique ou se déroule. Malgré les données insuffisants du paleoenvironement qui se possédent sur tous les différents établissements qui appartient a la Culture de Los Millares, à l'avis des les auteurs il y avait une plus grande pluviosité, méme une plus ample coverture forestier dans tout le territoire de l'Andalousie orientale et Murcia, et pourtant une climatologie et un paysage géographique tout différent à l'actucl. D'une autre cóté, l'histoire de la recherche dans la Géugraphie s'avait polarisée depuis ses origines autour de ceux qui dessiraient que cette discipline fut plus proche à l'anthropologie et l'histoire, en face d'autres auteurs qui croyaient que son étude devait aborder des aspects simplement physiographiques, indépendamment de l'action humaine dans le milieu natural. On souligne aussi l'absence d'une coopération entre les archéologues el les géographes, pour étudier ensemble les problemes de la recherche à propos des territoires ocuppés pendant les periodes culturelles correspondant à I'Holocene. D'autre part l'apparition de I'Archéologie Spatial. comme une lendance de la recherche attachée a la géographie du territoirc et les différents positions idéologiques et méthodologiques de l'archeologie préhistorique, fréquemment ressemblables celles qui ont été suscitées pour les géographes, permetent comparer beaucoup d'aspects de cettes disciplines, liées étroitement à les sciences de la Terre et de I'Homme.

  7. Book Reviews

    Directory of Open Access Journals (Sweden)

    Redactie KITLV

    2003-04-01

    . Oxford: Butterworth-Heinemann, 2000, xiv + 293 pp., Stephen Page (eds -John McCarthy, Bernard Sellato, Forest, resources and people in Bulungan; Elements for a history of settlement, trade and social dynamics in Borneo, 1880-2000. Jakarta: Center for international forestry research (CIFOR, 2001, ix + 183 pp. -Naomi M. McPherson, Michael French Smith, Village on the edge; Changing times in Papua New Guinea. Honolulu: University of Hawai'i Press, 2002, xviii + 214 pp. -Gert J. Oostindie, Peter van Wiechen, Vademecum van de Oost- en West-Indische Compagnie Historisch-geografisch overzicht van de Nederlandse aanwezigheid in Afrika, Amerika, Azië en West-Australië vanaf 1602 tot heden. Utrecht: Bestebreurtje, 2002, 381 pp. -Gert J. Oostindie, C.L. Temminck Groll, The Dutch overseas; Architectural Survey; Mutual heritage of four centuries in three continents. (in cooperation with W. van Alphen and with contributions from H.C.A. de Kat, H.C. van Nederveen Meerkerk and L.B. Wevers, Zwolle: Waanders/[Zeist]: Netherlands Department for Conservation, [2002]. 479 pp. -Gert J. Oostindie, M.H. Bartels ,Hollanders uit en thuis; Archeologie, geschiedenis en bouwhistorie gedurende de VOC-tijd in de Oost, de West en thuis; Cultuurhistorie van de Nederlandse expansie. Hilversum: Verloren, 2002, 190 pp. [SCHI-reeks 2.], E.H.P. Cordfunke, H. Sarfatij (eds -Henk Schulte Nordholt, Tony Day, Fluid iron; State formation in Southeast Asia. Honolulu: University of Hawai'i Press, 2002, xii + 339 pp. -Nick Stanley, Nicholas Thomas ,Double vision; Art histories and colonial histories in the Pacific. Cambridge: Cambridge University Press, 1999, xii + 289 pp., Diane Losche, Jennifer Newell (eds -Heather Sutherland, David Henley, Jealousy and justice; The indigenous roots of colonial rule in northern Sulawesi. Amsterdam: VU Uitgeverij, 2002, 106 pp. -Gerard Termorshuizen, Piet Hagen, Journalisten in Nederland; Een persgeschiedenis in portretten 1850-2000. Amsterdam: Arbeiderspers, 2002, 600 pp. -Amy E

  8. Petrography and mineral chemistry of metamorphosed mantle peridotites of Nain Ophiolite (Central Iran

    Directory of Open Access Journals (Sweden)

    Nargess Shirdashtzadeh

    2017-07-01

    expense of Ca-free mineral of serpentine. Tremolite were produced after chrysotile, talc, and chlorite, wherever enough Ca2+ ions were released from the associated olivine and/or orthopyroxene by serpentinization. Discussion Petrographical and geochemical studies indicate a greenschist-facies stage (serpentinization and chloritization followed and overprinted by amphibolite-facies metamorphism. The regional metamorphism is verified by the formation of antigorite after lizardite and chrysotile, metamorphic olivine neoblasts after serpentines, chlorite after Cr-spinel, talc after olivine and orthopyroxene, and tremolite after pyroxene, talc, serpentine, and chlorite. The metamorphism imprints on harzburgite and dunite indicate that metamorphism has occurred after melt-rock reactions. Acknowledgment The authors appreciate Prof. Shoji Arai for providing geochemical facilities. References Ghasemi, A. and Talbot, C.J., 2006. A new tectonic scenario for the Sanandaj-Sirjan Zone (Iran. Journal of Asian Earth Science, 26(6: 683-693. Ghazi, J.M., Moazzen, M., Rahgoshay, M. and Shafaii Moghadam, H., 2010. Mineral chemical composition and geodynamic significance of peridotites from Nain ophiolite, Central Iran. Journal of Geodynamics, 49(5: 261-270. Shirdashtzadeh, N., Torabi, G. and Arai, S., 2010. Metamorphism and metasomatism in the Jurassic of Nain ophiolitic mélange, Central Iran. Neues Jahrbuch für Geologie und Paläontologie – Abhandlungen, 255(3: 255–275. Shirdashtzadeh, N., Torabi, G., Meisel, T., Arai, S., Bokhari, S.N.H., Samadi, R. and Gazel, E., 2014a. Origin and evolution of metamorphosed mantle peridotites of Darreh Deh (Nain Ophiolite, Central Iran: Implications for the Eastern Neo-Tethys evolution. Neues Jahrbuch für Geologie und Paläontologie – Abhandlungen, 273(1: 89–120. Shirdashtzadeh, N., Torabi, G. and Samadi, R., 2014b. Geochemistry of pillow lavas and their clinopyroxene: ophiolitic mélanges of Nain and Ashin (Northeast of Isfahan Province

  9. Application of a Detailed Emission Model for Heavy Duty Diesel Engine Simulations Application d'un modèle détaillé d'émissions pour la simulation de gros moteurs diesel

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    Magnusson I.

    2006-12-01

    Full Text Available A detailed chemical model describing the formation of soot and NO is applied to simulate emission formation in a heavy duty diesel engine. Cylinder flow and spray development is simulated using an engine CFD code - Speedstar. Combustion is described using a simple eddy break-up model. Modeling of the emission-chemistry/turbulent-flow interaction is based on a flamelet approach. Contrary to a typical flamelet concept, transport equations are solved for mass fractions of soot and NO. The reason being that these major emission constituencies are assumed to change slowly in comparison to typical time scales for chemical processes or transport processes important for combustion. Chemical reactions leading to production and destruction of soot and NO are, however, assumed to be fast. Soot and NO source terms are therefore evaluated from a flamelet library using a presumed probability density function and integrating over mixture fraction space. Results from simulations are compared to engine measurements inform of exhaust emission data and cylinder pressure. Un modèle avec chimie détaillée décrivant la formation des suies et du NO est appliqué à la simulation de la formation des polluants dans un gros moteur Diesel. L'écoulement et le spray sont modélisés avec le code de calcul Speedstar. La combustion est représentée par le modèle eddy break-up . La modélisation de l'interaction entre l'écoulement turbulent et la chimie des polluants est basée sur une approche de type flamelet . Cependant, à la différence d'autres travaux, des équations de transport pour les fractions massiques de suies et de NO sont résolues. Cela est justifié par la supposition que les temps caractéristiques de formation de ces composés sont longs comparés à ceux associés aux phénomènes de transport et aux réactions chimiques associées à la combustion. Cependant, les vitesses de réaction se rapportant aux suies et au NO sont supposées rapides. Cela

  10. Synthetic Or Reformulated Fuels: a Challenge for Catalysis Carburants de synthèse ou reformulés : un défi pour la catalyse

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    Courty P.

    2006-12-01

    Full Text Available Despite comparative figures for wordwide crude oil and natural gas proven reserves, present time contribution of syngas chemistry to motorfuels remains marginal when the refining industry is faced to main constraints: market demand evolution, stringent specifications and environmental issues. Actually natural gas upgrading via syngas chemistry yields key products (e. g. methanol among which clean motorfuels (ethers, FT products should develop despite the huge investments required, mostly for syngas production. Main challenges and corresponding issues for catalysts and related technologies are identified for Fischer-Tropsch synthesis and motorfuels long-term reformulation. Among other, mastering the chain-growth (FT synthesis improving the FCC products: gasoline, and LCO for Diesel pool. All these issues need significant progresses in catalyst and technology to be solved. Lastly, our economical study, focused on Diesel-fuel production, shows up that clean diesel (from SR-LCO mixtures and FT Diesel reach similar production costs when cheap NG is available. In the future, FT middle distillates should amount to a few percent (5-150 Mt of the 1700-2000 Mt of transport middle distillates expected from oil refining. However they should more and more be a compulsory part of diesel pool if the level of investment for an FT process continues to decrease significantly. Malgré des réserves prouvées en pétrole et en gaz du même ordre de grandeur, la contribution de la chimie du gaz de synthèse à la production de carburants reste marginale, alors que l'industrie du raffinage est confrontée à des contraintes majeures : évolution de la demande, durcissement des spécifications des produits et contraintes environnementales. Cependant, la conversion chimique du gaz, via la chimie du gaz de synthèse, fournit des produits stratégiques (e. g. méthanol parmi lesquels les carburants propres (éthers, produits Fischer-Tropsch devraient se développer, bien

  11. Are They Climbing the Pyramid? Rating Student-Generated Questions in a Game Design Project / Grimpent-ils la pyramide? Évaluation des questions produites par les étudiants dans un projet de conception de jeux

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    Jason Paul Siko

    2013-02-01

    Full Text Available Researchers have examined the use of homemade PowerPoint games as an instructional technique to improve learning outcomes. However, test data have shown no significant difference in performance between high school chemistry students who created games and students who did not (Siko, Barbour, & Toker, 2011. One of the justifications for the use of the games is that students will, with practice, write higher-order questions when constructing the games. Two subject matter experts rated over 2,500 questions from games created by students in an environmental chemistry class through thematic analysis using Bloom’s taxonomy as a coding scheme. The students wrote primarily recall questions, and students who created games on two occasions did not write more questions than students who only created games once. This suggests that changes to the question-writing aspect of the game project may be necessary in order to see improvements in achievement when compared to control groups. Les chercheurs ont étudié l’usage de jeux PowerPoint maison en tant que technique pédagogique visant à améliorer les résultats d'apprentissage. Les données des tests n'ont toutefois révélé aucune différence significative quant au niveau de performance des étudiants du secondaire en chimie ayant créé des jeux et celui des étudiants n’en ayant pas conçus (Siko, Barbour, et Toker, 2011. L’utilisation des jeux est notamment justifiée par l’idée que, pratique aidant, les étudiants écrivent des questions plus complexes lorsqu’ils élaborent des jeux. Au moyen d’une analyse thématique utilisant la taxonomie de Bloom comme système de codification, deux experts chimistes ont évalué plus de 2500 questions provenant de jeux conçus par des étudiants d’une classe de chimie environnementale. Les étudiants ont rédigé principalement des questions faisant appel à la mémoire, et les étudiants ayant créé des jeux à deux reprises n’ont pas produit

  12. Le marché potentiel des tourteaux broyés, leurs propriétés fonctionnelles et applications

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    Morel Aurélie

    2016-07-01

    Full Text Available La demande mondiale en produits bio-sourcés en pleine expansion engendre un intérêt croissant pour la recherche de nouvelles ressources de matières premières. Pour générer une valeur économique accrue dans les filières oléo-protéagineuses, les tourteaux, co-produits de l’extraction de l’huile, présentent des qualités pouvant être exploitées dans des secteurs diversifiés. Ces tourteaux sont principalement commercialisés en alimentation animale, mais restent peu utilisés dans le secteur de la chimie ou encore de l’alimentation humaine. Afin d’en étendre les applications, le prétraitement de la matière par broyage et classification granulométrique offre des perspectives technologiques pour la conception de nouveaux procédés d’extraction de composés d’intérêt. Le présent article a pour objectif : d’examiner la pertinence d’une diversification du marché des tourteaux, hors usage traditionnel et dans le secteur de la chimie; de caractériser la composition chimique des tourteaux ainsi que leurs propriétés techno-fonctionnelles; d’évaluer la faisabilité de valoriser ces tourteaux ainsi que leurs différentes fractions comme substituts ou additifs permettant la réduction de la teneur en produits d’origine fossile, par exemple, dans la production de formulations adhésives pour les panneaux de particules. Pour ce faire, un certain nombre d’actions ont été menées : évaluation du marché potentiel et accessible à partir des cultures métropolitaines; analyse du panorama de la propriété intellectuelle pour les marchés identifiés; caractérisation chimique des tourteaux broyés et de ses fractions solubles et insolubles; applicabilité des différentes fractions obtenues, en termes de pouvoir moussant, émulsifiant et gélifiant; premiers tests d’application à partir de tourteaux de colza et de tournesol dans le domaine des panneaux de bois composite. Les résultats obtenus ont permis : de

  13. Science et technologie du collage

    CERN Document Server

    Cognard, Jacques

    2003-01-01

    L'Homme a su coller avant de savoir écrire et compter. Le collage est en effet l'une des premières techniques d'assemblage d'une structure que l'homme ait utilisée, technique qui n'est devenue science qu'au début du 20e siècle avec la fabrication des premières colles synthétiques. Cette science de l'adhésion a considérablement progressé ces dix dernières années et ce livre présente l'état actuel des connaissances en décrivant les progrès considérables réalisés dans la compréhension des phénomènes fondamentaux qui font qu'un collage tient bien et durablement. Après l'exposé des bases scientifiques nécessaires et des modèles théoriques récents, l'auteur introduit la distinction entre collages faibles et collages forts puis expose les difficultés rencontrées dans les cas pratiques, difficultés souvent dues à la complexité de la chimie des surfaces et des réactions surface-polymère. L'ouvrage se termine par la présentation de quelques applications récentes, en particulier dans...

  14. Conversion chimique du gaz naturel Chemical Conversion of Natural Gas

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    Chaumette P.

    2006-11-01

    Full Text Available Dans cet article sont passés en revue les travaux de recherche et développement et les procédés existants dans le domaine de la conversion chimique du gaz naturel. Les deux voies possibles, conversion directe du méthane et conversion indirecte, via le gaz de synthèse, sont présentées. Tant la préparation d'hydrocarbures utilisables comme carburants, que celle des composés de bases pour la pétrochimie ou la chimie sont évoquées. L'accent est mis sur l'étape clé du développement de chaque procédé qui, selon le produit visé, consiste en la mise au point d'un nouveau système catalytique, en un changement de la technologie du réacteur, ou en la mise au point d'une section fractionnement moins complexe. This article reviews the research and development work and the existing processes in the area of chemical conversion of natural gas. The two possible methods, direct conversion of methane and indirect conversion via synthesis gas, are discussed. The preparation of hydrocarbons that can be used as fuels and the production of building blocks for the petrochemical and chemical industries are both dealt with. The accent is placed on the key step in developing each process. Depending on the target product, this key step consists in working out a new catalytic system, changing reactor technology or engineering a less complex fractionation section.

  15. Autour de l’Oedipus chymicus :

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    Anne-Lise Rey

    2008-03-01

    Full Text Available A partir de la comparaison entre l’Oedipus chymicus de Leibniz écrit en 1710 et ce qui nous a semblé un possible référent, le texte homonyme de J.J Becher de 1664, l’article s’efforce de déterminer les raisons de l’attrait que Leibniz éprouve pour la chimie de son temps. Si les pratiques de codage et de décodage de la démarche alchimique ainsi que l’attention portée aux transformations des états de la matière constituent indéniablement des points de convergence avec la philosophie leibnizienne, il ne nous semble néanmoins pas possible de conclure de là à une influence de la philosophie chimique, et en particulier de la notion de semence, sur la constitution de la monade leibnizienne.Comparing the Leibniz’s Oedipus chymicus, written in 1710, with its possible reference, the homonymous text by J.J. Becher in 1664, this paper tries to determine why Leibniz had such an interest for the chemistry of his time. If the alchemical practices of coding and decoding and the attention alchemists paid to the modifications of the matter are indeed points of convergence with leibnizian philosophy, it’s nevertheless impossible to conclude to an influence of chemical philosophy, especially of the notion of seed, on the constitution of leibnizian’s monad.

  16. Les apports possibles de la phraséologie à la didactique des langues étrangères

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    Mojca Pecman

    2005-12-01

    Full Text Available L'article explore les avantages d'une analyse phraséologique du discours scientifique face aux difficultés de la maîtrise des formules conventionnelles de ce genre dans une langue étrangère, en l'occurrence en anglais. Notre recherche postule en effet l'existence d'une langue commune aux scientifiques, une langue qui transcende les disciplines, et désormais, grâce à l'anglais, les continents. Pour observer les caractéristiques de cette Langue Scientifique Générale un corpus parallèle a été mis en place recueillant des textes de trois domaines connexes : la chimie, la physique et la biologie. Le dépouillement de ce corpus a abouti à une base de données phraséologiques dont les principes qui ont guidé la construction assurent sa réutilisabilité, notamment pour la réalisation d'applications concrètes à destination des apprenants. L'article présente un projet de construction d'un dictionnaire phraséologique multifonction offrant un double accès aux unités phraséologiques (UP, un accès via la forme des UP (fondé sur une approche sémasiologique de la langue et un accès via le sens des UP (fondé sur une approche onomasiologique de la langue.

  17. THz Spectroscopy of Excited Torsional States of Monodeuterated Methyl Formate (DCOOCH_3)

    Science.gov (United States)

    Carvajal, Miguel; Duan, Chuanxi; Yu, Shanshan; Pearson, John; Drouin, Brian; Kleiner, Isabelle

    2016-06-01

    Recently, a measurement of the rotational spectrum of DCOOCH_3 has been carried out in the frequency range from 0.85 to 1.5 THz at Jet Propulsion Laboratory (JPL) (Duan et al. 2015). These JPL data and the available spectroscopic millimeter- and submillimeter-wave data (Margulès et al. 2010 and references therein) of the ground state were analyzed using the Rho Axis Method (RAM) (Kleiner 2010). At present, a new analysis of JPL lines of DCOOCH_3 in the first excited vt=1 torsional states is undertaken. This analysis may help the future identification of vt=1 lines in the interstellar and circumstellar media as was carried out for the vt=0 lines in Orion KL (Margulès et al. 2010). In this communication, the progress of this study is presented as well as a short outline of the spectral analyses accomplished for other methyl formate isotopologues. C. Duan, M. Carvajal, S. Yu, J.C. Pearson, B.J. Drouin, I. Kleiner 2015, A&A, 576, A39 I. Kleiner 2010, J. Mol. Spectroc., 260, 1 L. Margulès, T.R. Huet, J. Demaison, M. Carvajal, I. Kleiner, H. Møllendal, B. Tercero, N. Marcelino, J. Cernicharo 2010, ApJ, 714, 1120 This research is supported by the FIS2014-53448-C2-2-P project (MINECO, Spain), the French PCMI (Programme National de Physique Chimie du Milieu Interstellaire), and the National Natural Science Foundation of China (Grant No. 11174098). Portions of this work is carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. Government sponsorship is acknowledged.

  18. Romanian Words of Arabic Origin: Scientific and Technical Vocabulary

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    Georgeta Rata

    2016-10-01

    Full Text Available There are 141 Romanian words of Arabic origin acquired either directly from Arabic or else indirectly by passing from Arabic into other languages and then into Romanian. Most entered one or more of the Romance languages before entering Romanian. To qualify for this list, a word must be reported in etymology dictionaries as having descended from Arabic. Words associated with the Islamic religion are omitted. Archaic and rare words are also omitted. Given the nature of the journal in which the paper is to be published, the author selected for analysis only about 126 terms belonging to the scientific and technical vocabulary: Adobe, alambic, albatros, alcalin, alchimie, alcool, alfalfa, algebră, algoritm, alidadă, alizarină, amalgam, ambră, anil, antimoniu, azimuth, azur, benjoin, bezoar, bor, cafea, calibre, camfor, carat, carciofoi, caric, cârmâz, carob, chimie, cifru, coton, curcuma, cuşcuş, erg, falafel, fanfară, felucă, fenec, gazelă, gerbil, girafă, halva, hamada, humus, iasomie, jar, julep, kaliu, lac, lămâie, lazurit, liliac, lime, marcasit, masicot, mizenă, muson, nadir, natriu, papagal, rachetă, realgar, sabkha, safari, şah, sandarac, şaorma, şerbet, sirop, sodium, şofran, sorbet, spanac, sumac, tabac, tahân, taifun, talc, tamarin(d, tangerină, tar, tară, tarhon, tarif, tasă, ţechin, ton, varan, zahăr, zenith, zero, zircon, etc. Some of them are obsolescent, but a large number are in everyday use and have been so well assimilated into Romanian that they have produced other words through derivation and composition, or they have acquired new meanings.

  19. FACULTĂȚILE DE LA UNIVERSITATEA DIN CERNĂUȚI (1875-1919

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    Constantin UNGUREANU

    2017-08-01

    Full Text Available În perioada 1875-1919, Universitatea din Cernăuţi a funcţionat cu trei facultăţi: teologie ortodoxă, drept şi filozofie. Un rol aparte în cadrul Universităţii l-a îndeplinit Facultatea de Teologie Ortodoxă. La această facultate au activat 15 pro­fesori titulari, dintre care 13 români şi doi ucraineni. Facultatea de Drept a fost cea mai bine frecventată. Facultatea de Filozofie din Cernăuţi a cuprins mai multe secţii: filozofie, istorie, filologie şi lingvistică, matematică şi ştiinţe naturale, limbi moderne, fizică, chimie. În ajunul războiului, la această facultate activau 28 de catedre, dintre care 16 în domeniul ştiinţelor filologice şi istorice şi 12 în domeniul ştiinţelor naturale.FACULTIES AT THE UNIVERSITY OF CHERNIVTSI (1875-1919During 1875-1919,ChernivtsiUniversitywas comprised of three faculties: orthodox theology, law and philosophy. The Faculty of Orthodox Theology played a special role within the University. This department was comprised of 15 full professors, of which 13 were Romanian and 2 Ukrainians. Faculty of Law was the best frequented. The Faculty of Philosophy in Chernivtsi was comprised of several departments such as philosophy, history, philology and linguistics, mathematics and natural sciences, modern languages, physics and chemistry. Just before the Great War, this Faculty was comprised of 28 departments of which 16 were specialized in philology and history while 12 were specialized in the natural sciences.

  20. [Regarding respiration and the so-called "animal heat." An historical sketch].

    Science.gov (United States)

    de Micheli, A

    2001-01-01

    According to Aristotle and Galen, the essential function of the respiration phenomenon was to cool the blood. Towards the middle of the XVI Century, Miguel Servet suggested, in his treatise Christianismi restitutio..., that the inspired air could have other functions besides cooling the blood. Later, Joseph Black thought that respiration was a combustion. In the light of the advances in chemistry achieved in the XVII Century, the English scientist Adair Crawford and the French chemist Antoine-Laurent Lavoisier conceived, in the second half of that century, the first general and quantitative theories on the origin of animal heat. Both these authors had the conviction that the "inflammable element", which will be called oxygen, was not formed in the pulmonary territory, but could be absorbed by the blood. Oxygen, foreseen by Mayow at the end of XVII Century, was discovered by Joseph Priestley in 1774. Lavoisier gave the name of oxygen to this gas and firmly established that the respiration phenomenon consists essentially in a process of combustion. The mathematician Joseph-Louis Lagrange, native of Turin, suggested that animal heat originates in all breathing tissues. This phenomenon was verified and described in detail by the biologist Lazzaro Spallanzani, professor at the University of Pavia. Dissemination, in the scientific world, of the new chemical nomenclature and of the respiratory theory, closely related to it, was based fundamentally on the works "Méthode de nomenclature chimique..." (1787) and "Traité élémentaire de chimie..." (1789). During the XIX Century, studies on the phenomenon of animal respiration continued and fundamental discoveries in this subject were attained, such as conversion of hemoglobin to oxyhemoglobin once oxygen had been fixed. Now it is possible to study the regulating mechanisms of the energetic metabolism of the myocardium in vivo, which allows decisive interventions in certain cardiopathies, such as in acute ischemic

  1. Millimeter and Submillimeter Wave Spectra of the HCOO^{13}CH_{3} Isotopolog of Methylformate in the Ground State and in the First Excited Torsional State.

    Science.gov (United States)

    Haykal, I.; Margules, L.; Huet, T. R.; Motiyenko, R. A.; Carvajal, M.; Kleiner, I.; Guillemin, J. C.; Tercero, B.; Cernicharo, J.

    2013-06-01

    The detection of nineteen new rotational transitions of the parent molecule of methylformate (HCOOCH_{3}) in the second lowest excited torsional mode (ν_{t} =2) was recently reported in Orion-KL, as well as the detection of eighty new lines corresponding to the two ^{18}O isotopologs of methylformate in their ground states. The laboratory work on HCOO^{13}CH_{3} was continued. A wide spectral range from 50 to 940 GHz was recorded in Lille with the submillimeter-wave spectrometer based on harmonic generation of a microwave synthesizer source, using a multiplication chain of solid state sources (50-100 and 150-940 GHz) and a backward wave oscillator (100-150 GHz), and coupled to a 2.2 m cell. The absolute accuracy of the line positions is better than 30 kHz up to 630 GHz and 50 kHz above. The two states (ν_{t} = 0 and 1) were fitted together using the RAM Hamiltonian of the BELGI program and a new set of 45 parameters was accurately determined. The fit contains 7050 lines corresponding to the ground state up to J = 78 and K_{a} = 34 and 1907 lines related to ν_{t} =1 up to J = 59 and K_{a} = 24. The detection of new ν_{t} =1 lines in Orion KL will be reported and discussed. This work is supported by the French Programme National de Physico-Chimie du Milieu Interstellaire (CNRS), by CNES, and by the Spanish Government through the grants FIS2011-28738-C02-02 and CONSOLIDER 2009-00038. S. Takano, Y. Sakai, S. Kakimoto, M. Sasaki, and K. Kobayashi PASJ. {64}, 89, 2012. B. Tercero, et al. A& A. {538}, A199, 2012. M. Carvajal, et al. A& A. {500}, 1109, 2009.

  2. Flavonoids targeting of IκB phosphorylation abrogates carcinogen-induced MMP-9 and COX-2 expression in human brain endothelial cells

    Directory of Open Access Journals (Sweden)

    Tahanian E

    2011-05-01

    Full Text Available Elizabeth Tahanian¹, Luis Arguello Sanchez¹, Tze Chieh Shiao², René Roy², Borhane Annabi¹¹Centre de Recherche BioMED, ²Centre de Recherche PharmaQAM, Département de chimie, Université du Québec à Montréal, QC, CanadaAbstract: Brain endothelial cells play an essential role as structural and functional components of the blood–brain barrier (BBB. Increased BBB breakdown and brain injury are associated with neuroinflammation and are thought to trigger mechanisms involving matrix metalloproteinase upregulation. Emerging evidence also indicates that cyclooxygenase (COX inhibition limits BBB disruption, but the mechanisms linking metalloproteinase to COX remain unknown. In this study, we sought to investigate the nuclear factor-kappa B (NF-κB signaling pathway, a common pathway in both the regulation of matrix metalloproteinase-9 (MMP-9 and COX-2 expression, and the inhibitory properties of several chemopreventive flavonoids. Human brain microvascular endothelial cells were treated with a combination of phorbol 12-myristate 13-acetate (PMA, a carcinogen documented to increase MMP-9 and COX-2 through NF-κB, and several naturally occurring flavonoids. Among the molecules tested, we found that fisetin, apigenin, and luteolin specifically and dose-dependently antagonized PMA-induced COX-2 and MMP-9 gene and protein expressions as assessed by qRT-PCR, immunoblotting, and zymography respectively. We further demonstrate that flavonoids impact on IκK-mediated phosphorylation activity as demonstrated by the inhibition of PMA-induced IκB phosphorylation levels. Our results suggest that BBB disruption during neuroinflammation could be pharmacologically reduced by a specific class of flavonoids acting as NF-κB signal transduction inhibitors.Keywords: blood–brain barrier, flavonoids, neuroinflammation, NF-κB signal transduction inhibitors

  3. Validity of satellite measurements used for the monitoring of UV radiation risk on health

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    F. Jégou

    2011-06-01

    Full Text Available In order to test the validity of ultraviolet index (UVI satellite products and UVI model simulations for general public information, intercomparison involving three satellite instruments (SCIAMACHY, OMI and GOME-2, the Chemistry and Transport Model, Modélisation de la Chimie Atmosphérique Grande Echelle (MOCAGE, and ground-based instruments was performed in 2008 and 2009. The intercomparison highlighted a systematic high bias of ~1 UVI in the OMI clear-sky products compared to the SCIAMACHY and TUV model clear-sky products. The OMI and GOME-2 all-sky products are close to the ground-based observations with a low 6 % positive bias, comparable to the results found during the satellite validation campaigns. This result shows that OMI and GOME-2 all-sky products are well appropriate to evaluate the UV-risk on health. The study has pointed out the difficulty to take into account either in the retrieval algorithms or in the models, the large spatial and temporal cloud modification effect on UV radiation. This factor is crucial to provide good quality UV information. OMI and GOME-2 show a realistic UV variability as a function of the cloud cover. Nevertheless these satellite products do not sufficiently take into account the radiation reflected by clouds. MOCAGE numerical forecasts show good results during periods with low cloud covers, but are actually not adequate for overcast conditions; this is why Météo-France currently uses human-expertised cloudiness (rather than direct outputs from Numerical Prediction Models together with MOCAGE clear-sky UV indices for its operational forecasts. From now on, the UV monitoring could be done using free satellite products (OMI, GOME-2 and operational forecast for general public by using modelling, as long as cloud forecasts and the parametrisation of the impact of cloudiness on UV radiation are adequate.

  4. Analytical applications and effective properties of a second gradient isotropic elastic material model

    Science.gov (United States)

    Enakoutsa, Koffi

    2015-06-01

    Recently, the works by Toupin, Mindlin, Sokolowski and Germain have been developed following two research streams. In the first one, higher-order gradient continuum models were developed based on the Cauchy tetrahedron argument (see, e.g., dell'Isola and Seppecher in Comptes Rendus de l Academie de Sciences 17 Serie IIb: Mecanique, Physique, Chimie, Astronomie 321:303-308, 1995, Meccanica 32:33-52 1997, Zeitschrift fr Angewandte Mathematik und Physik 63(6):1119-1141, 2012). In the second one, the structure of higher-order gradient models is developed with a view to the applications. In particular in the model of linear isotropic solids proposed by Dell'Isola, Sciarra and Vidoli (DSV), the main constitutive equation is obtained for the case of second gradient models. This model introduces in addition to the two well-known Lame's elastic constants five constitutive constants. The practical applications of this model remain in its infancy since the issue of determining the new moduli it introduces is not yet completely addressed. Also, analytical solutions of simple boundary value problems that can be helpful to grasp some of the physical foundations of this model are missing. This paper aims to address these two issues by providing the analytical solutions for two model problems, a spherical shell subjected to axisymmetric loading conditions and the circular bending of a beam in plane strain, both the beam and the shell obeying the DSV second gradient isotropic elastic model. The solution of the circular bending of a beam has served to grasp some of the physical soundness of the model. A framework based on homogenization under inhomogeneous boundary conditions is also suggested to determine the unknown constitutive constants, which are provided in the particular case of elastic porous heterogeneous materials.

  5. Low intracellular ATP levels exacerbate carcinogen-induced inflammatory stress response and inhibit in vitro tubulogenesis in human brain endothelial cells

    Directory of Open Access Journals (Sweden)

    Elizabeth Tahanian

    2011-01-01

    Full Text Available Elizabeth Tahanian, Sabrina Peiro, Borhane AnnabiLaboratoire d'Oncologie Moléculaire, Centre de Recherche BioMED, Département de Chimie, Université du Québec à Montréal, Montréal, Québec, CanadaAbstract: Solid tumor development requires angiogenesis and is correlated to the expression of inflammatory markers through cellular metabolic and energetic adaptation. While high glycolysis rates enable the cancer cell compartment to generate adenosine triphosphate (ATP, very little is known about the impact of low intracellular ATP concentrations within the vascular endothelial cell compartment, which is responsible for tumor angiogenesis. Here, we investigated the effect of 2-deoxy-D-glucose (2-DG, a glucose analog that inhibits glycolysis through intracellular ATP depletion, on human brain microvascular endothelial cell (HBMEC angiogenic properties. While preformed capillaries remained unaffected, we found that in vitro tubulogenesis was dose-dependently decreased by 2-DG and that this correlated with reduced intracellular ATP levels. Procarcinogenic signaling was induced with phorbol 12-myristate 13-acetate (PMA and found to trigger the proinflammatory marker cyclooxygenase-2 (COX-2 and endoplasmic reticulum (ER stress marker GRP78 expression, whose inductions were potentiated when PMA was combined with 2-DG treatment. Inversely, PMA-induced matrix-metalloproteinase-9 (MMP-9 gene expression and protein secretion were abrogated in the presence of 2-DG, and this can be partially explained by reduced nuclear factor-κB signaling. Collectively, we provide evidence for an intracellular ATP requirement in order for tubulogenesis to occur, and we link increases in ER stress to inflammation. A better understanding of the metabolic adaptations of the vascular endothelial cells that mediate tumor vascularization will help the development of new drugs and therapies.Keywords: endoplasmic reticulum stress, MMP-9, COX-2, 2-deoxy-D-glucose, endothelial

  6. Internalization and fate of silica nanoparticles in C2C12 skeletal muscle cells: evidence of a beneficial effect on myoblast fusion

    Directory of Open Access Journals (Sweden)

    Poussard S

    2015-02-01

    Full Text Available Sylvie Poussard,1,2 Marion Decossas,1,2 Olivier Le Bihan,1,2 Stéphane Mornet,3 Grégoire Naudin,1,2 Olivier Lambert1,2 1Institute of Chemistry and Biology of Membranes and Nanoobjects, University of Bordeaux, UMR5248, Pessac, France; 2Institute of Chemistry and Biology of Membranes and Nanoobjects, Centre National de la Recherche Scientifique, Institute of Chemistry and Biology of Membranes and Nanoobjects, UMR5248, Pessac, France; 3ICMCB, Institut de Chimie de la Matière Condensée de Bordeaux, CNRS UPR9048, Université de Bordeaux, Pessac, France Abstract: The use of silica nanoparticles for their cellular uptake capability opens up new fields in biomedical research. Among the toxicological effects associated with their internalization, silica nanoparticles induce apoptosis that has been recently reported as a biochemical cue required for muscle regeneration. To assess whether silica nanoparticles could affect muscle regeneration, we used the C2C12 muscle cell line to study the uptake of fluorescently labeled NPs and their cellular trafficking over a long period. Using inhibitors of endocytosis, we determined that the NP uptake was an energy-dependent process mainly involving macropinocytosis and clathrin-mediated pathway. NPs were eventually clustered in lysosomal structures. Myoblasts containing NPs were capable of differentiation into myotubes, and after 7 days, electron microscopy revealed that the NPs remained primarily within lysosomes. The presence of NPs stimulated the formation of myotubes in a dose-dependent manner. NP internalization induced an increase of apoptotic myoblasts required for myoblast fusion. At noncytotoxic doses, the NP uptake by skeletal muscle cells did not prevent their differentiation into myotubes but, instead, enhanced the cell fusion. Keywords: silica, nanoparticle, muscle, cell encapsulation, transmission electron microscopy, apoptosis

  7. Nucleation of metastable aragonite CaCO3 in seawater.

    Science.gov (United States)

    Sun, Wenhao; Jayaraman, Saivenkataraman; Chen, Wei; Persson, Kristin A; Ceder, Gerbrand

    2015-03-17

    Predicting the conditions in which a compound adopts a metastable structure when it crystallizes out of solution is an unsolved and fundamental problem in materials synthesis, and one which, if understood and harnessed, could enable the rational design of synthesis pathways toward or away from metastable structures. Crystallization of metastable phases is particularly accessible via low-temperature solution-based routes, such as chimie douce and hydrothermal synthesis, but although the chemistry of the solution plays a crucial role in governing which polymorph forms, how it does so is poorly understood. Here, we demonstrate an ab initio technique to quantify thermodynamic parameters of surfaces and bulks in equilibrium with an aqueous environment, enabling the calculation of nucleation barriers of competing polymorphs as a function of solution chemistry, thereby predicting the solution conditions governing polymorph selection. We apply this approach to resolve the long-standing "calcite-aragonite problem"--the observation that calcium carbonate precipitates as the metastable aragonite polymorph in marine environments, rather than the stable phase calcite--which is of tremendous relevance to biomineralization, carbon sequestration, paleogeochemistry, and the vulnerability of marine life to ocean acidification. We identify a direct relationship between the calcite surface energy and solution Mg:Ca [corrected] ion concentrations, showing that the calcite nucleation barrier surpasses that of metastable aragonite in solutions with Mg:Ca ratios consistent with modern seawater, allowing aragonite to dominate the kinetics of nucleation. Our ability to quantify how solution parameters distinguish between polymorphs marks an important step toward the ab initio prediction of materials synthesis pathways in solution.

  8. [From apprenticeship to Nobel Prize: Henri Moissan's fabulous destiny].

    Science.gov (United States)

    Lafont, O

    2008-01-01

    Born in Paris on September 28, 1852, son of an eastern railways' employee and of a dressmaker, Henri Moissan's secondary schooling in Meaux did not allow him to get access to the sesame diploma "baccalauréat" (GCE). In 1869, he did obtain a special certificate of secondary schooling so that he could become an apprentice in watch making. That could have been the end of the story, but dreadful event for France appeared to have beneficial effects for Moissan. Under the threat of the Prussian army, Moissan's family took refuge near Paris. This gave the young Henri the opportunity to register as a student for the second-class pharmacy diploma, which did not need, at the time, the GCE. Moissan became then a trainee in pharmacy in 1871. Meanwhile, he followed the special schooling of "Ecole de chimie" founded by E. Frémy, and then joined the laboratory of Dehérain at the Museum, where he worked in plant physiology. He finally obtained the famous "baccalauréat" (GCE) and could register as a student in first-class pharmacy. He became a pharmacist as well as a doctor in sciences. In 1883, Moissan was named professor at the school of pharmacy in Paris. In 1886, he isolated fluorine by electrolysis of fluorhydric acid, in the presence of potassium fluoride, at a low temperature. He then studied diamond synthesis and gave a start to high temperature chemistry, designing his famous furnace. These findings and many others allowed Moissan to rise to membership in many learned academies around the world. Crowning achievement, Moissan won the Nobel Prize in 1906. A man of culture, collector of autographs and paintings, he died in 1907. Nothing of that would have been possible if there had not been a second-class pharmacist diploma. The history of Henri Moissan is one of a rise from apprenticeship to the Nobel Prize.

  9. A NMR and MD study of the active site of factor Xa by selective inhibitors

    Science.gov (United States)

    Doan, B. T.; Fraternali, F.; Do, Q. T.; Atkinson, R. A.; Palmas, P.; Sklenar, V.; Wildgoose, P.; Strop, P.; Saudek, V.

    1998-02-01

    The structure of two selective inhibitors obtained by the screening of a vast combinatorial library, Ac-Tyr-Ile-Arg-Ile-NH2 and Ac-(4-amino-Phe)-(Cyc.-Gly)-NH2, in the active site of the blood clotting enzyme factor Xa was determined using transferred NOE NMR and simulated annealing (SA) under NMR constraints. The refined structures of the inhibitors were docked in the active site and SA was performed inside the enzyme which has been kept as a rigid charged template. The final structures were optimised by molecular dynamics simulation of the complexes in water. The inhibitors assume a compact, very well defined conformation embedded in the binding site without blocking the catalysis. The model allows to explain the mode of action, affinity and specificity. L'étude structurale d'inhibiteurs du facteur Xa, une enzyme de coagulation, obtenus par chimie combinatoire : Ac-Tyr-Ile-Arg-Ile-NH2, Ac-(4-amino-Phe)-(Cyc.-Gly)-NH2, a été réalisée par RMN NOE de transfert et modélisation moléculaire. Les structures ont été calculées sous contraintes RMN : géométrie de distance, recuit simulé et minimisation, affinées par une recherche conformationnelle et recuit de l'inhibiteur placé dans le site actif et optimisées par simulation de dynamique moléculaire du complexe dans l'eau. L'inhibiteur présente une structure compacte positionnée dans le site d'interaction hors d'accès du site catalytique. Ce modèle permet d'expliquer le mode d'action, l'affinité et la spécificité des peptides.

  10. Aerosol Transport Over Equatorial Africa

    Science.gov (United States)

    Gatebe, C. K.; Tyson, P. D.; Annegarn, H. J.; Kinyua, A. M.; Piketh, S.; King, M.; Helas, G.

    1999-01-01

    Long-range and inter-hemispheric transport of atmospheric aerosols over equatorial Africa has received little attention so far. Most aerosol studies in the region have focussed on emissions from rain forest and savanna (both natural and biomass burning) and were carried out in the framework of programs such as DECAFE (Dynamique et Chimie Atmospherique en Foret Equatoriale) and FOS (Fires of Savanna). Considering the importance of this topic, aerosols samples were measured in different seasons at 4420 meters on Mt Kenya and on the equator. The study is based on continuous aerosol sampling on a two stage (fine and coarse) streaker sampler and elemental analysis by Particle Induced X-ray Emission. Continuous samples were collected for two seasons coinciding with late austral winter and early austral spring of 1997 and austral summer of 1998. Source area identification is by trajectory analysis and sources types by statistical techniques. Major meridional transports of material are observed with fine-fraction silicon (31 to 68 %) in aeolian dust and anthropogenic sulfur (9 to 18 %) being the major constituents of the total aerosol loading for the two seasons. Marine aerosol chlorine (4 to 6 %), potassium (3 to 5 %) and iron (1 to 2 %) make up the important components of the total material transport over Kenya. Minimum sulfur fluxes are associated with recirculation of sulfur-free air over equatorial Africa, while maximum sulfur concentrations are observed following passage over the industrial heartland of South Africa or transport over the Zambian/Congo Copperbelt. Chlorine is advected from the ocean and is accompanied by aeolian dust recirculating back to land from mid-oceanic regions. Biomass burning products are transported from the horn of Africa. Mineral dust from the Sahara is transported towards the Far East and then transported back within equatorial easterlies to Mt Kenya. This was observed during austral summer and coincided with the dying phase of 1997/98 El

  11. Cold pearl surfactant-based blends.

    Science.gov (United States)

    Crombie, R L

    1997-10-01

    Pearlizing agents have been used for many years in cosmetic formulations to add a pearlescent effect. Cold pearl surfactant-based blends are mixtures of glycol stearates and surfactants which can be blended in the cold into a wide range of personal-care formulations to create a pearlescent lustre effect. Under controlled manufacturing conditions constant viscosities and crystalline characteristics can be obtained. The development of these blends has been driven by efforts to improve the economics of adding solid pearlizing agents directly into a hot mix formulation. This paper summarizes the history of pearlizers, describes their advantages and physical chemistry of the manufacturing process. Finally some suggestions for applications are given. Les agents nacrants sont utilises depuis de nombreuses annees dans les formulations cosmetiques pour ajouter un effet nacre. Les melanges a froid a base de tensioactif nacre sont des melanges de stearates de glycol et de tensioactifs qui peuvent etre melanges a froid dans une large gamme de formulations d'hygiene personnelle pour creer un effet de lustre nacre. On peut obtenir des viscosites et des proprietes cristallines constantes avec des conditions de fabrication maitrisees. Le developpement de ces melanges a ete porte par les efforts pour ameliorer les couts de l'ajout d'agents nacrants solides directement dans une formulation melangee de l'ajout d'agents nacrants solides directement dans une formulation melangee a chaud. Cet article resume l'histoire des agents nacrants, decrit leurs avantages et al physico-chimie du procede de fabrication. On emet a la fin cetaines suggestions d'applications.

  12. Research progress in the production and synthesis of furfural%糠醛生产工艺及制备方法研究进展

    Institute of Scientific and Technical Information of China (English)

    张璐鑫; 于宏兵

    2013-01-01

    糠醛是一种应用广泛的化工原料,其现有生产工艺在产率、能耗及环境污染等方面存在较大问题.本文介绍了现有的主流生产工艺如Quaker Oats工艺,Agrifuran工艺,Petrole-chimie工艺,Escher Wyss工艺及Rosenlew工艺存在的不足,分析了半纤维素生成糠醛的机理及水解动力学研究、糠醛生产设备的更新改造.从溶剂体系、催化剂体系、分离方法、加热方式等多方面探讨发展新的糠醛生产工艺.提出今后的研究重点要放在开发绿色的溶剂及催化剂上,以期对生态环境的危害降至最低.%Furfural is a highly versatile and key derivative used in the manufacture of a wide range of important chemicals. However, it is also associated with low yield, energy-intensive and negative environment impact in conventional process for producing furfural. Current mainstream techniques (Quaker Oats, Agrifuran, Petrole-chimie, Escher Wyss and Rosenlew) for furfural production are reviewed; the mechanism and kinetics of hydrolysis of hemicelluloses into furfural are analyzed. The equipment up to date and alteration for furfural production are also discussed. Besides, new furfural manufacturing-processes are analyzed by optimizing solvent, catalyst, separation and heat-up. In order to minimize the impact of furfural production to environment, the research on new green catalyst and solvent system should be more emphasized.

  13. Towards the development of a novel bioinspired functional material: synthesis and characterization of hybrid TiO2/DHICA-melanin nanoparticles.

    Science.gov (United States)

    Pezzella, Alessandro; Capelli, Luigia; Costantini, Aniello; Luciani, Giuseppina; Tescione, Fabiana; Silvestri, Brigida; Vitiello, Giuseppe; Branda, Francesco

    2013-01-01

    A large number of recent literature data focus on modification/modulation of surface chemistry of inorganic materials in order to improve their functional properties. Melanins, a wide class of natural pigments, are recently emerging as a powerful organic component for developing bioinspired active material for a large number of applications from organoelectronics to bioactive compounds. Here we report the use of the approach referred as "chimie douce", involving in situ formation of the hybrids through reactions of precursors under mild conditions, to prepare novel hybrid functional architectures based on eumelanin like 5,6 dihydroxyindole-2-carboxylic acid (DHICA) polymer and TiO2. Two synthesis procedures were carried out to get DHICA-melanin coated TiO2 nanoparticles as well as mixed DHICA/TiO2 hybrid nanostructures. Such systems were characterized through EPR, FT-IR and fluorescence spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD), and TEM microscopy in order to assess the effect of synthesis path as well as of DHICA content on structural, morphological and optical properties of TiO2 nanostructures. In particular, EPR, FT-IR spectra and TGA analysis confirmed the presence of DHICA-melanin in these samples. TEM measurements indicated the formation of the nanoparticles having relatively narrow size distribution with average particle size of about 10nm. DHICA-melanin does act as a morphological agent affecting morphology of hybrid nanostructures. XRD analysis proved that TiO2 hybrid nanoparticles kept anatase structures for DHICA-melanin contents within the range of investigated compositions, i.e. up to 50% wt/wt.

  14. Proposed new Lower Triassic stages in South China

    Institute of Scientific and Technical Information of China (English)

    TONG; Jinnan

    2001-01-01

    [1]Orchard, M., Executive notes from the Chair, Albertiana, 200l, 25: 3.[2]Yin Hongfu, Wu Shunbao, Du Yuansheng et al., South China defined as part of Tethyan sarchipelagic ocean system, Earth Science-Journal of China University of Geosciences (in Chinese with English abstract), 1999, 24(1): 1-12.[3]Tozer, E. T., The Trias and its ammonoids: the Evolution of a time scale, Geol. Surv. Canada, Miscellaneous Report, 1984,35: 1-171.[4]Gaetani, M., Report on the Meeting of the Subcommission, Albertiana, 1992, 10: 6-10.[5]Kozur, H., The problem of the Lower Triassic subdivision and some remarks to the position of the Permian-Triassic boundary, Jahrbuch fuer Geologie B. -A., 1993, 136(4): 795-797.[6]Chen Chuzhen, He Guoxiong, Chen Jinhua et al., Marine Triassic, Stratigraphical Studies in China (1979-1999) (in Chinese). Hefei: China University of Science and Technology Press, 2000, 241-259.[7]Zakharov. Y. D., Proposals on revision of the Siberian standard for the Lower Triassic and candidate stratotype section and point for the Induan-Olenekian boundary, A lbertiana, 1994, 14:44-51.[8]Yin Hongfu, Ding Meihua, Zhang Kexin et al., Dongwuan-Indosinian Ecostratigraphy of Yangtze Platform and its Margins (in Chinese with English summary), Beijing: Science Press, 1995, 1-338.[9]Tong Jinnan, Yang Yin, Advance in the Study of the Lower Triassic conodonts at Meishan Section, Changxing, Zhejiang Province. Chinese Science Bulletin, 1998, 43( 16): 1350-1353.[10]Tong Jinnan, Yin Hongfu, A study on the Griesbachian cyclostratigraphy of Meishan section, Changxing, Zhejiang Province. Journal of Stratigraphy (in Chinese with English abstract), 1999, 23(2): 130-135.[11]Sweet, W. C., Uppermost Permian and Lower Triassic conodonts of the Salt Range and Trans-Indus Ranges, West Pakistan. in Stratigraphic Boundary Problems: Permian and Triassic of West Pakistan (eds., Kummel, B., Teichert, C.), University of Kansas, Department of Geology Special

  15. Traditional application of slates in Uruguay

    Science.gov (United States)

    Morales Demarco, Manuela; Cardenes Van den Eynde, Víctor

    2017-04-01

    width of these mica layers, being the former determinant for roofing slates, as according to Wagner (2007) slates with a number of mica layers per mm lower than 40 are not suitable as roofing and façade slates. All dolomitic slates have mass values below 40 (Morales Demarco et al, 2013), but this parameter has not been evaluated for the pelitic slates of Uruguay, and thus it remains unknown the potential of these rocks as roofing slates. Bentz A, Martini HJ (1968) Lehrbuch der Angewandten Geologie, Band 2, 1: Methoden zur Erforschung der Lagerstätten von Erzen, Kohle, Erdöl, Salzen, Industrie-Mineralen und Steinen und Erden. Sttutgart (Enke) DIN EN 12326-2 (2000) Schiefer und andere Natursteinprodukte für überlappende Dachdeckungen und Außenwandbekleidungen. Teil 2: Prüfverfahren. DIN Deutsches Institut für Normung e.V., Beuth, Berlin Morales Demarco M, Oyhantçabal P, Stein K-J, Siegesmund S (2013) Dolomitic slates from Uruguay: petrophysical and petromechanical characterization and deposit evaluation. Environ Earth Sci 69: 1361. doi:10.1007/s12665-012-1921-7 Wagner W (2007) Grundlagen für die Prüfung von Dach- und Wandschiefern. Z dt Ges Geowiss 158(4):785-805

  16. Occurrence of silicate melt, carbonate-rich melt and fluid during medium pressure anatexis of metapelitic gneisses (Oberpfalz, Bavaria) revealed by melt and fluid inclusions study

    Science.gov (United States)

    Ferrero, Silvio; O'Brien, Patrick; Hecht, Lutz; Wunder, Bernd

    2014-05-01

    of a silicate melt and a carbonate-rich melt during anatexis at relatively shallow crustal levels, but this hypothesis needs to be further tested through re-homogenization experiments by piston cylinder means. References Bartoli, O., Cesare, B., Poli, S., Bodnar, R.J., Acosta-Vigil, A., Frezzotti, M.L. & Meli, S., 2013. Recovering the composition of melt and the fluid regime at the onset of crustal anatexis and S-type granite formation. Geology, 41, 115-118. Cesare, B., Ferrero, S., Salvioli-Mariani, E., Pedron, D. & Cavallo, A., 2009. Nanogranite and glassy inclusions: the anatectic melt in migmatites and granulites. Geology, 37, 627-630. Ferrero, S., Bartoli, O., Cesare, B., Salvioli Mariani, E., Acosta-Vigil, A., Cavallo, A., Groppo, C. & Battiston, S., 2012. Microstructures of melt inclusions in anatectic metasedimentary rocks. Journal of Metamorphic Geology, 30, 303-322. Ferrero, S., Braga, R., Berkesi, M., Cesare, B. & Laridhi Ouazaa, N., 2014. Production of Metaluminous melt during fluid-present anatexis: an example from the Maghrebian basement, La Galite Archipelago, central Mediterranean. Journal of Metamorphic Geology, DOI:10.1111/jmg.12068. Tanner, D.C. & Behrmann, J.H., 1995. The Variscan tectonics of the Moldanubian gneisses, Oberpfalzer Wald: a compressional history. Neues Jahrbuch fur Geologie und Palaontologie. Abhandlungen, 197, 331-355. Touret, J.L.R., 2009. Mantle to lower-crust fluid/melt transfer through granulite metamorphism. Russian Geology and Geophysics, 50, 1052-1062.

  17. Water-use data by category, county, and water management district in Florida, 1950-90

    Science.gov (United States)

    Marella, R.L.

    1995-01-01

    The population for Florida in 1990 was estimated at 12.94 million, an increase of nearly 10.17 million (370 percent) from the population of 2.77 million in 1950. Consequently, water use (fresh and saline) in Florida increased nearly 510 percent (15,175 million gallons per day) between 1950 and 1990. The resident population of the State is projected to surpass 20 million by the year 2020. Through the cooperation of the Florida Department of Environ- mental Protection and the U.S. Geologial Survey, water-use data for the period between 1950 and 1990 has been consolidated into one publication. This report aggregates and summarizes the quantities of water withdrawn annually for all water-use categories (public supply, self-supplied domestic, self-supplied commercial-industrial, agriculture, and thermoelectric power generation), by counties, and water management districts in Florida from 1950 through 1990. Total water withdrawn in Florida increased from 2,923 million gallons per day in 1950 to 17,898 million gallons per day in 1990. Surface- water withdrawals during 1950 totaled 2,333 million gallons per day but were not differentiated between fresh and saline, therefore, comparisons between fresh and saline water were made beginning with 1955 data. Freshwater withdrawals increased 245 percent between 1955 and 1990. Saline water withdrawals increased more than 1,500 percent between 1955 and 1990. In 1955, more than 47 percent of the fresh- water used was withdrawn from ground-water sources and 53 percent was withdrawn from surface-water sources. In 1990, nearly 62 percent of the fresh- water withdrawn was from ground-water sources, while 38 percent was withdrawn from surface-water sources. The steady increase in ground-water withdrawals since the 1950's primarily is a result of the ability to drill and pump water more economically from large, deep wells and the reliability of both the quality and quantity of water from these wells. Water withdrawn for public supply in

  18. Contribution to uranium geochemistry in intrusive granites; Contribution a la geochimie de l'uranium dans les granites intrusifs

    Energy Technology Data Exchange (ETDEWEB)

    Coulomb, R. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1959-01-15

    , un certain nombre de massifs granitiques francais: - 3 massifs hercyniens francais, en Vendee, en Bretagne et dans le Morvan, - 1 massif africain, probablement precambrien, du Hoggar. Dans chaque massif, nous determinons en premier lieu le cadre petrochimique et evaluons le degre d'homogeneite chimique des roches. Dans les familles petrochimiques ainsi determinees, nous etudions le comportement geochimique de l'uranium. Du point de vue de la geochimie des granites etudies, le comparaison des lois de repartition des elements majeurs fait apparaitre dans les 4 massifs une convergence de composition moyenne que ne laissaient pas prevoir la geologie et la petrographie. Nous etablissons les lois de repartition statistiques et geographiques de l'uranium total en fonction des variations petrochimiques. L'etude des formes de l'uranium a l'interieur des roches a attire notre attention sur l'importance qualitative et quantitative de la fraction de cet uranium soluble dans les acides dilues. Nous reprenons donc, d'un cote les lois de repartition de l'uranium insoluble qui represente pratiquement l'uranium inclus dans les structures cristallines (zircon, allanite...) et justifions d'un autre cote l'interet presente par l'uranium soluble qui, malgre un caractere plus complexe, permet par son unite geochimique dans les phenomenes postmagmatiques, de trouver une liaison genetique entre les gisements uraniferes et les massifs intrusifs. Nous presentons enfin, un schema du cycle geochimique de l'uranium dans lequel nous esperons avoir pu apporter quelques precisions sur la phase ignee. (auteur)

  19. Heavy-metal contamination of rivers by mining gallery waters during the flood in 2002 in Saxony/Germany and low-cost rapid analysis of contaminated river sediments by XRF

    Science.gov (United States)

    Mucke, D.; Kumann, R.; Mucke, S.

    2012-04-01

    Dieter Mucke, Rolf Kumann, Susanne Mucke GEOMONTAN Gesellschaft für Geologie und Bergbau mbH&Co.KG, Muldentalstrasse 56, 09603 Rothenfurth, Saxony/Germany The Ore Mountains between Bohemia and Saxony are effected by age-long mining for silver mining and winning of other ores. A lot of galleries were driven to keep water away from the mines. Today they still drain off water into the rivers which are used as receiving streams. Sulphide- and sulpharsenide-minerals are unstable. The decomposition of these minerals is caused by the influence of oxygenated drainage water. As a result of this process free cations of iron, copper, lead, zinc, cadmium and residuals of acid (sulphuric acid, acid sulphur, arsenous acid). Already during the transport in the gallery water transformations and precipitations proceed: iron precipitates as sol of iron-(III)-hydroxide-flocks and carries manganese and arsenic, as well as a part of zinc and copper along, on the other hand a bigger part of cadmium keeps in dissolution. From 1844 until 1877 in the silver mining area of Freiberg/Brand-Erbisdorf/Halsbrücke the gallery "Rothschönberger Stolln" was driven with a length of 50 km. In 1995/1996 we determined during four measuring cycles the loads of selected contaminants of five different measuring points in a gallery segment, which takes 29 km. As the annual input into the stream system Triebisch/Elbe with the mudflat of the North Sea as receiving stream we determined: • 19.000 t solid matter (hereof 10.400 t gypsum) • 820 kg cadmium • 420 kg arsenic • 1450 kg lead • 1140 kg copper • 111 t zinc During the flood in August 2002 occurred: • a total sinking of the Münzbach • a partial sinking of the Freiberger Mulde into the Rothschönberger Stolln. Thereby its flow increased from 600 l/sec in average to 10 m3/sec. Over three days during the flood in 2002 water samples were taken and analysed and the discharge was detected. So it was possible to calculate the loads. There was

  20. Fold-related fractures - a brittle tectonic case study of the Helvetic zone in Vorarlberg (western Austria) and Upper Allgäu (Bavaria)

    Science.gov (United States)

    Zerlauth, M.

    2012-04-01

    Michael Zerlauth1,2 , Marcel Schulz1,2 , Hugo Ortner1 , Bernhard Fügenschuh1, Christian Zangerl2 1 Institut für Geologie und Paläontologie, Leopold Franzens Universität, 6020 Innsbruck, Austria 2 alpS-Gmbh, 6020 Innsbruck, Austria In the eastern Alps the Helvetic units exposed at the surface form a narrow belt restricted to the westernmost part of Austria and the northerly adjacent southernmost part of Bavaria. The Helvetic zone represents a Tertiary fold-and-thrust belt made up of Jurassic to Cretaceous shelf sediments deposited on the European margin of the Eurasian plate. In the course of an industry-funded project, the potential of these units for deep hydro-geothermal energy is investigated. Potential targets for hydrothermal exploration are more or less thick carbonate sequences that can be traced throughout the Helvetic zone, namely the Late Jurassic Quinten Limestone and the Early Cretaceous Schrattenkalk-Fm. In depths of at least 3000m below sea level, that have to be drilled to gain water with at least 90°C, uncemented fractures at any scale are the only cavities within these carbonates to be expected. Therefore, brittle structures are studied at differing scales of observation; aerial photos and surface outcrops are analyzed as well as thin sections. All the data obtained so far were collected in areas deformed homogenously: measuring stations were located outside large scale shear zones and either in fold-limbs or hinge zones. A constantly geometrical relationship between the orientation of the various fractures, the sedimentary layering and the trace of the axial planes can be inferred, as already stated by Hancock (1985). Besides extension fractures, veins and stylolithes, conjugated hybrid and shear fractures are quite common, indicating layer-parallel shortening normal to the axial planes as well as axial elongation. Hence, all of the structures observed can be genetically linked with thrusting and folding during regional N-S compressional

  1. Soil formation on hard rock with and without cover of Pleistocene periglacial slope deposits in humid-temperate climate of Europe

    Science.gov (United States)

    Sauer, Daniela; Schülli-Maurer, Isabelle

    2014-05-01

    mainly of beech, birch, fir, pine, and sorb, blueberry and hair-grass (Deschampsia flexuosa). 4) Cambisol developed from Monzonite This soil has an age of ca. 9,500 years. The thickness of the organic surface layer is 6 cm; the mineral soil comprises an Ah (9 cm), Bw (17 cm) and BC (9 cm) horizon. Vegetation consists mainly of fir, oak, beech, and sorb, blueberry, ferns, grasses and mosses. Geochemical data suggest that the soil has not entirely developed from Monzonite but that the Ah and Bw horizon are mainly composed of a thin layer of beach sediments. The comparison demonstrates the importance of physical weathering under periglacial conditions and formation of PPSD for Holocene soil development on hard rock in central Europe. References: Schilling, W., Wiefel, H. (1962): Jungpleistozäne Periglazialbildungen und ihre regionale Differenzierung in einigen Teilen Thüringens und des Harzes. Geologie, Jg. 11, Heft 4: 393 - 504. Semmel, A. (1964): Junge Schuttdecken in Hessischen Mittelgebirgen. Notitzbl. Hess. L.-Amt Bodenforsch. 92: 275 - 285. Semmel, A. (1968): Studien über den Verlauf jungpleistozäner Formung in Hessen. Frankfurter Geogr. Hefte 45.

  2. Isotopic composition of sulfate accumulations, Northern Calcareous Alps, Austria

    Science.gov (United States)

    Bojar, Ana-Voica; Halas, Stanislaw; Bojar, Hans-Peter; Trembaczowski, Andrzej

    2015-04-01

    isotopic compositon of 14 sulfides as galena, sphalerite, pyrite and native sulfure were determined as well, with values ranging between -17.5 and 2.8 ‰ (CDT). For the investigated sulfates, the sulfur isotopic values show generally low values, which are characteristic for the late Permian. The broad distribution of sulfide values point toward bacterial reduction, fact also reflected by some higher isotopic values of sulfates. The oxygen values show a larger scatter from 9 to 23‰, which is even larger than that found for the Zechstein anhydrites of northern Germany, north-eastern Italian Alps or western Poland. The associated carbonates, as calcite, dolomite and magnesite are in disequilibrium with the sulfates indicating rather primary marine isotopic signature than re-equlibration with the sulfates at higher temperatures. References Leitner, C., Neubauer, F., Genser, J., Borojevic-Sostaric, B., Rantitsch, G., 2013. 40Ar/39Ar ages of recrystallization of rock-forming polyhalite in Alpine rocksalt deposits. In Jordan, F., Mark, D.F., Verati C. (eds.) Advances in 40Ar/39Ar Dating: from Archaeology to Planetary Sciences. Geological Society, London, Special Publications, 378, 207-244. Kirchner, E., 1987: Die Mineral- und Gesteinsvorkommen in den Gipslagerstätten der Lammermasse, innerhalb der Hallstattzone, Salzburg. Jahrbuch Haus der Natur. 10, 156-167. Postl, W., 1990. Enargit und Parnauit aus dem Gips- und Anhydritbergbau Tragöß-Oberort, Steiermark. In: Niedermayr, G. et al. (1990): Neue Mineralfunde aus Österreich XXXIX. Carinthia II, 180/100, 277. Tollmann, A., 1977. Geologie von Österreich. Band 1. Die Zentralalpen. Deuticke, Wien, 766 pp.

  3. Persistence of Carbonate Platform Environments in Central Mexico during the Oceanic Anoxic Event 2: impact of the Carribean Plateau?

    Science.gov (United States)

    Bomou, Brahimsamba; Adatte, Thierry; Föllmi, Karl; Arnaud-Vanneau, Annie; Fleitmann, Dominik

    2010-05-01

    the proximity of the Carribean Plateau. The definitive carbonate platform drowning, marked by the deposition of black shales and turbidites, occurs only in the lower Turonian (P. flexuosum), well above the end of the d13C shift. ARTHUR M.A., JENKYNS H.C., BRUMSACK H.J. & SCHLANGER S.O. (1990). Stratigraphy, geochemistry and paleoceanography of organic carbon-rich Cretaceous sequences. In: GINSBURG, R.N. & BEAUDOIN, B., Eds, Cretaceous Resources, Events and Rhythms. NATO ASI Series C, 304, 75-119. JENKYNS H.C. (1980). Cretaceous anoxic events: from continents to oceans. Journal of the Geological Society, 137, 171-188. KURODA J., OGAWA N.O., TANIMIZU M., COFFIN M.F., TOKUYAMA H., KITAZATO H. & OHKOUCHI N. (2007). Contemporaneous massive subaerial volcanism and Late Cretaceous oceanic anoxic event 2. Earth and Planetary Science Letters 256, pp. 211-223. MORT H., ADATTE T., FÖLLMI K., KELLER G., STEINMANN P., MATERA V., BERNER Z., & STÜBEN D. (2007). Phosphorus and the roles of productivity and nutrient recycling during Oceanic Anoxic Event 2. Geology, 35, 6, 483-486. SCHLANGER S.O. & JENKYNS H.C. (1976). Cretaceous anoxic events: causes and consequences. Geologie en Mijnbouw, 55, 179-184. SNOW L.J., DUNCAN R.A., & BRALOWER T.J. (2005). Trace element abundances in the Rock Canyon Anticline, Pueblo, Colorado, marine sedimentary section and their relationship to Caribbean plateau construction and oxygen anoxic event 2. Paleoceanography, 20, doi:10.1029/2004PA001093.

  4. Impact of river restoration on groundwater - surface water - interactions

    Science.gov (United States)

    Kurth, Anne-Marie; Schirmer, Mario

    2014-05-01

    Sensing (DTS), a fibre optical method for temperature determination over long distances (Selker et al., 2006). Thermal signatures were determined in a small urban stream before and after restoration and compared to streams in natural and near-natural settings. BWG BUNDESAMT FÜR WASSER UND GEOLOGIE, 2003. Die Geschichte des Hochwasserschutzes in der Schweiz. Bericht des BWG, Serie Wasser. Biel. 208 p. EA ENVIRONMENT AGENCY (UK), 2009. The Hyporheic Handbook: A handbook on the groundwater-surface water interface and hyporheic zone for environment managers. Bristol. 280 p. ANDREA, F., GSCHÖPF, C., BLASCHKE, A.P., WEIGELHOFER, G., AND RECKENDORFER, W., 2012. Ecological niche models for the evaluation of management options in urban floodplain - conservation vs. restoration purposes. Environ. Sci. Policy, http://dx.doi.org/10.1016/j.envsci.2012.08.011. PALMER, M.A., BERNHARDT, E.S., ALLAN, J.D., LAKE, P.S., ALEXANDER, G., BROOKS, S., CARR, J., CLAYTON, S., DAHM, C.N., FOLLSTAD SHAH, J., GALAT, D.L., LOSS, S.G., GOODWIN, P., HART, D.D., HASSETT, B., JENKINSON, R., KONDOLF, G.M., LAVE, R., MEYER, J.L., O`DONNELL, T.K., PAGANO, L. AND SUDDUTH, E., 2005. Standards for ecologically successful river restoration. Journal of Applied Ecology, 42, pp. 208 - 217. DOI 10.1111/j.1365-2664.2005.01004.x. WORTLEY, L., HERO, J-M., HOWES, M., 2013. Evaluating Ecological Restoration Success: A Review of the Literature. Restoration Ecology, 21 (5), pp. 537 - 543. DOI 10.1111/rec.12028. SELKER, J.S., THEVENAZ, L., HUWALD, H., MALLET, A., LUXEMBURG, W., VAN DE GIESEN, N., STEJSKAL, M., ZEMAN, J., WESTHOFF, M., AND PARLANGE, M.B., 2006. Distributed fibre-optic temperature sensing for hydrologic systems. Water Resources Research, 42(12), W12202.

  5. Fault reactivation and ground uplift assessment at a prospective German CO2 storage site

    Science.gov (United States)

    Röhmann, Lina; Tillner, Elena; Kempka, Thomas; Magri, Fabien; Kühn, Michael

    2013-04-01

    pressure elevation during CO2 injection [4-5]. In the present modelling study 1.7 Mt CO2/year were injected into the top of an anticline structure of the 23 m thick sandstone formation of the Middle Bunter for 20 years of simulation time. A one-way coupling between both simulators was undertaken by transferring the pore pressure distribution from the dynamic flow simulations into the geomechanical simulator for selected time steps. The results show that detailed knowledge on geomechanical processes during CO2 injection is of uttermost importance for the assessment of fault reactivation and ground uplift and associated risks. References [1] Schulz R, Agemar T, Alten AJ, Kühne K, Maul AA, Pester S et al. Implementation of a Geothermal Information System for Germany. - Erdöl Erdgas Kohle 2007, 123(2): 76-81 (in German). [2] Beer H, Stackebrandt W. Geological Map of the State of Brandenburg 1:300.000. Contour Map of the Zechstein Formation Top, 2000. Cottbus: Landesamtes für Bergbau, Geologie und Rohstoffe Brandenburg (in German). [3] Schlumberger. Petrel Seismic-to-Evaluation Software, Version 2010.2.2., 2012. [4] Zhang K, Wu YS, Pruess K. User's Guide for TOUGH2-MP - A Massively Parallel Version of the TOUGH2 Code. Report LBNL-315E, 2008, Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California. [5] Itasca. FLAC3D Software Version 5.0, Advanced Three Dimensional Continuum Modelling for Geotechnical Analysis of Rock, Soil and Structural Support, 2012.

  6. Paleomagnetic Evidence for the Tectono-Stratigraphic Evolution of the Mt.Galili Area / MER / Ethiopia

    Science.gov (United States)

    Popp, F.; Scholger, R.

    2007-12-01

    zone in respect to the migration of the Afar triple junction since~4my *[6]. Another impact of this tectonic environment concerns the generation of weakened zones within the thinned crust induced by crosscutting structural items, subsequently allowing the supply of supercritical crustal melts and finally resulting in explosive eruptions. An extensive dispersed ignimbrite layer (Dhidinley Mb.) yielded an absolute age of ~4,1 my( sanidine, Ar/Ar)*[5]. B: Our stratigraphic age determination of the MGF is focused on magnetic reversal events documented in magmatic layers upon and below the mentioned Dhidinley ignimbrite selfsame demonstrating reverse polarity of its PMV. The uppermost Caashacado Mb. of the MGF exhibits normal polarity contained in gray ignimbrite layers at the top of the pile. We consider this reversal event providing a max. age of 3,58 my (Gauss/Gilbert crossover)*[2]. On the other hand the lowermost lava flow containing normal polarity was excavated by rotational rift block tilting. We consider this reversal event providing a min. age of 4,18 my (Gilbert/Cochiti crossover)*[2]. The mentioned age classifications are consistent with biochronological valuations *[3, 5]. References cited: *[1]: Besse, J. & Courtillot, V. (2002): J.Geophys.Res.107/B11/2300 *[2]: Cande, S.C., & Kent D.V.,(1995): J. Geophys. Res., 100, 6,093-6,095. *[3]: Kullmer O.et al (in rev.): Palaios. *[4]: Macchiarelli R.et al (2004): Coll. Antropol. 28 Suppl 2:65-76. *[5]: Urbanek C. et al (2005): Joannea Geologie und Paläontologie 6: 29-43. *[6]: Wolfenden E.,et al(2004): EPSL 224: 213-228.

  7. Water geochemistry to estimate reservoir temperature of Stabio springs, Switzerland

    Science.gov (United States)

    Pera, Sebastian; Soma, Linda

    2017-04-01

    Elettrica Ticinese References Balderer, W., Leuenberger, F., Frei, C., Surbeck, H., & Synal, H. A. (2007). Origin of the Thermal Waters of Stabio (Switzerland) and Sirmione (Italy) based on Isotope and Chemical Investigations. In Symposium on advances in isotope hydrology and its role in sustainable water resources management; Vienna (Austria); 21-25 May 2007 (Vol. 39, pp. 631-641). IAEA. Bernoulli, D. (1964). Zur Geologie des Monte Generoso. Ein Beitrag zur Kenntnis der südalpinen Sedimente. Beiträge zur Geologischen Karte der Schweiz Karte Schweiz. N.F. 118. Greber, E., Leu, W., Schumacher, M. E., & Wyss, R. (1997). Hydrocarbon provinces in the Swiss Southern Alps-a gas geochemistry and basin modelling study Fsl. Marine and Petroleum Geology, 14(1), 3-25 IAEA. (1984). Isotopes Hydrology 1983. In Proc. Vienna Symposium 1984. Vienna: IAEA

  8. Sandbox Tectonics As A Teaching Tool

    Science.gov (United States)

    Delaughter, J.

    2005-12-01

    obvious manner. Because the experiments produce tangible results, the students experience them on a more visceral level and may be able to incorporate the concepts better than they would through a description or computer simulation of the effects (Klosko et al., 2000). And, as the equipment used is very inexpensive, the experiment is well within the means of almost any school system. References Carey, S., R. Evans, M. Honda, E. Jay, C. Unger, 1989, ``An experiment is when you try it and see if it works'': A study of grade 7 students' understanding of the construction of knowledge, International Journal of Science Education, 11, 514-529 DeLaughter, J., S. Stein, C. Stein, K. R. Bain, 1998, Preconceptions abound among students in an introductory earth science course, EOS, 79, 429+432 Dominguez, S, J. Malavieille, S. Lallemand, 2000, Deformation of accretionary wedges in response to seamount subduction: Insights from sandbox experiments, Tectonics, 19(1), 182-196 Herbert, B., 2003, The role of scaffolding student metacognition in developing mental models of complex, Earth and environmental systems. DFG-NSF International Workshops on Research and Development in Mathematics and Science Education, November 19-21, 2003, Washington D.C. http://geoexplorer.tamu.edu/dfgnsf/WG1.html Horsfield, W.T., 1977, An experimental approach to basement controlled faulting, Geologie en Mijnbouw, 56, 363-370 Klosko, E., J. DeLaughter, S. Stein, 2000, Technology in introductory geophysics: the high - low mix, Computers & Geosciences, 26(6), 693-698

  9. From the coupling between ion beam analysis techniques and physico-chemical characterization methods to the study of irradiation effects on materials behaviour; Du couplage des techniques d'analyse par faisceaux d'ions et des methodes de caracterisation physico-chimique a l'etude des effets d'irradiation sur le comportement des materiaux

    Energy Technology Data Exchange (ETDEWEB)

    Millard-Pinard, N

    2003-07-01

    The general purpose of my research work is to follow and to interpret the surface evolution of materials, which have received several treatments. During my PhD and my post-doc work, my field of research was tribology. Since I arrived in the 'Aval du Cycle Electronucleaire' group of the Institut de Physique Nucleaire de Lyon, my research activities are in line with the CNRS program 'PACE ' (Programme sur l'Aval du Cycle Electronucleaire) within the ACTINET network. They are coordinated by the PARIS (Physico-chimie des actinides et autres radioelements en solution et aux interfaces) and NOMADE (NOuveaux MAteriaux pour les DEchets) GDR with ANDRA (Agence Nationale pour la gestion des Dechets RAdioactifs), EDF and IRSN (Institut de Radioprotection et de Surete Nucleaire) as partner organisations. My work focused on the study of fission products and actinides migration in barrier materials, which may be capable of assuring the long term safety of deep geological repositories. Until now, it was necessary to use the coupling of ion beam analysis techniques and physico-chemical characterization techniques. During the last few months, I have became interested in understanding radiolytic effects. This new orientation has led us to use ion beams as an irradiating tool. These irradiation experiments are pursued in three major projects. The study of cobalt sulfide inhibition effects of radiolysis gas production during the irradiation of model organic molecules. This is a collaboration with the IRSN, the Institut de Recherche sur la Catalyse and the Ecole Nationale Superieure des Mines de Saint-Etienne. A PhD, co-directed by M. Pijolat from ENSMSE and myself, concerning this study will start in October 2003. Water radiolysis effects on iron corrosion are also studied in the particular case of vitrified nuclear waste containers, which will be stored in deep geological repositories. One ANDRA financed PhD, co-directed by Nathalie Moncoffre and myself, is

  10. Le recours aux modeles dans l'enseignement de la biologie au secondaire : Conceptions d'enseignantes et d'enseignants et modes d'utilisation

    Science.gov (United States)

    Varlet, Madeleine

    Le recours aux modeles et a la modelisation est mentionne dans la documentation scientifique comme un moyen de favoriser la mise en oeuvre de pratiques d'enseignement-apprentissage constructivistes pour pallier les difficultes d'apprentissage en sciences. L'etude prealable du rapport des enseignantes et des enseignants aux modeles et a la modelisation est alors pertinente pour comprendre leurs pratiques d'enseignement et identifier des elements dont la prise en compte dans les formations initiale et disciplinaire peut contribuer au developpement d'un enseignement constructiviste des sciences. Plusieurs recherches ont porte sur ces conceptions sans faire de distinction selon les matieres enseignees, telles la physique, la chimie ou la biologie, alors que les modeles ne sont pas forcement utilises ou compris de la meme maniere dans ces differentes disciplines. Notre recherche s'est interessee aux conceptions d'enseignantes et d'enseignants de biologie au secondaire au sujet des modeles scientifiques, de quelques formes de representations de ces modeles ainsi que de leurs modes d'utilisation en classe. Les resultats, que nous avons obtenus au moyen d'une serie d'entrevues semi-dirigees, indiquent que globalement leurs conceptions au sujet des modeles sont compatibles avec celle scientifiquement admise, mais varient quant aux formes de representations des modeles. L'examen de ces conceptions temoigne d'une connaissance limitee des modeles et variable selon la matiere enseignee. Le niveau d'etudes, la formation prealable, l'experience en enseignement et un possible cloisonnement des matieres pourraient expliquer les differentes conceptions identifiees. En outre, des difficultes temporelles, conceptuelles et techniques peuvent freiner leurs tentatives de modelisation avec les eleves. Toutefois, nos resultats accreditent l'hypothese que les conceptions des enseignantes et des enseignants eux-memes au sujet des modeles, de leurs formes de representation et de leur approche

  11. Le programme Génoplante, programme mobilisateur en génomique végétale

    Directory of Open Access Journals (Sweden)

    Caboche Michel

    2002-03-01

    Full Text Available Les enjeux de la génomique végétale sont immenses pour le secteur de la création variétale et concernent de multiples objectifs, allant de la réduction d’intrants à l’amélioration de la qualité des produits récoltés ou transformés. Une situation d’oligopole se met en place au niveau mondial avec quelques firmes provenant du secteur de la chimie, principalement aux États-Unis avec de très forts soutiens publics. En 1998, l’Inra, le CNRS, le Cirad, l’IRD pour le secteur public et Biogemma, Aventis Crop Ssciences et Bioplante pour le secteur privé s’engagent dans le programme Génoplante, acté, en février 1999, par le ministère de la Recherche, qui y apporte son soutien, pour une première période de cinq ans, afin de permettre à nos recherches, fondamentale et appliquée en biologie végétale, de rester compétitives. Le programme Génoplante comprend d’abord des programmes génériques : analyse fonctionnelle du génome d’Arabidopsis, génomique du riz, nouveaux outils d’analyse des génomes, bio-informatique, cibles importantes dans le génome des plantes cultivées. L’évaluation des projets soumis dans ce cadre est réalisée par des experts internationaux indépendants. Globalement, plus de 300 chercheurs sont impliqués dans ces projets. Il comprend aussi des programmes par espèces (blé, maïs, colza, tournesol, pois ayant chacun une partie générique (cartographie physique, banques génomiques, etc. et des projets concernant des caractères agronomiques, des stratégies de résistance aux maladies, ou des objectifs de caractérisation et d’amélioration de la qualité des produits.

  12. The importance of using dynamical a-priori profiles for infrared O3 retrievals : the case of IASI.

    Science.gov (United States)

    Peiro, H.; Emili, E.; Le Flochmoen, E.; Barret, B.; Cariolle, D.

    2016-12-01

    Tropospheric ozone (O3) is a trace gas involved in the global greenhouse effect. To quantify its contribution to global warming, an accurate determination of O3 profiles is necessary. The instrument IASI (Infrared Atmospheric Sounding Interferometer), on board satellite MetOP-A, is the more sensitive sensor to tropospheric O3 with a high spatio-temporal coverage. Satellite retrievals are often based on the inversion of the measured radiance data with a variational approach. This requires an a priori profile and the correspondent error covariance matrix (COV) as ancillary input. Previous studies have shown some biases ( 20%) in IASI retrievals for tropospheric column in the Southern Hemisphere (SH). A possible source of errors is caused by the a priori profile. This study aims to i) build a dynamical a priori profile O3 with a Chemistry Transport Model (CTM), ii) integrate and to demonstrate the interest of this a priori profile in IASI retrievals.Global O3 profiles are retrieved from IASI radiances with the SOFRID (Software for a fast Retrieval of IASI Data) algorithm. It is based on the RTTOV (Radiative Transfer for TOVS) code and a 1D-Var retrieval scheme. Until now, a constant a priori profile was based on a combination of MOZAIC, WOUDC-SHADOZ and Aura/MLS data named here CLIM PR. The global CTM MOCAGE (Modèle de Chimie Atmosphérique à Grande Echelle) has been used with a linear O3 chemistry scheme to assimilate Microwave Limb Sounder (MLS) data. The model resolution of 2°x2°, with 60 sigma-hybrid vertical levels covering the stratosphere has been used. MLS level 2 products have been assimilated with a 4D-VAR variational algorithm to constrain stratospheric O3 and obtain high quality a priori profiles O3 above the tropopause. From this reanalysis, we built these profiles at a 6h frequency on a coarser resolution grid 10°x20° named MOCAGE+MLS PR.Statistical comparisons between retrievals and ozonesondes have shown better correlations and smaller biases for

  13. Towards the development of a novel bioinspired functional material: Synthesis and characterization of hybrid TiO{sub 2}/DHICA-melanin nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Pezzella, Alessandro; Capelli, Luigia [Dept. of Chemical Sciences, Via Cintia 4, 80126 Napoli (Italy); Costantini, Aniello [Dept. of Materials and Production Engineering, Piazzale Tecchio 80, 80125 Napoli (Italy); Luciani, Giuseppina, E-mail: luciani@unina.it [Dept. of Materials and Production Engineering, Piazzale Tecchio 80, 80125 Napoli (Italy); Tescione, Fabiana; Silvestri, Brigida [Dept. of Materials and Production Engineering, Piazzale Tecchio 80, 80125 Napoli (Italy); Vitiello, Giuseppe [Dept. of Chemical Sciences, Via Cintia 4, 80126 Napoli (Italy); Branda, Francesco [Dept. of Materials and Production Engineering, Piazzale Tecchio 80, 80125 Napoli (Italy)

    2013-01-01

    A large number of recent literature data focus on modification/modulation of surface chemistry of inorganic materials in order to improve their functional properties. Melanins, a wide class of natural pigments, are recently emerging as a powerful organic component for developing bioinspired active material for a large number of applications from organoelectronics to bioactive compounds. Here we report the use of the approach referred as 'chimie douce', involving in situ formation of the hybrids through reactions of precursors under mild conditions, to prepare novel hybrid functional architectures based on eumelanin like 5,6 dihydroxyindole-2-carboxylic acid (DHICA) polymer and TiO{sub 2}. Two synthesis procedures were carried out to get DHICA-melanin coated TiO{sub 2} nanoparticles as well as mixed DHICA/TiO{sub 2} hybrid nanostructures. Such systems were characterized through EPR, FT-IR and fluorescence spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD), and TEM microscopy in order to assess the effect of synthesis path as well as of DHICA content on structural, morphological and optical properties of TiO{sub 2} nanostructures. In particular, EPR, FT-IR spectra and TGA analysis confirmed the presence of DHICA-melanin in these samples. TEM measurements indicated the formation of the nanoparticles having relatively narrow size distribution with average particle size of about 10 nm. DHICA-melanin does act as a morphological agent affecting morphology of hybrid nanostructures. XRD analysis proved that TiO{sub 2} hybrid nanoparticles kept anatase structures for DHICA-melanin contents within the range of investigated compositions, i.e. up to 50% wt/wt. - Highlights: Black-Right-Pointing-Pointer TiO{sub 2}/DHICA melanin blends are novel hybrid functional architectures. Black-Right-Pointing-Pointer Two synthetic approaches were explored to produce TiO{sub 2}/DHICA nanostructures. Black-Right-Pointing-Pointer TiO{sub 2} nanorods prepared

  14. Aerosol data assimilation in the chemical transport model MOCAGE during the TRAQA/ChArMEx campaign: aerosol optical depth

    Science.gov (United States)

    Sič, Bojan; El Amraoui, Laaziz; Piacentini, Andrea; Marécal, Virginie; Emili, Emanuele; Cariolle, Daniel; Prather, Michael; Attié, Jean-Luc

    2016-11-01

    In this study, we describe the development of the aerosol optical depth (AOD) assimilation module in the chemistry transport model (CTM) MOCAGE (Modèle de Chimie Atmosphérique à Grande Echelle). Our goal is to assimilate the spatially averaged 2-D column AOD data from the National Aeronautics and Space Administration (NASA) Moderate-resolution Imaging Spectroradiometer (MODIS) instrument, and to estimate improvements in a 3-D CTM assimilation run compared to a direct model run. Our assimilation system uses 3-D-FGAT (first guess at appropriate time) as an assimilation method and the total 3-D aerosol concentration as a control variable. In order to have an extensive validation dataset, we carried out our experiment in the northern summer of 2012 when the pre-ChArMEx (CHemistry and AeRosol MEditerranean EXperiment) field campaign TRAQA (TRAnsport à longue distance et Qualité de l'Air dans le bassin méditerranéen) took place in the western Mediterranean basin. The assimilated model run is evaluated independently against a range of aerosol properties (2-D and 3-D) measured by in situ instruments (the TRAQA size-resolved balloon and aircraft measurements), the satellite Spinning Enhanced Visible and InfraRed Imager (SEVIRI) instrument and ground-based instruments from the Aerosol Robotic Network (AERONET) network. The evaluation demonstrates that the AOD assimilation greatly improves aerosol representation in the model. For example, the comparison of the direct and the assimilated model run with AERONET data shows that the assimilation increased the correlation (from 0.74 to 0.88), and reduced the bias (from 0.050 to 0.006) and the root mean square error in the AOD (from 0.12 to 0.07). When compared to the 3-D concentration data obtained by the in situ aircraft and balloon measurements, the assimilation consistently improves the model output. The best results as expected occur when the shape of the vertical profile is correctly simulated by the direct model. We

  15. Atmospheric anthropic impacts tracked by the French atmospheric mobile observatory

    Science.gov (United States)

    Cuesta, J.; Chazette, P.; Flamant, P. H.

    2009-04-01

    A new ATmospheric Mobile ObServatory, so called "ATMOS", has been developed by the LiMAG "Lidar, Meteorology and Geophysics" team of the Institut Pierre Simon Laplace (IPSL) in France, in order to contribute to international field campaigns for studying atmospheric physico-chemistry, air quality and climate (i.e. aerosols, clouds, trace gazes, atmospheric dynamics and energy budget) and the ground-based validation of satellite observations. ATMOS has been deployed in the framework of i) LISAIR, for monitoring air quality in Paris in 2005, ii) AMMA "African Monsoon Multidisciplinary Analysis", in Tamanrasset and in Niamey for observing the aerosols and the atmospheric boundary layer in the Sahara and in the Sahel in 2006, iii) COPS "Convectively and Orographycally driven Precipitation Study" in the Rhin Valley in 2007 and iv) the validation of the spatial mission CALIPSO, launched in April 2006. In the coming years, ATMOS will be deployed i) in the Paris Megacity, in the framework of MEGAPOLI (2009-2010), ii) in southern France (near Marseille) for the Chemistry-Aerosol Mediterranean Experiment CHARMEX (2011-2012) and iii) the validation of ADM-Aeolus in 2010-2011 and Earth-Care in 2012. ATMOS payload is modular, accounting for the different platforms, instruments and measuring techniques. The deployment of ATMOS is an essential contribution to field campaigns, complementing the fixed sites, and a potential alternative of airborne platforms, heavier and more expensive. ATMOS mobile payload comprises both the remote sensing platform MOBILIS ("Moyens mOBIles de téLédetection de l'IPSL") and the in-situ physico-chemical station SAMMO ("Station Aérosols et chiMie MObile"). MOBILIS is an autonomous and high-performance system constituted by a full set of active and passive remote sensing instrumentation (i.e. Lidars and radiometers), whose payload may be adapted for either i) long term fixed monitoring in a maritime container or a shelter, ii) ground-based transect

  16. Combined assimilation of IASI and MLS observations to constrain tropospheric and stratospheric ozone in a global chemical transport model

    Directory of Open Access Journals (Sweden)

    E. Emili

    2013-08-01

    Full Text Available Accurate and temporally resolved fields of free-troposphere ozone are of major importance to quantify the intercontinental transport of pollution and the ozone radiative forcing. In this study we examine the impact of assimilating ozone observations from the Microwave Limb Sounder (MLS and the Infrared Atmospheric Sounding Interferometer (IASI in a global chemical transport model (MOdèle de Chimie Atmosphérique à Grande Échelle, MOCAGE. The assimilation of the two instruments is performed by means of a variational algorithm (4-D-VAR and allows to constrain stratospheric and tropospheric ozone simultaneously. The analysis is first computed for the months of August and November 2008 and validated against ozone-sondes measurements to verify the presence of observations and model biases. It is found that the IASI Tropospheric Ozone Column (TOC, 1000–225 hPa should be bias-corrected prior to assimilation and MLS lowermost level (215 hPa excluded from the analysis. Furthermore, a longer analysis of 6 months (July–August 2008 showed that the combined assimilation of MLS and IASI is able to globally reduce the uncertainty (Root Mean Square Error, RMSE of the modeled ozone columns from 30% to 15% in the Upper-Troposphere/Lower-Stratosphere (UTLS, 70–225 hPa and from 25% to 20% in the free troposphere. The positive effect of assimilating IASI tropospheric observations is very significant at low latitudes (30° S–30° N, whereas it is not demonstrated at higher latitudes. Results are confirmed by a comparison with additional ozone datasets like the Measurements of OZone and wAter vapour by aIrbus in-service airCraft (MOZAIC data, the Ozone Monitoring Instrument (OMI total ozone columns and several high-altitude surface measurements. Finally, the analysis is found to be little sensitive to the assimilation parameters and the model chemical scheme, due to the high frequency of satellite observations compared to the average life-time of free

  17. Pharmacological targeting of β-adrenergic receptor functions abrogates NF-κB signaling and MMP-9 secretion in medulloblastoma cells

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    Borhane Annabi

    2010-11-01

    Full Text Available Borhane Annabi1,*, Eric Vaillancourt-Jean1,*, Alexander G Weil3, Richard Béliveau2,31Laboratoire d’Oncologie Moléculaire, Département de Chimie, Centre de Recherche BioMED, 2Laboratory of Molecular Medicine, Université du Québec à Montréal, Quebec, Canada; 3Department of Neurosurgery, CHUM Notre Dame, Montreal, Quebec, Canada; *These authors contributed equally to this workAbstract: Targeting of the vascular endothelium compartment explains, in part, the therapeutic efficacy of the nonselective β-adrenergic antagonist propranolol against common endothelial tumors such as hemangiomas. In vitro, the antiangiogenic biological activity of propranolol was shown to inhibit human brain microvascular endothelial cell tubulogenesis. However, possible interference of propranolol with cell signaling associated with the tumoral compartment remains unexplored. We therefore assessed the potency of propranolol against a pediatric brain tumor-derived DAOY medulloblastoma cell model. Gene expression of β1-, β2-, and β3-adrenergic receptors was confirmed in DAOY cells by semiquantitative RT-PCR. We next found that propranolol dose-dependently inhibited induction of the key extracellular matrix-degrading and blood–brain barrier disrupting enzyme matrix metalloproteinase-9 (MMP-9 by phorbol 12-myristate 13-acetate (PMA. Propranolol not only inhibited PMA-induced phosphorylation of the extracellular signal-regulated kinase (Erk, but also that of IkappaB (IκB, preventing the IκB phosphorylation which is a prerequisite for IκB degradation. Propranolol inhibition of IκB phosphorylation was shown to occur with optimal efficacy at 30 µM. Although propranolol, at up to 100 µM, did not affect cell viability, it potentiated PMA-mediated signaling that ultimately led to diminished phosphorylation of Akt. The anti-Erk and anti-Akt phosphorylation effects are both suggestive of antiproliferative and antisurvival signaling, respectively. Our data are

  18. Transcriptional targeting of sphingosine-1- phosphate receptor S1P2 by epigallocatechin- 3-gallate prevents sphingosine-1-phosphate- mediated signaling in macrophage-differentiated HL-60 promyelomonocytic leukemia cells

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    Chokor R

    2014-05-01

    Full Text Available Rima Chokor, Sylvie Lamy, Borhane AnnabiLaboratoire d'Oncologie Moléculaire, Centre de recherche BIOMED, Département de Chimie, Université du Québec à Montréal, Montreal, QC, CanadaBackground: Macrophage chemotaxis followed by blood–brain barrier transendothelial migration is believed to be associated with inflammation in the central nervous system. Antineuroinflammatory strategies have identified the dietary-derived epigallocatechin-3-gallate (EGCG as an efficient agent to prevent neuroinflammation-associated neurodegenerative diseases by targeting proinflammatory mediator signaling.Methods: Given that high levels of sphingosine kinase and its product, sphingosine-1-phosphate (S1P, are present in brain tumors, we used quantitative reverse-transcription polymerase chain reaction (qRT-PCR and immunoblotting to test whether EGCG may impact on S1P receptor gene expression and prevent S1P response in undifferentiated and in terminally differentiated macrophages.Results: Promyelomonocytic human leukemia (HL-60 cells were differentiated into macrophages, and S1P triggered phosphorylation in extracellular signal-regulated kinase (ERK, c-Jun N-terminal kinase (JNK, and P38 mitogen-activated protein kinase (MAPK intracellular signaling, as shown by Western blot analysis. Pretreatment of cells with EGCG prior to differentiation inhibited the response to S1P in all three pathways, while EGCG abrogated P38 MAPK phosphorylation when present only during differentiation. Terminally-differentiated macrophages were, however, insensitive to EGCG treatment. Using qRT-PCR, gene expression of the S1P receptors S1P1, S1P2, and S1P5 was predominantly induced in terminally-differentiated macrophages, while the S1P2 was decreased by EGCG treatment.Conclusion: Our data suggest that diet-derived EGCG achieves efficient effects as a preventive agent, targeting signaling pathways prior to cell terminal differentiation. Such properties could impact on cell chemotaxis

  19. L'art de la teinture à l'Académie royale des sciences au XVIIIe siècle

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    Christine Lehman

    2012-03-01

    Full Text Available Quand Colbert fonda l’Académie des sciences dans le but de dynamiser l’industrie, aucun chimiste de l’Académie n’était encore susceptible de rationaliser l’art très empirique de la teinture. Au XVIIe siècle, la teinture n’était pas un sujet traité lors des séances de l’Académie, en revanche l’intérêt des académiciens pour cet art chimique a pris de l’ampleur dans les années 1750 sous l’impulsion de Pierre-Joseph Macquer et du Bureau du Commerce. Dans cet article, la présentation de l’art de la teinture à l’Académie des sciences au XVIIIe siècle est centrée principalement sur les premiers travaux académiques sur la teinture, sur les mémoires de Macquer, ainsi que sur les prix et les publications sur la teinture proposés par l’Académie.Au cours du XVIIIe siècle, la teinture abandonnera le monde des artisans teinturiers pour intéresser le monde savant et les académiciens. La teinture acquerra ses lettres de noblesse, sortant des ateliers pour entrer à l’Académie avant de s’enseigner comme la chimie.When Colbert founded the Académie des sciences his target was to stimulate industry. But at that time no chemist in the Académie was yet in a position to rationalise the very empirical art of dyeing. During the 17th century dyeing was not discussed in the sessions of the Académie. By contrast the academicians’ interest for this chemical art increased in the course of years 1750 under the impulse of Pierre-Joseph Macquer and the Bureau du Commerce. This paper presents the art of dyeing by focussing mainly on the first academic works on dyeing, on Macquer’s memoirs and on the prizes and publications on dyeing proposed by the Académie. During the 18th century dyeing gradually left the world of craftsmen dyers to catch the interest of the world of scientists and academicians. Dyeing won its lettres de noblesse, springing from workshops to enter the Académie and be finally taught like chemistry.

  20. L’olivier au Maroc

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    El Mouhtadi Issam

    2014-03-01

    Full Text Available L’olivier est une culture traditionnelle sur le pourtour de la Méditerranée. Il est donc naturel de trouver cet arbre au Maroc où il est présent depuis des siècles. Cultivé surtout traditionnellement jusqu’à ses dernières années, il fait l’objet maintenant d’un plan de valorisation très ambitieux pour non seulement garder le Royaume à son niveau actuel (2e producteur mondial pour l’olive de conserve et 6e pour l’huile d’olive mais pour conquérir de nouveaux marchés au niveau mondial et profiter ainsi de l’engouement que connaît cette huile reconnue pour ses bienfaits. Le plan national « Maroc Vert » permet ainsi, grâce à des subventions conséquentes, non seulement de renouveler les vergers existant avec la variété traditionnelle picholine du Maroc, mais également la plantation de nouvelles variétés en super-intensif dans le but d’industrialiser au maximum de nouveaux vergers. Il en est de même pour la transformation des olives en huile de bonne qualité avec la mise en place d’unités de trituration modernes qui doivent supplanter à terme la multitude de « maâsra » et réduire ainsi l’impact environnemental dû aux margines. L’olive ne sera plus dans l’avenir que représentée par son huile et ses formes comestibles, mais les résidus de son extraction seront valorisés soit sous forme de combustible élaboré pour le grignon, soit sous forme d’une base de chimie verte pour les sous-produits du raffinage. D’autres applications sont actuellement à l’étude, car le Maroc à compris, comme tous les autres grands pays producteurs, que l’olive était un nouveau gisement de richesses.

  1. Lipochimie et innovations

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    Alfos Carine

    2003-09-01

    Full Text Available Peut-on parler d’un nouvel âge d’or pour les produits à base de ressources végétales renouvelables et notamment pour les huiles ? Porteurs de performances spécifiques et de caractéristiques plus écologiquement correctes, leur emploi ouvre à l’industrie un potentiel d’innovations auquel participe le département de chimie et rhéologie de l’Iterg. La prise de conscience collective, associée aux évolutions des réglementations françaises et européennes, devrait conduire les industries à prendre de plus en plus en compte le respect de l’environnement dans leurs activités. La substitution de dérivés pétrochimiques par des produits d’origine agricole dans certains secteurs industriels (détergence, lubrifiants, solvants notamment contribue à la protection de notre environnement : diminution des volumes de déchets et des effluents, lutte contre l’effet de serre, moindre écotoxicité, innocuité pour la santé. De plus, l’épuisement latent des ressources pétrolières et la pratique de la jachère ont permis d’accélérer le développement de nouvelles voies de valorisations des huiles végétales et plus largement des agroressources. Les enjeux, à l’horizon 2010, sont bien plus importants encore pour ces produits, qui de part leur fonctionnalité spécifique, ont vocation à continuer d’occuper des marchés de niche. D’ici 10 ans, 2 à 3 millions d’hectares pourraient être consacrés à l’industrie du végétal \\; il s’agit là d’une véritable stratégie de développement durable qui nécessite un soutien politique, une vision à long terme et une motivation forte de l’industrie.

  2. Conception et caracterisation d'un magnetoplasma produit par une onde de surface pour la pulverisation d'echantillons solides

    Science.gov (United States)

    Masse, Louis Philippe

    Suite a l'extraordinaire explosion de l'informatique de la derniere decennie, la science et la technologie des materiaux ont pris un essor extraordinaire. Par exemple, il est devenu crucial de concevoir des materiaux a haut degre de purete. Ce besoin a fortement motive le developpement de methodes d'analyse de solides. Traditionnellement, la methode adoptee est l'analyse par torche ICP, mais pour de nombreuses raisons, dont la lenteur de cette methode, la communaute scientifique oeuvrant en chimie analytique recherche des techniques d'analyse de solides directes, rapides et plus sensibles. Parmi les voies possibles, on trouve les methodes basees sur la pulverisation par plasma. Dans ce contexte, nous avons etudie la possibilite et la pertinence d'utiliser un magnetoplasma entretenu par une onde de surface pour pulveriser des solides dans le but de les analyser. Nos travaux portent principalement sur l'etude du comportement du plasma lors de la pulverisation. Nous avons montre que la pulverisation affecte la decharge de diverses facons. En premier lieu, la concentration d'especes provenant du materiau pulverise dans le plasma augmente avec la tension de polarisation. De plus, la concentration d'especes pulverisees diminue lorsque la pression croit, possiblement a cause du redepot. Nous avons aussi montre qu'il etait possible de pulveriser des solides isolants en exploitant le phenomene d'autopolarisation du a l'application d'une tension RF. Nous avons aussi etudie l'effet de la pulverisation sur la temperature et la densite electronique. Ainsi, lors de la pulverisation de metaux tels que le cuivre, la temperature electronique diminue lorsque la tension de polarisation augmente. Ceci est attribuable a l'augmentation de la densite d'especes metalliques neutres facilement ionisables par impact electronique. Nous avons aussi note que la densite electronique augmente avec la concentration d'especes metalliques dans le plasma, ce qui resulte d'un meilleur bilan de

  3. ICOM2012: 3rd International Conference on the Physics of Optical Materials and Devices (Belgrade, Serbia, 2-6 September 2012)

    Science.gov (United States)

    Dramićanin, Miroslav D.; Antić, Željka; Viana, Bruno

    2013-11-01

    The 3rd International Conference on the Physics of Optical Materials and Devices (ICOM2012) was held in Belgrade (Serbia) from 2 to 6 September 2012 (figure 1). The conference was organized by the Vinča Institute of Nuclear Sciences, University of Belgrade (Serbia) and the Laboratoire de Chimie de la Matière Condensée de Paris (France), and supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia and Optical Society of America. ICOM2012 was a follow-up to the two previous, successful ICOM conferences held in Herceg Novi in 2006 and 2009. The conference aimed at providing a forum for scientists in optical materials to debate on: • Luminescent materials and nanomaterials • Hybrid optical materials (organic/inorganic) • Characterization techniques of optical materials • Luminescence mechanisms and energy transfers • Theory and modeling of optical processes • Ultrafast-laser processing of materials • Optical sensors • Medical imaging • Advanced optical materials in photovoltaics and biophotonics • Photothermal and photoacoustic spectroscopy and phenomena The conference stressed the value of a fundamental scientific understanding of optical materials. A particular accent was put on wide band-gap materials in crystalline, glass and nanocrystalline forms. The applications mainly involved lasers, scintillators and phosphors. Rare earth and transition metal ions introduced as dopants in various hosts were considered, and their impact on the optical properties were detailed in several presentations. This volume contains selected contributions of speakers and participants of the ICOM2012 conference. The conference provided a unique opportunity for about 200 scientists from 32 countries to discuss recent progress in the field of optical materials. During the three and half days, 21 invited talks and 52 contributed lectures were given, with a special event in memory of our dear colleague Professor Dr Tsoltan

  4. PREFACE: XV International Seminar on Physics and Chemistry of Solids

    Science.gov (United States)

    Kotur, Bogdan; Brągiel, Piotr

    2011-03-01

                      Logo     Logo The XV International Seminar on Physics and Chemistry of Solids (ISPCS15) was held from 7-10 June 2009 in Szklarska Poręba. Over eighty participants joined together in this mountain resort, at the foot of Szrenica peak, in the Polish part of the Sudety range. The majority or participants, in accordance with Seminar tradition, were from Ukraine and Poland. The pleasant and warm atmosphere created by the organizers was conducive to fruitful discussions, making new contacts and to joyful gatherings with friends. Even the rainy weather could not change that. Lectures and communications mainly covered the fields of solid state physics and chemistry, and possible applications. This time, however, a new section was introduced - one devoted to modern topics in liquid chemistry. Sometimes such a look over the borders of scientific specialties leads to interesting insights and original research solutions. Some of the papers presented during ISPCS15 are collected in this volume. Their diversity is representative of both the scope and character of this Seminar. The majority of the papers are research reports, but a review article and a paper focussed on problems connected with environmental protection are also included. This Conference has functioned for over a decade due to the permanent support of the rectors of both co-organizing universities: Professor Ivan Vakarchuk from Ivan Franko National University of Lviv and Professor Zygmunt Bąk from Jan Dlugosz University in Częstochowa. It is our pleasure, on behalf of the all participants of the past Seminars, to express our gratitude for this assistance. We would also like to thank all the invited speakers who kindly accepted our invitation, namely Professors Roman Gladyshevskii (Ivan Franko National University, Lviv, Ukraine), Mihaela Gulea (Laboratoire de Chimie Moleculare et Thioorganique, CAEN, France), Osama I Abd El-Salam (National Research

  5. Aerosol Plume during a Polluted Event Occuring Over Paris Area and its Potential Photochemical Effect

    Science.gov (United States)

    Randriamiarisoa, H.; Chazette, P.; Sanak, J.; Hauglustaine, D.

    2002-12-01

    As in many big cities, there are several pollution events in Paris area. A thorough understanding of the processes leading on the formation of pollutants and their transport during pollution episodes is necessary. One of the pertinent factors, which contributions on atmospheric chemistry and radiative effect are not yet well known, is the aerosol. ESQUIF (Etude et Simulation de la QUalité de l?air en Ile de France) is the first program dedicated to study such issues over the Paris area. It was carried out from summer 1998 to winter 2000 (Menut et al., 2000). To characterize all the properties of the urban aerosol, many campaigns were coordinated using both ground and airborne measurements (Chazette et al., 2000). We are focusing on the 31st of July 2000 where a well-defined polluted plume has been observed. Aerosol number concentrations in different size classes were measured and show that urban aerosol in Paris area is mainly submicronic. The absorbent part of the aerosol, mainly associated to the black carbon component, has been observed to be associated to particles with diameter less than 0.1 æm. The single scattering albedo has been assessed to be close to 0.85 leading to a significant influence on the photochemical chemistry. Indeed, a significant decrease of the daily maximum ozone concentration has been calculated using the INCA model and will be presented. ACKNOWLEDGEMENTS The Programme National de Chimie Atmosphérique, INSU supported this work. REFERENCES Chazette P., H. Randriamiarisoa, J. Sanak, C. Flamant, J. Pelon, M. Sicard, H. Cachier, F. Aulagnier, R. Sarda-Esteve, L. Gomes, S. Alfaro and A. Gaudichet (2001). ESQUIF 2000 : Aerosol survey over the Ile-de-France area, J. Aerosol Sci ., 32/suppl. 1, S439-S440. Menut, L., R. Vautard, C. Flamant, A. Abonnel, M. Beekmann, P. Chazette, P.H. Flamant, D. Gombert, D. Guédalia, D. Kley, M.P. Lefebvre, B. Lossec, D. Martin, G. Mégie, P. Perros, M. Sicard and G. Toupance (2000). Measurements and modelling

  6. 维吾尔文Bigram文本特征提取%Bigram feature extraction for Uyghur text

    Institute of Scientific and Technical Information of China (English)

    阿力木江·艾沙; 库尔班·吾布力; 吐尔根·依布拉音

    2015-01-01

    Text representation is the most important phase in automatic text categorization. In the vector space model based text representation, the selection of feature granularity has the direct impact on the text categorization performance. The word features don’t have the good representative power to represent the Uyghur texts in text categorization. To solve this problem, the CHIMI based Uyghur Bigram extraction method is proposed and the Uyghur text categorization experi-ments are conducted using support vector machine algorithm based on the extracted Bigrams as text features. The experi-mental results show that the Bigram based Uyghur text categorization achieves higher classification precision and recall compared to the word based categorization and experiments demonstrate the effectiveness of the proposed algorithm.%文本特征表示是在文本自动分类中最重要的一个环节。在基于向量空间模型(VSM)的文本表示中特征单元粒度的选择直接影响到文本分类的效果。在维吾尔文文本分类中,对于单词特征不能更好地表征文本内容特征的问题,在分析了维吾尔文Bigram对文本分类作用的基础上,构造了一个新的统计量CHIMI,并在此基础上提出了一种维吾尔语Bigram特征提取算法。将抽取到的Bigram作为文本特征,采用支持向量机(SVM)算法对维吾尔文文本进行了分类实验。实验结果表明,与以词为特征的文本分类相比,Bigram作为文本特征能够提高维吾尔文文本分类的准确率和召回率并且通过实验验证了该算法的有效性。

  7. Diffusion, diffraction des neutrons en temps réel et études réalisées in situ

    Science.gov (United States)

    Isnard, O.

    2003-02-01

    La diffusion des neutrons est une technique particulièrement efficace pour l'analyse en temps réel des processus réactionnels dans la matière. La diffraction de neutrons in situ a été développée très tôt sur les sources à haut flux tel que l'Institut Laue Langevin. Ces études nécessitent un flux de neutrons important et un détecteur couvrant un domaine angulaire le plus grand possible. Les neutrons offrent la spécificité d'être très peu absorbés par nombre de matériaux, cette faible absorption fait de la diffusion neutronique un excellent outil pour sonder la matière en volume et de manière non destructive. Cela permet en particulier d'utiliser des environnements d'échantillons complexes tout en conservant un flux raisonnable. La diffusion de neutrons en temps réel est donc très largement utilisée par diverses communautés scientifiques : sciences des matériaux, physiciens, chimistes... L'objet de ce cours est de donner les paramètres importants pour ce type d'étude et d'illustrer le propos à l'aide d'exemples pris dans des domaines scientifiques divers : électrochimie, magnétisme, métallurgie, chimie du solide. Après avoir présenté quelques repères méthodologiques sur les méthodes d'acquisition de données, des exemples montreront le fort potentiel de la diffusion neutronique en temps réel pour l'étude de la matière dans des conditions dynamiques. Enfin, nous donnerons aussi quelques conseils pour la visualisation, le dépouillement et l'analyse de ce type d'expérience. La diffusion des neutrons sur poudre est actuellement très bien adaptée aux études réalisées in situ. Cependant, nous verrons que la faisabilité d'études in situ s'étend à d'autres techniques expérimentales telles que la diffusion des neutrons aux petits angles et même la diffusion sur monocristal qui est en plein renouveau.

  8. The First SeaWiFS HPLC Analysis Round-Robin Experiment (SeaHARRE-1)

    Science.gov (United States)

    Hooker, Stanford B. (Editor); Firestone, Elaine R. (Editor); Claustre, Herve; Ras, Josephine; VanHeukelem, Laurie; Berthon, Jean-Francois; Targa, Cristina; vanderLinde, Dirk; Barlow, Ray; Sessions, Heather

    2001-01-01

    Four laboratories, which had contributed to various aspects of SeaWiFS calibration and validation activities, participated in the first SeaWiFS HPLC Analysis Round-Robin Experiment (SeaHARRE-1): Horn Point Laboratory (USA), the Joint Research Centre (Italy), the Laboratoire de Physique et Chimie Marines (France), and the Marine and Coastal Management group (South Africa). The analyses of the data are presented in Chapter 1 and the individual methods of the four groups are presented in Chapters 2-5. The average (or overall) conclusions of the round-robin are derived from 12 in situ stations occupied during a cruise in the Mediterranean Sea, although, only 11 stations are used in the analyses. The data set is composed of 12 replicates taken during each sampling opportunity with 3 replicates going to each of the 4 laboratories. The average (or overall) results from the intercomparison of 15 pigments or pigment associations are as follows (in some cases, data subsets that exclude pigments which were not analyzed by all the laboratories, or that had unusually large variances, are used to exclude a variety of problematic pigments): a) the accuracy of the four methods in determining the concentration of total chlorophyll a is 7.9%, (one method did not separate mono- and divinyl chlorophyll a, and if the samples containing significant divinyl chlorophyll a concentrations are ignored, the four methods have an accuracy of 6.7%); b) the accuracy in determining the full set of pigments is 19.1%; c) there is a reduction in accuracy of approximately - 12.2% for every decade (factor of 10) decrease in concentration (based on a data subset); d) the precision of the four methods using a subset data is 8.617( 6.2% for an edited subset); e) the repeatability of the four methods using the subset data is 9.2% (7.2%; for an edited subset, and f) the reproducibility of the four methods using the subset data is 21.31% (15.0% for an edited subset).

  9. Pompes à chaleur dans l'industrie Heat Pumps in Industry

    Directory of Open Access Journals (Sweden)

    Benchecroun N.

    2006-11-01

    Full Text Available Les pompes à chaleur pourraient permettre une réduction de la consommation énergétique de l'industrie française estimée à 3,5 Mtep à l'horizon 1990 (300 000 tep en 1982. Ces installations se situeront dans les domaines du chauffage des locaux industriels, du séchage à basse température, du réchauffage de liquides et de certaines opérations de fractionnement. Pour les utilisations dans des procédés industriels les secteurs concernés sont principalement les industries agroalimentaires et, à plus long terme, celui de la chimie (y compris pétrochimie. On constate que les ventes de machines de forte puissance restent faibles (environ 500 de 1973 à 1982. Le climat général d'investissement, la nécessité d'adapter les procédés à l'utilisation d'une pompe à chaleur, et le faible niveau de température Heat pumps could be used to reduce energy consumption by French industry which may attain 3. 5 million tOE by 1990 (300 000 tOE in 1982. Such installations will be used in the fields of industrial space heating, low-temperature drying, the heating of liquids and various fractionating operations. For uses in industrial processes, the sectors involved are mainly agribusiness and food industries and, in the longer range, the chemical industry (including petrochemicals. Sales of high-powered machinery are still low (about 500 from 1973 to 1982. The general investment climate, the need to adapt processes to the use of heat pumps, and the low temperature level (< 120 °C of the heat delivered are the main factors holding back the penetration of this type of equipment in industry. The use of a nonazeotropic mixture of fluids (particularly hydrocarbons gives compression heat pumps a flexibility of adaptation which should help remove these technicalobstacles and thus make it easier for heat pumps to penetrate, especially in the chemical sector.

  10. Technical Note: Validation of Odin/SMR limb observations of ozone, comparisons with OSIRIS, POAM III, ground-based and balloon-borne instruments

    Directory of Open Access Journals (Sweden)

    F. Jégou

    2008-01-01

    Full Text Available The Odin satellite carries two instruments capable of determining stratospheric ozone profiles by limb sounding: the Sub-Millimetre Radiometer (SMR and the UV-visible spectrograph of the OSIRIS (Optical Spectrograph and InfraRed Imager System instrument. A large number of ozone profiles measurements were performed during six years from November 2001 to present. This ozone dataset is here used to make quantitative comparisons with satellite measurements in order to assess the quality of the Odin/SMR ozone measurements. In a first step, we compare Swedish SMR retrievals version 2.1, French SMR ozone retrievals version 222 (both from the 501.8 GHz band, and the OSIRIS retrievals version 3.0, with the operational version 4.0 ozone product from POAM III (Polar Ozone Atmospheric Measurement. In a second step, we refine the Odin/SMR validation by comparisons with ground-based instruments and balloon-borne observations. We use observations carried out within the framework of the Network for Detection of Atmospheric Composition Change (NDACC and balloon flight missions conducted by the Canadian Space Agency (CSA, the Laboratoire de Physique et de Chimie de l'Environnement (LPCE, Orléans, France, and the Service d'Aéronomie (SA, Paris, France. Coincidence criteria were 5° in latitude x in 10° longitude, and 5 h in time in Odin/POAM III comparisons, 12 h in Odin/NDACC comparisons, and 72 h in Odin/balloons comparisons. An agreement is found with the POAM III experiment (10–60 km within −0.3±0.2 ppmv (bias±standard deviation for SMR (v222, v2.1 and within −0.5±0.2 ppmv for OSIRIS (v3.0. Odin ozone mixing ratio products are systematically slightly lower than the POAM III data and show an ozone maximum lower by 1–5 km in altitude. The comparisons with the NDACC data (10–34 km for ozonesonde, 10–50 km for lidar, 10–60 for microwave instruments yield a good agreement within −0.15±0.3 ppmv for the SMR data and −0.3±0.3 ppmv

  11. Numerical and experimental study of the influence of the operational parameters on the formation mechanisms of oxides of nitrogen during the combustion of mixtures of cellulosic and plastic materials; Etude experimentale et numerique de l'influence des parametres operatoires sur les mecanismes de formation des oxydes d'azote lors de la combustion de melanges de materiaux cellulosiques et plastiques

    Energy Technology Data Exchange (ETDEWEB)

    Andzi Barhe, T.

    2004-10-15

    The current thesis was performed within a collaboration between the Laboratoire de Combustion et de Detonique (LCD of the University of Poitiers) and the Laboratoire de Physique et de Chimie d'Environnement (LPCE) of the University of Ouagadougou. It was financed by Agency for Environment and Energy Management (ADEME). The principle object of this study is the optimisation of the combustion process during the incineration of waste. This optimisation is aimed at the reduction of the polluting emissions, principally CO and NO, during the incineration of cellulosic and plastic materials. It involves the analysis of the influence of the operational parameters on the polluting emissions and the control of reaction mechanisms of formation and reduction of these pollutants during the combustion process. Consequently, the study was performed in two parts: an experimental part and a numerical part. The experimental part was realised using a fixed bed counterflow reactor. This setup simulates the combustion within an industrial waste incinerator. The reactor allows the combustion of a vertical layer of waste mixture (wood, cardboard, PET, polyamide) to be followed. Three model mixtures representative of the makeup of household waste were studied in order to determine the influence of the composition of the waste on the emission of pollutants (CO and NO). The obtained results show that this parameter has a practically negligible influence within the tested parameter range. Consequently the formation of pollutants depends on the operating parameters - the equivalence ratio and the temperature. A numerical study of the influence of these parameters in order to show their impact on the mechanisms of pollutant formation and to determine the chemical mechanisms involved in the formation of oxides of nitrogen. The numerical study was performed with software developed at the LCD. This programme based on a detailed chemical model coupled to a simple physical model. It uses the

  12. Le roi, l’armée et la science sous le règne de Carlos III

    Directory of Open Access Journals (Sweden)

    Jean-Paul Le Flem

    2011-08-01

    Full Text Available La deuxième moitié du xviiie siècle en Espagne, symbolisée par l’accession au trône de Carlos III en 1759, est marquée par un regain de l’esprit de modernité, le développement des techniques et de la recherche scientifique.Deux faits majeurs illustrent cet esprit nouveau. La réalisation du cadastre de la Ensenada, chef d’œuvre de la statistique dans la tradition retrouvée des grandes enquêtes de Philippe II, permet d’avoir une vision démographique mais aussi économique voire économétrique de la péninsule ibérique. D’autre part, à partir des années 1760, la fondation des cercles de la Société des Amis du Pays permet d’intéresser les élites locales au développement scientifique, à la recherche agronomique, aux techniques nouvelles dans tous les domaines voire à l’économétrie. De nombreux militaires proches du pouvoir participent à ces deux expériences. Au cœur même de l’institution militaire, surtout dans les armes dites « savantes » comme le génie, l’artillerie et particulièrement la marine, le goût pour la recherche et les nouvelles techniques se développe. Le roi, que la « novelleté » ne rebute pas, bien au contraire, surveille les institutions scientifiques, en crée de nouvelles et ne dédaigne pas de suivre de près certaines expériences comme la mesure du méridien terrestre en Équateur. Pour illustrer ce phénomène, nous avons choisi trois milieux militaires à la pointe de la recherche : - Les ingénieurs militaires. Issus pour la plupart de l’École de Bruxelles, ils ont les mêmes profils que ceux de leurs collègues français si bien analysés par Anne Blanchard. Ce ne sont pas seulement des techniciens de la fortification ou de la poliorcétique ; ils s’intéressent aussi aux techniques civiles : urbanisme, canaux de navigation et d’irrigation, botanique sans oublier la chimie et la métallurgie. Quelques-uns sont membres actifs des Sociétés des Amis du

  13. A new hydrogeological model of charging shallow and deep aquifers in the Lake Neusiedl - Seewinkel region (Northern Burgenland, Austria)

    Science.gov (United States)

    Häusler, Hermann; Müllegger, Christian; Körner, Wilfried; Ottner, Franz; Prohaska, Thomas; Irrgeher, Johanna; Tchaikovsky, Anastassiya; Dober, Gregor; Gritzmann, Romana; Mykhaylyuk, Ivanna

    2014-05-01

    .- Hydrogeology Journal, 19, 701-717. Tauber, A. F. (1965): Geologische Typologie und Genese der Mineralquellen und Mineralwässer im Neusiedlerseegebiet.- Wissenschaftliche Arbeiten aus dem Burgenland, 34, 259-304, 6 Tab., Eisenstadt. Wurm, M. (2000): Hydrogeochemische Methodik zur Klärung von Interaktionsprozessen von Formations-, Mineral-, Tiefengrund- und oberflächennahen Grundwässern im Einzugsgebiet des Neusiedlersees.- Unveröffentlichte Diplomarbeit, Institut für Geowissenschaften, Abteilung für Geologie und Lagerstättenlehre, Montanuniversität Leoben, 125 S., zahlr. Abb., Anhang (71 hydrochemische Analysen), Leoben.

  14. Genetic variety of sinkholes and their reconaissance and classification for the derivation of hazards and to forecast of collapses

    Science.gov (United States)

    Mucke, D.

    2012-04-01

    Genetic variety of sinkholes and their reconnaissance and classification for the derivation of hazards and to forecast of collapses Dieter Mucke GEOMONTAN Gesellschaft für Geologie und Bergbau mbH&Co.KG, Muldentalstrasse 56, 09603 Rothenfurth, Saxony/Germany The term "sinkhole" covers a lot of depressions on the earth's surface, caused by very different geological processes and anthropogenic activities. The speed of the origin of the depressions is different and leads to different hazards. The forecast look for hazards and the introduction of preventive measures gets safer if type and cause of the depressions are known of. First aim of the lecture is the classification of sinkholes in different types. Geogenic depressions develope in karst landscapes as well as in plain areas of detrital sediments on soluble rocks. The depressions are in karst landscapes localized directly in the soluble rocks like limestone or sulphate rocks (anhydrite, gypsum). It results there for solution dolines and collapse dolines in these rocks themselves.. In other cases the soluble rocks often are in large depth under overlaying claystones, siltstones, sandstones or clays, silts, sands. A cave deeply is formed under the earth's surface and when a roof failure happens, the overburden sinks after. A depression of caldera shape with abrupt slopes suddenly forms in the non-karst rock at the surface. Such erdfall-collapses in Triassic claystones develop flatter walls in the course of the time. In German such depressions are called "Erdfall" to distinguish them of dolines. Because in English the term "earth fall" has an other meaning, I will further call such depressions "erdfall-collaps". The solution of limestones and sulphate rocks results with the formation of caves and following emergence of collapse dolines and erdfall-collapses. The underground dissolution (subrosion) of rock salt is as opposed to without formation of caves. It leads to a slow lowering of the earth's surface in flat

  15. Heavy-metal contamination of soils in Saxony/Germany by foundry fumes and low-cost rapid analyses of contaminated soils by XRF

    Science.gov (United States)

    Mucke, D.

    2012-04-01

    Heavy-metal contamination of soils in Saxony/Germany by foundry fumes and low-cost rapid analysis of contaminated soils by XRF Dieter Mucke, Rolf Kumann, Sebastian Baldauf GEOMONTAN Gesellschaft für Geologie und Bergbau mbH&Co.KG, Muldentalstrasse 56, 09603 Rothenfurth, Saxony/Germany For hundreds of years in the Ore Mountains between Bohemia and Saxony silver and other ores are produced and smelted. Sulphide- and sulpharsenide-ores needed to be roasted first. In doing so the sulphide sulphur was oxidised under formation of sulphur dioxide SO2 and arsenide conversed into elemental arsenic and arsenide trioxide As2O3 respectively. Also the metals lead, cadmium and zinc are components of hut smokes, in the field of nickel foundries also nickel. The contents of soils basically reflect the geogenic conditions, which are caused by decomposition- and relocation-effects of the mineralisations, in the area of foundries also with influences by with the hut smokes anthropogenic mobilised elements. The Saxonian Agency for Environment and Geology drafted in 1992 a Soil Investigation Program with the aim of investigation of the contamination of Saxonian soils with arsenic and toxic heavy metals. In order of this Agency GEOMONTAN investigated 1164 measuring points in the grid 4 * 4 km.soil profiles and extracted soil samples for analysis. In the result of the laboratory examinations the Agency edited the "Soil atlas of the Free State of Saxony". 27 elements, pH and PAK are shown in detailed maps and allow in whole Saxony the first assessment of the contamination of soils with arsenic and toxic heavy metals. Each of the investigated soil profiles represent an area of 16 km2. Already by the different use of the districts (agricultural, industrial, urban) restricts representative values. GEOMONTAN in the meantime used at the exploration of a copper deposit in Brandenburg/Germany with approx. 50,000 single tests at drill cores a very fast low-cost method: the X Ray fluorescence

  16. Fi Investigations On Hp-Rocks From The Lower Engadine Window New Insights On Its Late Tectono-Metamorphic Evolution

    Science.gov (United States)

    Bertle, R. J.; Götzinger, M. A.; Koller, F.

    2003-04-01

    acknowledged. References: BERTLE, R. J. 2000: Zur Geologie und Geochronologie um Alp Trida (Samnaun/Schweiz) einschließlich ingenieurgeologischer Fragen der Gebirgsauflösung und des Permafrosts. - Unpubl. Msc-Thesis. Univ. Wien, 395 S. BOUSQUET, R., GOFFÉ, B., VIDAL, O., OBERHÄNSLI, R. & PATRIAT, M. 2002: The tectono-metamorphic history of the Valaisan domain from the Western to the Central Alps: new constraints on the evolution of the Alps. - Geol. Soc. America Bull., 114/2, S. 207-225. KÜSTER, M. &STÖCKHERT, B. 1997: Density changes of fluid inclusions in high-pressure low-temperature metamorphic rocks from Crete: A thermobarometric approach based on the creep strength of the host minerals. Lithos, 41, S. 151-167. MATTMÜLLER, C. R. 1996: Geometrische Untersuchung des Inntalgewölbes. - Jahrb. Geol. B.-A., 139/1, S. 45-69, Wien 1996. RING, U. 1989: Tectonogenesis of the Penninic/Austroalpine Boundary Zone: The Arosa Zone (Grisons Rätikon area, Swiss-Austrian Alps). - Unpubl. Phd.-Thesis., 177 p., Tübingen. STOECKHERT, B., RÖSSNER, G., KÜSTER, M., HEIDER, M., GUNDLACH, K. &RICHTER, D.K. 1990: High-Pressure Metamorphism of the Mesozoic Sediments in the Lower Engadine Window, Eastern Alps. - Terra Abstracts, 2, S. 34, 1990. THÖNI, M. 1981: Degree and Evolution of the Alpine Metamorphism in the Austroalpine Unit W of the Hohe Tauern in the light of K/Ar and Rb/Sr Age Determinations on Micas. - Jahrb. Geol. B.-A., 124/1, S. 111-174, Wien 1981.

  17. Stable isotopic composition of cryptocrystalline magnesite from deposits in Turkey and Austria

    Science.gov (United States)

    Horkel, K.; Ebner, F.; Spötl, Ch

    2009-04-01

    : A Stable Isotope Study. - Economic Geologie, 95, p. 429-446.

  18. Reworked planktonic Foraminifera from the Late Rupelian of the southern Upper Rhine Graben and their palaeogeographic and biostratigraphic implications

    Science.gov (United States)

    Pirkenseer, C.; Spezzaferri, S.; Berger, J.-P.

    2009-04-01

    margin of the Upper Rhine Graben. Reworked Mesozoic and Paleogene calcareous nannoplankton from the Upper Rhine Graben and the Mainz Basin confirms the data derived from planktonic Foraminifera. The existence of reworked planktonic Foraminifera influences the biostratigraphic interpretation of the assemblage ranges attributed to "Série grise" samples. Facultatively reworked planktonic Foraminifera as Subbotina utilisindex and Pseudohastigerina micra ranging from the Lutetian to the Late Rupelian should not be included in the biostratigraphic analyses, as the occurrences of these facultatively reworked species are always linked to those of exclusively Cretaceous and Eocene age. Therefore the age of the "Série grise" deposits at Allschwil-2 is most likely to be placed within the "Chiloguembelina cubensis - Globigerinella obesa / Globorotaloides variabilis"-assemblage range of Mid P20 to Final P21a, lasting considerably longer than the very short Mid P20 range based on the presence of Pseudohastigerina micra as "last occurrence"-marker (PIRKENSEER 2007). This study was funded by the Swiss National Science Foundation projects 109457 and 118025. References: BERGER, J.-P., REICHENBACHER, B., BECKER, D., et al. (2005): Eocene-Pliocene time scale and stratigraphy of the Upper Rhine Graben (URG) and the Swiss Molasse Basin (SMB). - International Journal of Earth Sciences, 94, 4: 711-731. FISCHER, H. (1965): Geologie des Gebietes zwischen Blauen und Pfirter Jura. - Beiträge zur geologischen Karte der Schweiz, NF 122: 106p. PIRKENSEER, C. (2007): Foraminifera, Ostracoda and other microfossils of the Southern Upper Rhine Graben - Palaeoecology, biostratigraphy, palaeogeography and geodynamic implications. - PhD thesis: 340p, Fribourg. ROUSSÉ, S. (2006): Architecture et dynamique des séries marines et continentales de ĺOligocène Moyen et Supérieur du Sud du Fossé Rhénan: Evolution des milieux de dépôt en contexte de rift en marge de ĺavant-pays alpin. - PhD: 471p

  19. Geothermal prospection in the Greater Geneva Basin (Switzerland and France): Architecture of the new Information System

    Science.gov (United States)

    Favre, Stéphanie; Brentini, Maud; Giuliani, Gregory; Lehmann, Anthony

    2017-04-01

    objectives and needs are similar. Concerning the architecture, the data model was developed according to the following themes: geology, hydrogeology, geophysics and geothermal energy. Each theme contains features that are characterized by a geometric shape (point, line or polygon), attribute tables and relations. The data model was designed to allow crossed requests between features though unique identifier (ID) attributes. PostgreSQL, an open-source database management system, was chosen to ensure a wide range of compatible GIS tools. This solution helps keeping the link between 2D and 3D geological data, especially through the cantonal platform (ge.ch/sitg/geologie3d) that stores and displays 3D models. To ensure the development of a geological IS, these aspects have been considered: 1) having a robust and scalable architecture 2) selecting adapted IT tools and 3) defining coherent data workflows. The future system should be able to answer queries to produce of maps, models and define protection zones, which assist an optimal management of the subsurface resources for the State of Geneva. REFERENCES Blunier, P., Tacher, L. and Parriaux, A. 2007: Systemic Approach of Urban Underground Resources Exploitation. 11th ACUUS Conference: Underground Space: Expanding the Frontiers. Athens , Greece. Brentini, M. and Favre, S. 2014: Développement d'une base de données du sous-sol dans le cadre de GEothermie 2020: intégration des forages et lignes sismiques à Genève. Internship thesis, University of Geneva, 90p. Clerc, N., Rusillon, E., Cardello, L., Moscariello, A. and Renard, P., 2016. Structural Modeling of the Geneva Basin for Geothermal Ressource Assessment. Abstract, 14th Swiss Geoscience Meeting, Geneva, Switzerland. Gabriel, P., Gietzel, J., Le, H., H., and Schaeben, H. 2015: GST: A Network Based Datastore for Geoscience Data and Geomodels and Its Implementation - ProMine's Contribution Towards Interoperability. Springer International Publishing Switzerland, 59

  20. PREFACE: Preface

    Science.gov (United States)

    Audoin, Bertrand; Dehoux, Thomas; Guillet, Yannick

    2011-02-01

    and the gala dinner took place in a wine chateau in the medieval village. We hope this experience will remain in the attendees' memories as a pleasant and convivial time. We would like to express our thanks to the members of the organizing committee, the scientific committee, and all our generous sponsors, either institutions or companies, for their help in making this event possible. We would also like to thank the scientists involved for their confidence in our organization, and for their contributions. As unanimously decided by the attendees, the next symposium will be held in Japan, most likely in 2012. The papers published in this volume of the Journal of Physics: Conference Series provide a collection of state-of-the-art and recent advances in research and applications of laser ultrasonics as presented at this second Symposium. Bertrand Audoin - Conference ChairThomas Dehoux - Conference proceedings co-editorYannick Guillet - Conference proceedings co-editor Conference photograph Scientific committee Bertrand AudoinUniversité Bordeaux 1, France Alain BlouinNRC, Canada Christ GlorieuxKatholieke Universiteit Leuven, Belgium Vitalyi GusevUniversité du Maine, France Peter HessUniversity of Heidelberg, Germany Alexander A KarabutovMoscow State University, Russia Sridhar KrishnaswamyNorthwestern University, USA Humphrey MarisBrown University, USA Jean-Pierre MonchalinNRC, Canada Todd MurrayBoston University, USA Makoto OchiaiToshiba Corp, Japan Menglu QianTongji University, China Daniel RoyerEcole Supérieure de Physique et de Chimie, France Hervé TrétoutDassault Aviation, France Hubert VoillaumeEADS, France Oliver B WrightHokkaido University, Japan Shu-yi ZhangNanjing University, China Organizing committee Bertrand AudoinChair Sandrine GuitLocal administrator Christophe Aristégui Thomas Dehoux Evelyne Dewayse Yannick Guillet Armelle Guilloux

  1. Modeling of NOx and Soot Formation in Diesel Combustion Modélisation de la formation des NOx et de la suie en combustion diesel

    Directory of Open Access Journals (Sweden)

    Dederichs A. S.

    2006-12-01

    bibliothèque, leurs termes sources sont calculés et une équation de transport pour les masses moyennes est résolue dans le code de mécanique des fluides. Les termes sources sont obtenus à partir de calcul en chimie détaillée sur une configuration de type flamme à contre-courant. Les équations de transports de la variable de mélange et de sa variance sont résolues, et le terme source chimique est obtenu par une technique de PdF présumé avec des fonctions bêta et une distribution log-normale pour la dissipation scalaire. Le modèle a été testé sur des flammes de jet laminaires et turbulentes. En appliquant une stratégie de réduction des termes sources, il a été rendu applicable au calcul de la simulation des suies Diesel pour plusieurs températures et pressions de l'oxydant. De plus, différentes formulations d'équations de flamelets ont été testées et leur précision évaluée par rapport à une expérience de flamme turbulente.

  2. Potential of multispectral synergism for observing tropospheric ozone by combining IR and UV measurements from incoming LEO (EPS-SG) and GEO (MTG) satellite sensors

    Science.gov (United States)

    Costantino, Lorenzo; Cuesta, Juan; Emili, Emanuele; Coman, Adriana; Foret, Gilles; Dufour, Gaëlle; Eremenko, Maxim; Chailleux, Yohann; Beekmann, Matthias; Flaud, Jean-Marie

    2017-04-01

    Satellite observations offer a great potential for monitoring air quality on daily and global basis. However, measurements from currently in orbit sensors do not allow to probe surface concentrations of gaseous pollutants such as tropospheric ozone (Liu et al., 2010). Using single-band approaches based on spaceborne measurements of either thermal infrared radiance (TIR, Eremenko et al., 2008) or ultraviolet reflectance (UV, Liu et al., 2010) only ozone down to the lower troposphere (3 km) may be observed. A recent multispectral method (referred to as IASI+GOME-2) combining the information of IASI and GOME-2 (both onboard MetOp satellites) spectra, respectively from the TIR and UV, has shown enhanced sensitivity for probing ozone at the lowermost troposphere (LMT, below 3 km of altitude) with maximum sensitivity down to 2.20 km a.s.l. over land, while sensitivity for IASI or GOME-2 only peaks at 3 to 4 km at lowest (Cuesta et al., 2013). Future spatial missions will be launched in the upcoming years on both low and geostationary orbits, such as EPS-SG (EUMETSAT Polar System Second Generation) and MTG (Meteosat Third Generation), carrying respectively IASI-NG (for IR) and UVNS (for UV), and IRS (for IR) and UVN (Sentinel 4, for UV). This new-generation sensors will enhance the capacity to observe ozone pollution and particularly by synergism of multispectral measurements. In this work we develop a pseudo-observation simulator and evaluate the potential of future EPS-SG and MTG satellite observations, through IASI-NG+UVNS and IRS+UVN multispectral methods to observe near-surface O3. The pseudo-real state of atmosphere (nature run) is provided by MOCAGE (MOdèle de Chimie Atmosphérique à Grande Échelle) chemical transport model. Simulations are calibrated by careful comparisons with real data, to ensure the best coherence between pseudo-reality and reality, as well as between the pseudo-observation simulator and existing satellite products. We perform full and

  3. Potential of multispectral synergism for observing ozone pollution by combining IASI-NG and UVNS measurements from the EPS-SG satellite

    Science.gov (United States)

    Costantino, Lorenzo; Cuesta, Juan; Emili, Emanuele; Coman, Adriana; Foret, Gilles; Dufour, Gaëlle; Eremenko, Maxim; Chailleux, Yohann; Beekmann, Matthias; Flaud, Jean-Marie

    2017-04-01

    Present and future satellite observations offer great potential for monitoring air quality on a daily and global basis. However, measurements from currently orbiting satellites do not allow a single sensor to accurately probe surface concentrations of gaseous pollutants such as tropospheric ozone. Combining information from IASI (Infrared Atmospheric Sounding Interferometer) and GOME-2 (Global Ozone Monitoring Experiment-2) respectively in the TIR and UV spectra, a recent multispectral method (referred to as IASI+GOME-2) has shown enhanced sensitivity for probing ozone in the lowermost troposphere (LMT, below 3 km altitude) with maximum sensitivity down to 2.20 km a.s.l. over land, while sensitivity for IASI or GOME-2 alone only peaks at 3 to 4 km at the lowest.In this work we develop a pseudo-observation simulator and evaluate the potential of future EPS-SG (EUMETSAT Polar System - Second Generation) satellite observations, from new-generation sensors IASI-NG (Infrared Atmospheric Sounding Interferometer - New Generation) and UVNS (Ultraviolet Visible Near-infrared Shortwave-infrared), to observe near-surface O3 through the IASI-NG+UVNS multispectral method. The pseudo-real state of the atmosphere is provided by the MOCAGE (MOdèle de Chimie Atmosphérique à Grande Échelle) chemical transport model. We perform full and accurate forward and inverse radiative transfer calculations for a period of 4 days (8-11 July 2010) over Europe.In the LMT, there is a remarkable agreement in the geographical distribution of O3 partial columns between IASI-NG+UVNS pseudo-observations and the corresponding MOCAGE pseudo-reality. With respect to synthetic IASI+GOME-2 products, IASI-NG+UVNS shows a higher correlation between pseudo-observations and pseudo-reality, which is enhanced by about 12 %. The bias on high ozone retrieval is reduced and the average accuracy increases by 22 %. The sensitivity to LMT ozone is also enhanced. On average, the degree of freedom for signal is

  4. Savoirs mondains, savoirs savants : les femmes et leurs cabinets de curiosités au siècle des Lumières

    Directory of Open Access Journals (Sweden)

    Adeline Gargam

    2010-01-01

    Full Text Available Dans la France des Lumières, la culture de la curiosité est un phénomène de mode mais surtout un jeu social et intellectuel. La présente étude entend retracer l’histoire d’une trentaine de cabinets féminins de curiosité tenus à cette époque. Des femmes fortunées de l’aristocratie et de la bourgeoisie parisienne et provinciale ont alors constitué sous l’emprise de leur libido sciendi des cabinets d’alchimie, de minéralogie, de physique‑chimie, d’histoire naturelle et d’anatomie naturelle et artificielle. Ces cabinets obéissent à une typologie particulière. Il en existe deux catégories : les cabinets d’amateurs, constitués pour la parade et le spectacle des visiteurs et fonctionnant comme de véritables écoles de plaisirs intellectuels et éducatifs ; les cabinets à finalité scientifique et didactique, formés par des savantes expérimentées qui se livrent dans leurs laboratoires à des recherches personnelles et expérimentales au nom des progrès de la science médicale et de l’instruction publique. La réflexion porte aussi sur le fonctionnement de ces cabinets privés de curiosité, particulièrement sur leur mode de constitution, leur décor intérieur ainsi que sur le contenu des collections qui nécessitaient certaines techniques d’organisation, d’acquisition et de conservation communes à celles de leurs homologues masculins.During the Enlightenment in France, curiosity culture constituted both a fashion and an intellectual and social game.  This article explores thirty cabinets of  curiosities run by women during this period. Wealthy women from the Parisiain and provincial aristocracy and middle classes organized cabinets in alchemy, mineralogy, physics and chemistry, natural history and biology studies. These cabinets can be divided into two distinct categories. The first represented amateur interests; they were developed for show and served as schools for intellectual and

  5. [Lecturers in chemistry at the Medical Faculty of the University of Nagyszombat].

    Science.gov (United States)

    Szabadváry, F; Vámos, E

    1994-01-01

    After a short introduction on the development of the medieval universities at Pécs, Obuda, and Pozsony, and mentioning those who lectured in medicine in Hungary, the authors emphasise that modern chemistry was born during the 16th and 17th century. They stress the role of Paracelsus who invented iatro-chemistry, and that the first independent chairs, were founded in Germany in the beginning of 17th century at Altdorf, Marburg, Jéna, but were followed suit by Paris, when the Jardin des Plantes were erected. The first chemical textbook, the Cours de Chimie (Paris 1665), was also the work of a Frenchman, namely Nicolas Lémery (1645-1715). From the 18th century chemistry was also included in the curriculum of medical education in Hungary. Among the chairs of the newly founded medical faculty at Nagyszombat we find the chemical-botanical department in 1769. Its first professor was an Austrian physician Jakab Winterl (1773-1809), who had been a head physician at Selmecbánya, in Northern Hungary. Owing to a rash and premature publication Winterl's international reputation was unfortunately undermined in the last century by a leading German science historian, Hermann Kopp. The authors stress, however, that Winterl indeed played an important role in organizing the chemical department, and purchasing all the necessary equipment needed for up to date researches and analyses. And above all, in his Prolusiones ad chemiam saeculi decimi noni, he foresaw many forthcoming paths and discoveries of 19th century chemistry. After Winterl's retirement the department was divided into two parts. Pál Kitaibel (1757-1817) led the botanica department and János schuster (1777-1838) the other one for chemistry. Kitaibel made a name for himself by depicting Hungarian flora, but he also made discoveries in chemistry. He discovered chlore lime, before Tennant in 1795, a material which might have been used for whitening textiles. Schuster, on the other hand, introduced a system of Hungarian

  6. Evaluation d'une approche pedagogique respectant les facons d'apprendre des filles en sciences et en TIC en 9e annee au Nouveau-Brunswick

    Science.gov (United States)

    Lirette-Pitre, Nicole T.

    2009-07-01

    La reussite scolaire des filles les amene de plus en plus a poursuivre une formation postsecondaire et a exercer des professions qui demandent un haut niveau de connaissances et d'expertise scientifique. Toutefois, les filles demeurent toujours tres peu nombreuses a envisager une carriere en sciences (chimie et physique), en ingenierie ou en TIC (technologie d'information et de la communication), soit une carriere reliee a la nouvelle economie. Pour plusieurs filles, les sciences et les TIC ne sont pas des matieres scolaires qu'elles trouvent interessantes meme si elles y reussissent tres bien. Ces filles admettent que leurs experiences d'apprentissage en sciences et en TIC ne leur ont pas permis de developper un interet ni de se sentir confiante en leurs habiletes a reussir dans ces matieres. Par consequent, peu de filles choisissent de poursuivre leurs etudes postsecondaires dans ces disciplines. La theorie sociocognitive du choix carriere a ete choisie comme modele theorique pour mieux comprendre quelles variables entrent en jeu lorsque les filles choisissent leur carriere. Notre etude a pour objet la conception et l'evaluation de l'efficacite d'un materiel pedagogique concu specifiquement pour ameliorer les experiences d'apprentissage en sciences et en TIC des filles de 9e annee au Nouveau-Brunswick. L'approche pedagogique privilegiee dans notre materiel a mis en oeuvre des strategies pedagogiques issues des meilleures pratiques que nous avons identifiees et qui visaient particulierement l'augmentation du sentiment d'auto-efficacite et de l'interet des filles pour ces disciplines. Ce materiel disponible par Internet a l'adresse http://www.umoncton.ca/lirettn/scientic est directement en lien avec le programme d'etudes en sciences de la nature de 9e annee du Nouveau-Brunswick. L'evaluation de l'efficacite de notre materiel pedagogique a ete faite selon deux grandes etapes methodologiques: 1) l'evaluation de l'utilisabilite et de la convivialite du materiel et 2

  7. A Paradigm shift to an Old Scheme for Outgoing Longwave Radiation

    Science.gov (United States)

    McDonald, Alastair B.

    2016-04-01

    nérales Sur Les Températures Du Globe Terrestre Et Des Espaces Planétaires.' Annales de Chimie et de Physique 27: 136-67, translated by Raymond T. Pierrehumbert http://www.nature.com/nature/journal/v432/n7018/extref/432677a-s1.pdf Philipona, Rolf, Bruno Dürr, Atsumu Ohmura, and Christian Ruckstuhl. 2005. 'Anthropogenic Greenhouse Forcing and Strong Water Vapor Feedback Increase Temperature in Europe'. Geophysical Research Letters 32 (19): L19809. doi:10.1029/2005GL023624. Saussure, Horace-Benedict de. 1786. 'Chapter XXXV. Des Causes du Froid qui Regne sur les Montagnes'. In Voyages dans les Alpes, II:347-71. Neuchatel: Fauche-Borel. http://gallica.bnf.fr/ark:/12148/bpt6k1029499.r=.langFR, translated by Alastair B. McDonald, http://www.abmcdonald.freeserve.co.uk/saussure/CHAPTER%2035.pdf. Thorne, Peter W., Philip Brohan, Holly A. Titchner, et al. 2011. 'A Quantification of Uncertainties in Historical Tropical Tropospheric Temperature Trends from Radiosondes'. Journal of Geophysical Research: Atmospheres 116 (D12): n/a - n/a. doi:10.1029/2010JD015487. Wild, Martin, Doris Folini, Christoph Schär, et al. 2013. 'The Global Energy Balance from a Surface Perspective'. Climate Dynamics 40 (11-12): 3107-34. doi:10.1007/s00382-012-1569-8. White, James W.C., Alley, Richard B., Archer, David E., et al. 2013. Abrupt Impacts of Climate Change: Anticipating Surprises. Washington, D.C.: National Academies Press. http://www.nap.edu/catalog/18373.

  8. Impact de l’alteration sur le bilan chimique des diatexites du Massif de l’Edough (Annaba, NE Algérien

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    Hadj-Zobir, Soraya

    2012-12-01

    Full Text Available The studied section, located on the eastern part of the Edough massif (region of Annaba, Algeria, is characterized by a Mediterranean climate and the area is one of the most humid of Algeria (precipitation between 750 and 1200 mm/year. It consists of diatexites with homogeneous petrographic and metamorphic facies. The primary minerals are quartz, feldspar, oligoclase and biotite whereas weathering products are mostly represented by illite and montmorillonite. Although all samples comprise the same mineral composition, due to changes in the mode, the chemistry of this diatexites is very heterogeneous. The chemical analyses of the rocks reveal a progressive evolution in the composition in terms of gains and losses in Ca, Na, K, Fe, Mg and in trace elements. The values of the Chemical Index of Change (CIA = 62.79 - 68.32, of the Chemical index of Weathering (CIW = 63.92 - 70.79, the Freshness Index (IFRAIS = 76 - 46.35 and the high value of the loss of ignition (L.O.I > 2% as well as the Rb/Sr ratio >1 indicate that the distribution of the chemical elements along the section is entirely controlled by weathering (bisiallitisation alteration type during a long time.

    [fr] La zone d’étude, constituée de diatexites, est située sur le flanc NE du massif de l’Edough (région de Annaba/ Algérie. Le massif, qui est l’un des plus arrosé d’Algérie (entre 750 et 1200 mm/an, se caractérise par un climat de type méditerranéen. Les diatexites montrent un faciès pétrographique et métamorphique homogène. Les minéraux primaires dominants sont le quartz, le feldspath potassique, l’oligoclase et la biotite alors que ceux d’altération sont représentés par des minéraux néoformés tels que la kaolinite, l’illite, la montmorillonite et dans une moindre mesure la séricite. A l’opposé de la minéralogie, la chimie des diatexites est hétérogène. Les analyses chimiques du matériel prélevé, du sommet vers la base des roches

  9. MOCAGE-accident: From research to operational applications

    Science.gov (United States)

    Martet, M.; Josse, M.; Peuch, Mr.; Peuch, M.; Bonnardot, Mr.

    2009-09-01

    MOCAGE (Modèle de Chimie Atmosphérique à Grande Echelle) is the multi-scale 3D Chemistry and Transport Model of Météo-France. From air quality forecasting to the study of interactions between climate and chemistry, MOCAGE is a flexible tool that is currently used for both research on atmospheric composition (over 35 publications in the international literature) and operations in Météo-France and at several collaborating institutes. In particular, MOCAGE products are used for the French operational Air Quality platform Prév'Air as well as in projects building up the GMES Atmospheric Service. Here, we present a new specific configuration "MOCAGE-accident”, currently used in pre-operations trial by Météo-France forecasters, in support of our international responsibilities as RSMC (Regional Meteorological Specialized Centre) and VAAC (Volcanic Ash Advisory Centre). Briefly, a semi-lagrangian scheme is used for advection (Williamson and Rash, 1989), while turbulent diffusion, using the Louis scheme (Louis, 1979) and convection, using the Bechtold scheme (Kain and Fritsch, 1990 and Bechtold, 2001) are parameterized. In the specific "accident” configuration, no chemical reactions are considered and a module allows to specify the temporal and geometrical characteristics of the release. Three types of pollutants can be considered : - tracers: no interactions between this tracer and the other atmospheric components are considered ; only transport, wet and dry deposition are taken into account. - radionucleides: in this case, radioactive disintegration is treated following the type of radionuclide and its lifetime. - volcanic ashes: solid materials are considered and sedimentation of the particles is also considered. Concerning the current pre-operations trial, the horizontal resolution of MOCAGE-accident is 0,5° all over the globe, with 47 levels from surface to 5 hPa. This model is thus able to represent accidental emissions on every place of the world, in

  10. Hybrid Materials Based on Magnetic Layered Double Hydroxides: A Molecular Perspective.

    Science.gov (United States)

    Abellán, Gonzalo; Martí-Gastaldo, Carlos; Ribera, Antonio; Coronado, Eugenio

    2015-06-16

    Design of functional hybrids lies at the very core of synthetic chemistry as it has enabled the development of an unlimited number of solids displaying unprecedented or even improved properties built upon the association at the molecular level of quite disparate components by chemical design. Multifunctional hybrids are a particularly appealing case among hybrid organic/inorganic materials. Here, chemical knowledge is used to deploy molecular components bearing different functionalities within a single solid so that these properties can coexist or event interact leading to unprecedented phenomena. From a molecular perspective, this can be done either by controlled assembly of organic/inorganic molecular tectons into an extended architecture of hybrid nature or by intercalation of organic moieties within the empty channels or interlamellar space offered by inorganic solids with three-dimensional (MOFs, zeolites, and mesoporous hosts) or layered structures (phosphates, silicates, metal dichalcogenides, or anionic clays). This Account specifically illustrates the use of layered double hydroxides (LDHs) in the preparation of magnetic hybrids, in line with the development of soft inorganic chemistry processes (also called "Chimie Douce"), which has significantly contributed to boost the preparation hybrid materials based on solid-state hosts and subsequent development of applications. Several features sustain the importance of LDHs in this context. Their magnetism can be manipulated at a molecular level by adequate choice of constituting metals and interlayer separation for tuning the nature and extent of magnetic interactions across and between planes. They display unparalleled versatility in accommodating a broad range of anionic species in their interlamellar space that encompasses not only simple anions but chemical systems of increasing dimensionality and functionalities. Their swelling characteristics allow for their exfoliation in organic solvents with high

  11. "Hexagonal molybdenum trioxide"--known for 100 years and still a fount of new discoveries.

    Science.gov (United States)

    Lunk, Hans-Joachim; Hartl, Hans; Hartl, Monika A; Fait, Martin J G; Shenderovich, Ilya G; Feist, Michael; Frisk, Timothy A; Daemen, Luke L; Mauder, Daniel; Eckelt, Reinhard; Gurinov, Andrey A

    2010-10-18

    ]+ cations and H2O. The “chimie douce” reaction of MoO3·0.155NH3·0.440H2O with a 1:1 mixture of NO/NO2 at 100 °C resulted in the synthesis of MoO3·0.539H2O. This material is of great interest as a host of various molecules and cations.

  12. Effets néfastes sur la stabilité des solutions polyacrylamides utilisées dans la récupération assistée du pétrole Harmful Effects of Formaldehyde on the Stability of Polyacrylamide Solutions Used in Enhanced Oil Recovery

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    Catherin G.

    2006-11-01

    Full Text Available L'étude de la dégradation oxydante des polyacrylamides (PAA et HPAA en solution aqueuse nous a permis de trouver que du formaldéhyde est produit par l'oxydation de l'acrylamide résiduel. Du formaldéhyde est aussi produit par l'oxydation du méthanol résiduel quand ce non-solvant a été utilisé pour purifier les PAA et HPAA par précipitation de leurs solutions aqueuses. Ce formaldéhyde est responsable de la formation de dérivés insolubles nuisibles pour les propriétés rhéologiques utiles des solutions. Ce résultat rejoint ceux d'études antérieures où un effet comparable a été observé après addition de formaldéhyde aux solutions de PAA et HPAA. Mais l'examen de la littérature relative à la chimie du formaldéhyde montre que les réactions d'oxydation et d'addition qui ont été suggérées pour rendre compte de cet effet sont inadéquates dans le milieu considéré. Le schéma que nous proposons explique mieux les phénomènes observés. Nous avons aussi montré que l'oxydo-réduction du formaldéhyde est responsable de la formation de radicaux libres sur les polyacrylamides. II était alors possible de conclure, sans avoir recours à d'autres expériences, que le formaldéhyde ne doit pas être utilisé dans la récupération assistée du pétrole pour protéger les solutions des polyacrylamides contre la biodégradation. In a study of the oxidation of aqueous solutions of the polyacrylamides PAA and HPAA, we have found that formaldehyde is an oxidation product both of acrylamide residual in the commercial polymers and of the methanol residual in polymers purified by methanol precipitation from aqueous solutions. The presence of formaldehyde in turn causes the production of insoluble derivatives which spoil the rheological properties of polymer solutions. This result reinforces those of previous studies where a similar effect was observed after formaldehyde was added to solutions of PAA and HPAA. Examination of the

  13. Modelling of primary aerosols in the chemical transport model MOCAGE: development and evaluation of aerosol physical parameterizations

    Science.gov (United States)

    Sič, B.; El Amraoui, L.; Marécal, V.; Josse, B.; Arteta, J.; Guth, J.; Joly, M.; Hamer, P. D.

    2015-02-01

    This paper deals with recent improvements to the global chemical transport model of Météo-France MOCAGE (Modèle de Chimie Atmosphérique à Grande Echelle) that consists of updates to different aerosol parameterizations. MOCAGE only contains primary aerosol species: desert dust, sea salt, black carbon, organic carbon, and also volcanic ash in the case of large volcanic eruptions. We introduced important changes to the aerosol parameterization concerning emissions, wet deposition and sedimentation. For the emissions, size distribution and wind calculations are modified for desert dust aerosols, and a surface sea temperature dependant source function is introduced for sea salt aerosols. Wet deposition is modified toward a more physically realistic representation by introducing re-evaporation of falling rain and snowfall scavenging and by changing the in-cloud scavenging scheme along with calculations of precipitation cloud cover and rain properties. The sedimentation scheme update includes changes regarding the stability and viscosity calculations. Independent data from satellites (MODIS, SEVIRI), the ground (AERONET, EMEP), and a model inter-comparison project (AeroCom) are compared with MOCAGE simulations and show that the introduced changes brought a significant improvement on aerosol representation, properties and global distribution. Emitted quantities of desert dust and sea salt, as well their lifetimes, moved closer towards values of AeroCom estimates and the multi-model average. When comparing the model simulations with MODIS aerosol optical depth (AOD) observations over the oceans, the updated model configuration shows a decrease in the modified normalized mean bias (MNMB; from 0.42 to 0.10) and a better correlation (from 0.06 to 0.32) in terms of the geographical distribution and the temporal variability. The updates corrected a strong positive MNMB in the sea salt representation at high latitudes (from 0.65 to 0.16), and a negative MNMB in the desert

  14. Modelling of primary aerosols in the chemical transport model MOCAGE: development and evaluation of aerosol physical parameterizations

    Directory of Open Access Journals (Sweden)

    B. Sič

    2015-02-01

    Full Text Available This paper deals with recent improvements to the global chemical transport model of Météo-France MOCAGE (Modèle de Chimie Atmosphérique à Grande Echelle that consists of updates to different aerosol parameterizations. MOCAGE only contains primary aerosol species: desert dust, sea salt, black carbon, organic carbon, and also volcanic ash in the case of large volcanic eruptions. We introduced important changes to the aerosol parameterization concerning emissions, wet deposition and sedimentation. For the emissions, size distribution and wind calculations are modified for desert dust aerosols, and a surface sea temperature dependant source function is introduced for sea salt aerosols. Wet deposition is modified toward a more physically realistic representation by introducing re-evaporation of falling rain and snowfall scavenging and by changing the in-cloud scavenging scheme along with calculations of precipitation cloud cover and rain properties. The sedimentation scheme update includes changes regarding the stability and viscosity calculations. Independent data from satellites (MODIS, SEVIRI, the ground (AERONET, EMEP, and a model inter-comparison project (AeroCom are compared with MOCAGE simulations and show that the introduced changes brought a significant improvement on aerosol representation, properties and global distribution. Emitted quantities of desert dust and sea salt, as well their lifetimes, moved closer towards values of AeroCom estimates and the multi-model average. When comparing the model simulations with MODIS aerosol optical depth (AOD observations over the oceans, the updated model configuration shows a decrease in the modified normalized mean bias (MNMB; from 0.42 to 0.10 and a better correlation (from 0.06 to 0.32 in terms of the geographical distribution and the temporal variability. The updates corrected a strong positive MNMB in the sea salt representation at high latitudes (from 0.65 to 0.16, and a negative MNMB in

  15. The development of the Middle Triassic tectonical controlled Germanic Basin of Central Europe and the palaeoenvironmental related distribution of marine and terrestrial reptiles

    Science.gov (United States)

    Diedrich, Cajus G.

    2010-05-01

    comparison to convergent developed sirenia. Palaeogeography, Palaeoclimatology, Palaeoecology, (in review). Diedrich, 2010b. The vertebrate fauna of the Lower Ladinian (Middle Triassic) from Lamerden (Germany) and contribution to the palaeoecology, anatomy and palaeogeography of the Germanic Basin reptiles. Palaeogeography, Palaeoclimatology, Palaeoecology, (in review). Diedrich, 2010c. The palaeogeographic reconstructions of the Middle Triassic tectonical controlled carbonatic Germanic Basin of Central Europe - a northern Tethys connected cratonic marine Basin - coastal basin margin mappings by the use of reptile footprint rich intertidal and sabkha environments. Abstract, Fifth International Conference on the Geology of the Tethys Realm, Quena-Luxor,Egypt), 3-5. Diedrich, in prep. The shallow marine fish and sauropterygian reptile vertebrate fauna of the Germanic Basin from the atavus/pulcher Bonebeds in the Bad Sulza Fm (Illyrian, Middle Triassic) of Bad Sulza (Central Germany). Diedrich, C. and Trostheide, F. 2007. Auf den Spuren der terresten Muschelkalksaurier und aquatischen Sauropterygier vom obersten Röt bis zum Mittleren Muschelkalk (Unter-/Mitteltrias) von Sachsen-Anhalt. Abhandlungen und Berichte für Naturkunde, 30, 5-56. Föhlisch, K. 2007. Überlieferungen seismischer Aktivität im Unteren Muschelkalk. Beiträge zur Geologie Thüringens, N.F. 14, 55-83. Furrer, H. 1995. The Kalkschieferzone (Upper Meride estone Ladinian) near Meride (Canton Ticino, Southern Switzerland) and the evolution of a Middle Triassic intraplatform basin. Eclogae geolicae Helvetiae, 88(3), 827-852. Hagdorn, H. 1990. Das Muschelkalk/Keuper-Bonebed von Crailsheim. In: Weidert, W. K. (Ed.), Klassische Fundstellen der Paläontologie, Band 2. 78-88. Goldschneck-Verlag, Stuttgart. Hagdorn, H., E. Nitsch, Aigner, T. and Simon, T. 2009. Field guide 6th international Triassic field workshop (Pan-European Correlation of the Triassic) Triassic of Southwest Germany. September 7-11, 2009, www

  16. Préface

    Science.gov (United States)

    Paulus, Werner; Meinnel, Jean

    2003-02-01

    En 1994, l'attribution du prix Nobel à Cliff Shull et Bert Brockhouse pour leurs travaux de pionniers pendant les années 50, concernant tant la diffusion élastique des neutrons que la diffusion inélastique, a été la reconnaissance éclatante de l'importance de la diffusion neutronique pour toute la communauté scientifique.Le grand intérêt du neutron pour la recherche s'appuie principalement sur ses propriétés physiques particulières :- les neutrons utilisés pour la caractérisation de la matière (et fournis en relativement grandes quantités par les réacteurs ou les sources à spallation) disposent de longueurs d'onde et d'énergies correspondant directement aux distances interatomiques et aux énergies d'agitation de la matière. Ainsi, par diffusion neutronique, on peut étudier en même temps la structure et le comportement dynamique de la matière ;- le fait que le neutron soit doué d'un moment magnétique lui permet d'interagir avec tout atome porteur d'un moment magnétique. Ceci permet de caractériser intimement le comportement magnétique de la matière à l'échelle microscopique ;- la possibilité de pouvoir varier facilement le contraste d'un même élément en utilisant ses différents isotopes fait du neutron un outil irremplaçable en chimie et physique du solide ainsi qu'en biologie et matière molle ;- enfin, n'ayant pas de charge électrique, les neutrons peuvent pénétrer la matière sans être absorbés significativement, ce qui rend possible une caractérisation non destructive des contraintes et textures sur de grosses pièces des matériaux.Toutes les qualités des neutrons mentionnées ci-dessus permettent de comprendre l'importance de la diffusion neutronique pour des domaines très nombreux et très différents à la fois en recherche fondamentale mais aussi pour des applications industrielles. L'utilisation de l'outil-neutron demande toutefois non seulement une bonne connaissance des différents mécanismes d

  17. Editorial

    Directory of Open Access Journals (Sweden)

    José Yvan Pereira Leite

    2010-11-01

    Santa Cruz. C’est une initiative qui veut mettre en valeur la diffusion scientifique liée à l’intériorisation des Instituts Federaux dans tout le Brésil. La publication de la revue au Campus Santa Cruz du IFRN représente le compromis de l’Institution avec le développement centré sur la diffusion scientifique de cet important réseau d’Éducation, Sciences et Technologie. Dans ce context la HOLOS gagne l’intérieur brésilien et le monde, du fait que ses éditions s’elargissent par l’indexation au Directory of Open Access Journals (www.doaj.org, une plateforme d’accès ouvert au monde. La lecture peut être regroupée pour les intéressés aux thèmes concernant l’environnement qui dissertent sur: l’utilisation des décharges sanitaires pour la réduction de l’émission des gas à effet de serre; le SIG comme matériel d’étude pour la prévention des innondations due aux pluies; la sécurité chimique des logements; et les activités liées a l’élevage de crevettes. Ces articles font converger société et academie et présentent des alternatives aux problèmes discutés. Il est possible aussi d’ouvrir des discutions sur les thèmes d’ingénierie comme: l’évaluation des propriétés thermophysiques des liquides pour réfrigération , l’analyse de performance des huiles biodégradable en comparaison avec les huiles minérales; ou encore l’analyse d’un brûleur commercial infrarouge adapté á un éjecteur et la vérification de leurs niveaux d'émission de polluants. Dans le domaine de l’enseignement les articles présentés traitent spécifiquement de l’enseignement de la phisyque et de la chimie pour l’éducation professionnelle. Dans le domaine de la chimie organique, les thèmes socio-scientifiques mettent l’accent sur la Science, la Technologie et la Societé. Dans l’enseignement de la physique, deux travaux sont presentés: l’”experimentothèque” comme alternative à l’enseignement au lycée et l

  18. Geochemical Origin of Biological Molecules

    Science.gov (United States)

    Bassez, Marie-Paule

    2013-04-01

    Conference and abstract in OLEB, 2008, 39 (3-4) 223. BASSEZ M.P. 2009 Prebiotic synthesis under hydothermal conditions, C. R. Chimie, Académie des Sciences, Paris 12 (6-7) : 801-807. BASSEZ M.P. 2012 A model for a geochemical origin of life in preparation BASSEZ M.P., TAKANO Y., OHKOUCHI N. 2009a Organic analysis of peridotite rocks from Ashadze and Logatchev hydrothermal sites, Int. J. Mol. Sci. 10(7): 2986-2998. BASSEZ M.P., TAKANO Y., OHKOUCHI N. 2009b Organic analysis of peridotite rocks from the MAR, AGU fall meeting, P43C-1441, San Francisco, 14-18/12/2009. BASSEZ M.P., TAKANO Y. 2010a Prebiotic organic globules, Nature Precedings: Posted 21 Jul http://hdl:10101/npre.2010.4694.1. BASSEZ M.P., TAKANO Y., OHKOUCHI N. 2010b Organic analysis of peridotite rocks, First chemical steps towards the Origin of Life colloquium, Turin 16-17/09/2010. BASSEZ M.P., TAKANO Y., OHKOUCHI N. 2011a A search for prebiotic molecular signatures inside rocks, Geobiology in Space exploration workshop, P sans n°, Marrakech 07-14/02/2011. BASSEZ M.P., TAKANO Y., OHKOUCHI N. 2011b Detection of molecular biosignatures inside rocks, Origins 2011 ISSOL and Bioastronomy conference, P2-17, Montpellier, 04-08/07/2011. BASSEZ M.P., TAKANO Y., 2011c Organic microstructures, Origins 2011 ISSOL and Bioastronomy conference, P2-34, Montpellier, 04-08/07/2011. BASSEZ M.P., TAKANO Y. KOBAYASHI K. 2011d Prebiotic organic microstructures, Nature Precedings: Posted 14 Nov. http://hdl.handle.net/10101/npre.2011.4694.2 BASSEZ M.P., TAKANO Y., KOBAYASHI K. 2012a Prebiotic organic microstructures, Origin of Life Gordon Research Conference P4, Galveston, 08-13/01/2012. BASSEZ M.P., TAKANO Y., KOBAYASHI K. 2012b Prebiotic organic microstructures, Orig. Life Evol. Biosph. 42 (4) : 307-316.

  19. Conception et calibration d'un sonoreacteur pour l'oxydation de la cellulose par le systeme TEMPO/NaOCl/NaBr

    Science.gov (United States)

    Paquin, Michel

    Avec le contexte economique actuel dans le domaine des pates et papiers au Canada, l'industrie se doit de diversifier ses produits mis en marche. La fermeture de plus de 20 usines depuis 2005, une baisse du PIB de l'industrie de 1,4 milliard CAD entre 1999--2008, une baisse de la demande de 2,4 %, une diminution du prix de la pate de 20,9 % depuis juillet 2009. La delocalisation du secteur vers l'Asie et l'hemisphere sud sont autant de raisons pour laquelle l'industrie se doit d'etre a l'avant plan de nouvelle technologie a base de fibre de bois. Pour augmenter leur rentabilite, l'industrie se doit de diversifier ses produits dans d'autres secteurs que le simple fabricant de papier impression-ecriture. Sa diversification passe par l'elaboration de nouveaux papiers a valeur ajoutee (papier conducteur, papier bioactif, etc.), par l'utilisation de la biomasse forestiere pour la production d'energie, par l'utilisation de la biomasse forestiere pour l'elaboration d'une plateforme de chimie verte, par l'utilisation de la lignine pour le developpement de polymeres et par l'utilisation de la fibre cellulosique pour la fabrication de nanomateriaux. La fabrication de nanofibrille de cellulose peut devenir un des produits qui servira a diversifier la production des usines de pates et papiers. Les nanofibrilles de cellulose possedent des proprietes mecaniques et chimiques exceptionnelles. Les nanofibrilles de cellulose sont fabriquees a partir d'une oxydation selective de la pate kraft de feuillu avec le systeme TEMPO-NaOCl-NaBr. L'oxydation selective de l'alcool primaire en C6 du monomere de glucose sous forme de carboxylates engendre une modification chimique de la cellulose qui accroit l'hydrophilicite des fibrilles. Suite a cette oxydation, nous devons effectuer une desintegration mecanique de la fibre kraft de feuillu oxydee pour separer les fibrilles. Le processus d'oxydation de la fibre par le systeme TEMPO-NaOCl-NaBr et sa defibrillation par la suite engendre une

  20. Kinetic Modeling using the Single-Event Methodology: Application to the Isomerization of Light Paraffins Modélisation cinétique basée sur la méthodologie des événements constitutifs : application à l’isomérisation des paraffines légères

    Directory of Open Access Journals (Sweden)

    Surla K.

    2011-08-01

    described by a limited number of independent kinetic parameters. The behavior of complex feedstocks can therefore be predicted based on studies conducted on model molecules. This method is applied at IFP Energies nouvelles to several refining processes. The purpose of this article is to describe this methodology in a detailed manner and to present its application to the isomerization of C5-C6 paraffins. L’établissement de modèles cinétiques est une étape importante du développement de procédés de raffinage. En effet, ces modèles peuvent être utilisés pour prédire les performances du procédé, pour optimiser l’opération de l’unité et pour concevoir de façon optimale le réacteur et le procédé associé (choix du réacteur, détermination des conditions de marche optimale, utilisation de recyclages, etc.. La demande actuelle de modèles se focalise particulièrement sur la mise au point de modèles détaillés et prédictifs, qui sont capables de prendre en compte des variations importantes dans la conduite du procédé. De ce fait, ils doivent être extrapolables à des conditions opératoires très différentes ou à des charges très diverses. La modélisation cinétique par événements constitutifs satisfait ces critères car elle permet d’obtenir une prédiction détaillée des effluents des réacteurs. La théorie des événements constitutifs a été initialement développée pour la chimie radicalaire [Clymans et Froment (1984 Comput. Chem. Eng. 8, 2, 137-142; Hillewaert et al. (1988 AIChE J. 34, 1, 17-24; Willems et Froment (1988a Ind. Eng. Chem. Res. 27, 11, 1959-1966; Willems et Froment (1988b Ind. Eng. Chem. Res. 27, 11, 1966-1971] et a été étendue ultérieurement à la catalyse acide [Baltanas et Froment (1985 Comput. Chem. Eng. 9, 1, 71-81; Baltanas et al. (1989 Ind. Eng. Chem. Res. 28, 899-910; Vynckier et Froment (1991 Modeling of the kinetics of complex processes upon elementary steps, in Kinetic and thermodynamic lumping of

  1. A 3d Regional Scale Photochemical Air Quality Model. Application to a 3 Day Summertime Episode over Paris Un modèle photochimique 3D de qualité de l'air à l'échelle régionale. Application à un épisode de 3 jours à Paris en été

    Directory of Open Access Journals (Sweden)

    Carissimo B.

    2006-12-01

    the local monitoring network (Airparif. Cet article présente AZUR, un modèle photochimique eulérien 3D de qualité de l'air pour la simulation de la pollution de l'air dans les zones urbaines et semi-urbaines. Ce modèle suit les évolutions des espèces polluantes gazeuses émises dans l'atmosphère par les transports routiers et les sources industrielles, il prend en compte les réactions chimiques auxquelles sont soumises ces espèces pour des conditions météorologiques en évolution (photolyse, pression, température, humidité, leur transport par le vent et leur diffusion turbulente en fonction de la stabilité de l'air. Le logiciel a une structure modulaire avec plusieurs composants dédiés à des processus spécifiques : -MERCURE est un modèle météorologique à moyenne échelle pour déterminer les champs de vents, les coefficients de diffusion turbulente et d'autres paramètres météorologiques. C'est un modèle 3D à l'échelle régionale qui prend en compte les différentes configurations de sols et les zones de densité urbaine. Il comprend un système complet de paramètres physiques associés à des situations de ciel dégagé. -MIEL est un modèle d'inventaire d'émissions décrivant les flux de polluants provenant des transports automobiles et des activités domestiques ou industrielles. Ce modèle comprend un inventaire des sources mobiles basé sur des comptages de véhicules sur routes associés à des informations globales sur les flux de transports déduites de données statistiques sur la population. Il utilise des facteurs d'émission spécifiques correspondant aux flottes de véhicules et à des conditions de conduites réalistes. -MoCA est un modèle photochimique en phase gazeuse décrivant la chimie de l'ozone, des NOx, et des composés hydrocarbonés. Ce modèle, avec 83 espèces et 191 réactions, correspond à un mécanisme réduit bien adapté à des conditions variées de qualité de l'air (allant de conditions en sites urbains

  2. Chromatographie à contre-courant simulé : développements et perspectives From Batch Elution to Simulated Countercurrent Chromatography

    Directory of Open Access Journals (Sweden)

    Hotier G.

    2006-11-01

    Full Text Available Les applications industrielles et le principe de fonctionnement du procédé de séparation en lit mobile ou en contre-courant simulé sont brièvement rappelés. La réalisation pratique de trois unités pilotes fonctionnant selon ce principe mais employant une technologie innovante est présentée. Cette mise en oeuvre particulière permet de tester par un simple changement de paramètres de contrôle toutes les configurations possibles de l'unité. Cet appareillage particulièrement souple est donc véritablement multitâche, ce qui permet en plus des applications en pétrochimie son emploi dans les domaines de la pharmacie, de la chimie fine et des bioséparations, où existe un grand nombre d'applications potentielles très différentes les unes des autres. Deux exemples de séparations réalisées à l'Institut Français du Pétrole sont succinctement présentés. La conclusion de ces essais est que la modélisation de ces procédés est indispensable pour pouvoir opérer correctement ce type d'unité. Une comparaison entre la chromatographie d'élution et cette technique de séparation ainsi que quelques propositions d'amélioration du procédé permettront au lecteur de se faire une idée sur l'extension potentielle de ce type de séparation. Distillation is and will for quite a long time remain the main separation technique in the refining, petrochemical and chemical industries. Some separations however cannot be performed by distillation when the products to be separated are subject to thermal degradation or when their boiling points are too close. Under these circumstances adsorption or chromatographic processes are interesting alternatives. In the 1960's and in the early 1970's the technology of the simulated moving bed, the UOP rotary valve and the application of these devices to separation processes were introduced by UOP. Nowadays simulated moving bedor countercurrentseparation processes may be found in the petrochemical industry

  3. L'effet de serre par le CO2 et les gaz traces Greenhouse Effect from CO2 and Trace Gases

    Directory of Open Access Journals (Sweden)

    Bertrand A.

    2006-11-01

    Full Text Available Selon une opinion assez répandue le CO2 et les gaz traces, produits par l'activité humaine depuis le début de la révolution industrielle (1850, principalement du fait de la combustion et de la déforestation, et progressivement accumulés dans l'atmosphère terrestre, pourraient par effet de serre provoquer au XXIe siècle un réchauffement de la Terre de quelques degrés. Les conséquences climatiques (fonte des glaces. . . en seraient désastreuses. Aussi avons-nous étudié les principaux paramètres impliqués par ce phénomène : nature de l'effet de serre, cycle du carbone, transfert de CO2 à l'échelle du globe, gaz traces, conséquences climatiques de l'effet de serre dû au CO2 et aux gaz traces. Nous en sommes arrivés aux conclusions suivantes : - La concentration de l'atmosphère en CO2 et en gaz traces augmente de façon exponentielle en absence de toute réglementation et cela parallèlement à une production humaine également exponentielle de ces mêmes substances. - On n'a encore décelé aucun accroissement de la température moyenne de la Terre dû à l'effet de serre, d'ailleurs depuis 1940 nous traversons une période de refroidissement. - L'activité humaine engendre aussi des effets antagonistes de refroidissement (action des poussières dans l'atmosphère. . . assez mal connus. - L'étude des climats anciens indique une succession régulière de périodes froides et chaudes, cela doit nous rassurer sur le risque d'une brusque modification irréversible du climat. - Cependant il est absolument nécessaire d'améliorer nos connaissances fondamentales sur les principaux facteurs réglant le climat terrestre (chimie de l'atmosphère, transfert océan-atmosphère. . . et éventuellement de restreindre la production de certains gaz traces (fréons en particulier. According to a fairly widespread opinion, CO2 and trace gases, which have been produced by human activity since the start of the industrial revolution (1850

  4. Biotechnologie : marchés et engagement des sociétés pétrolières Biotechnology: Markets and Commitments of Oil Companies

    Directory of Open Access Journals (Sweden)

    Torck B.

    2006-11-01

    Full Text Available L'intérêt pour les biotechnologies s'est accru à la suite du développement, après 1975, de techniques basées sur le génie génétique (rDNA, fusion. Bien que les prévisions soient difficiles dans ce domaine nouveau et en pleine expansion, le marché mondial des biotechnologies pourrait atteindre en l'an 2000, 150 milliards de dollars, dont 40 à 60 % pour les secteurs de la santé, de l'agriculture et de l'alimentation. D'autres secteurs sont également concernés, tels que l'environnement, l'énergie, la bioingénierie (bioréacteurs, enzymes immobilisées, membranes, chromatographie. . . et la chimie. D'un point de vue économique, les biotechnologies sont mieux adaptées à la production de substances à haute valeur ajoutée qu'à celle de produits de gros tonnage. Les produits qui connaissent un développement important sont les enzymes, les amino-acides, les biopolymères. . . Pour les produits de plus gros tonnage, les voies biotechnologiques se heurtent aux réalités économiques, en particulier aux prix comparatifs du pétrole et des céréales ou du sucre. Des procédés, non rentables pour l'instant, ont récemment été mis au point pour des produits tels que l'acrylamide, l'oxyde de propylène, l'hydroquinone, le nylon, le polyphénylène, les diacides. Les Etats-Unis conservent le leadership. Le Japon est sur le point de les rejoindre, tandis que le modèle européen se caractérise par les difficultés de transfert vers l'industrie. Les grandes firmes chimiques, telles que Rhône Poulenc et Impérial Chemical Industries (ICI ont déjà un long passé dans les biotechnologies mais d'autres telles que Monsanto, Du Pont, Mitsubishi. . . , s'y sont engagées récemment. Une analyse de brevets fait apparaître que les sociétés pétrolières s'y intéressent également, pour l'instant de manière moins importante. Leurs préoccupations restent traditionnelles : les polysaccharides, les enzymes immobilisées pour l

  5. Recharge areas and hydrochemistry of carbonate springs issuing from Semmering Massif, Austria, based on long-term oxygen-18 and hydrochemical data evidence

    Science.gov (United States)

    Yehdegho, Beyene; Reichl, Peter

    2002-10-01

    la chimie des carbonates. La pCO2 et la concentration en HCO3- diminuent respectivement d'environ 0,22 unité log (atm) et 38,6 mg/l pour un accroissement de 100 m de l'altitude de recharge. Resumen. Se ha muestreado exhaustivamente el contenido en oxígeno-18 y la hidroquímica de los manantiales existentes en el macizo de Semmering (Austria) con el fin de caracterizar las áreas de recarga y su evolución hidroquímica. Se ha determinado el efecto altitudinal del δ18O con datos isotópicos e hidrogeológicos obtenidos en pequeños manantiales originados en rocas cristalinas que sirven como nivel de referencia; los resultados han sido de -0,27‰ por cada 100 m en la zona Morte del macizo, y de -0,21‰/100 m hacia el Sur. Aplicando estos valores, se ha calculado la altitud promedio a la que se produce su recarga. Para los manantiales de caudal elevado en materiales carbonatados, la altitud de recarga varía entre 1.100 y 1.410 m, cosa que es compatible con el marco topográfico e hidrogeológico de las rocas calizas y dolomíticas Mesozoicas propias del Austroalpino Bajo que los alimenta. La composición hidroquímica de los manantiales carbonatados está dominada por los iones calcio, magnesio, bicarbonato y sulfato. Los manantiales están casi saturados en calcita, pero subsaturados en dolomita, excepto en algunos que parecen hallarse cerca de la saturación. Como caracteriza a los suelos en regiones montañosas, la presión parcial de equilibrio del dióxido de carbono (PCO2) es baja, con valores comprendidos entre 10-3,0 y 10-2,5 atm. A largo plazo, el pH y los valores calculados de los índices de saturación en calcita (SIc) y en dolomita (SId), junto con la PCO2 en equilibrio, evidencian una fuerte estacionalidad; en cambio, las concentraciones de calcio, magnesio y bicarbonato prácticamente no varían. Integrando los resultados de δ18O y de la hidroquímica, se demuestra la variabilidad de la química de aguas subterráneas carbonatadas con respecto a la

  6. Influence of the silica fillers on the ageing of epoxy resins under irradiations; Etude de l'influence des charges de silice sur le vieillissement des resines epoxyde sous irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Benard, F.

    2004-12-17

    stiffening of the nano-metric silica filled resin and the reactions between the resin and the silica surface during irradiations. This study permits to assert that the silica fillers in the epoxy resins protect the network from the irradiations. (author) [French] L'objectif de ces travaux etait d'etudier l'influence de la silice sur le vieillissement des resines epoxyde sous irradiation. Les resines epoxyde obtenues par la reaction d'une polyamine aliphatique (la Triethyltetraamine) avec le prepolymere DGEBA sont difficilement analysables du fait de leur caractere insoluble et infusible. Des modeles chimiques de structures tres voisines de celle de la resine DGEBA/TETA synthetises purs et en presence de silice nanometrique sont analyses par les methodes classiques de chimie organique (RMN du liquide, SEC, Spectrometrie de masse Maldi-tof). Des differences de reactivite des amines primaires et secondaires en presence de silice nanometrique sont mises en evidence. Les analyses des modeles irradies montrent un phenomene majoritaire de coupures de liaisons C-O et C-N accompagnees par la formation d'extremites phenoliques, de terminaisons methylcetone, de fonctions amines primaires et secondaires et notamment d'une double liaison C=C en alpha d'un azote. La RMN {sup 1}H et la RMN {sup 13}C quantitative revelent un effet d'ecran du a la silice et mettent en evidence des reactions entre les especes chimiques reactives creees par les irradiations et la surface de la silice. Les analyses thermiques, thermomecaniques des differentes resines epoxyde en fonction de la dose d'irradiation et du type de silice montrent la diminution de la temperature de transition vitreuse, des temperatures des relaxations et de la densite de reticulation confirmant des phenomenes majoritaires de coupures de liaisons au cours des irradiations. En presence de silice nanometrique, la diminution de la densite de reticulation est ralentie. Ce phenomene peut s

  7. Marine hydrogeology: recent accomplishments and future opportunities

    Science.gov (United States)

    Fisher, A. T.

    2005-03-01

    l'estimation des propriétés à la sub-surface des fonds marins, et des travaux complémentaires ont mis en valeur les mesures de flux, local ou global, de termes « sources » et « pertes », et des liens quantitatifs entre l'hydrogéologie, la chimie, la tectonique, la biologie, et les processus géophysiques. Cet article vise à résumer des résultats sélectionnés parmi un petit nombre d'études, et à décrire plusieurs nouvelles expériences et programmes, qui sont autant d'opportunités pour répondre aux questions fondamentales relatives aux fonds marins, posées ces dernières 20-30 années. La hidrogeología marina es una disciplina científica de amplios alcances que involucra la exploración de interacciones fluido-roca por debajo del fondo del mar. Se han llevado a cabo estudios en centros de expansión del fondo del mar, lugares en medio de una placa, y en ambientes de placa y margen continental. Aunque muchos sitios en el fondo del mar son remotos, existen aspectos de estos sistemas marinos que los hacen particularmente adaptables para análisis hidrológico. Nuevas técnicas y herramientas desarrolladas, y el establecimiento de varios programas multidisciplinarios para exploración oceanográfica, han ayudado a impulsar la hidrogeología marina hacia delante durante las ultimas décadas. La mayor parte del trabajo hidrogeológico marino se ha enfocado en la medición o estimación de propiedades hidrogeológicas dentro del subsuelo superficial, pero trabajo adicionalha enfatizado mediciones de flujos globales y locales, términos de fuente y sumidero de fluidos, y vínculos cuantitativos entre procesos hidrogeológicos, químicos, tectónicos, biológicos y geofísicos. Además de resumir resultados seleccionados de un número pequeño de estudios de caso, este artículo incluye una descripción de varios programas y experimentos nuevos que aportarán oportunidades excepcionales para dirigir preguntas hidrogeológicas fundamentales dentro del

  8. Formulation de fluxants pour bitumes à base d’esters méthyliques d’huiles végétales

    Directory of Open Access Journals (Sweden)

    Alfos Carine

    2003-09-01

    formulations, en présence de bitume, ont été testées au laboratoire d’application industrielle de la société APPIA afin de déterminer l’influence de la nature du bitume (composés asphalténiques, paraffiniques, résines sur le séchage final. Ces tests industriels n’ont pas permis de différencier les comportements des liants EMHV observés en l’absence de bitume. Ainsi l’emploi d’huiles végétales siccatives n’affecte pas significativement la remontée de consistance du liant \\; les résultats obtenus (évolution de la température de ramollissement, TBA, au cours du temps sont quasi identiques à ceux obtenus sur la formule de référence (bitume fluxé en présence de liant pétrochimique. Il semble que la siccativation du bitume soit telle, en présence d’agents siccatifs, que ce phénomène ne nous permette pas d’observer les tendances mises en évidence avec les seuls liants EMHV. Des chantiers réalisés en 2001et 2002 en Haute-Savoie, sur des voies à trafic important, ont montré que la remontée en consistance des formulations proposées pouvait convenir. Les liants EMHV pourront donc couvrir la quasi-totalité des applications. Au total, depuis 1999, plus de 15 000 tonnes de liants anhydres de répandages ont été fabriqués et utilisés avec des résultats similaires à ceux des liants classiques. Ces travaux ont été menés dans le cadre d’un programme Agrice11.1 2 AGRIculture pour la Chimie et l’Energie 1 en partenariat avec Diester Industrie et la société Appia.

  9. Developpement d'une plateforme de calcul d'equilibres chimiques complexes et adaptation aux problemes electrochimiques et d'equilibres contraints

    Science.gov (United States)

    Neron, Alex

    contrainte d'un champ de potentiel électrique est considérée pour l'évaluation des équilibres électrochimiques par des techniques classiques de résolution et fera l'objet de travaux futurs via une technique d'optimisation. Enfin, les résultats obtenus sont comparés avec ceux présents dans la littérature scientifique pour valider le modèle. À terme, le modèle développé devient tin bon moyen de prédire des résultats en éliminant beaucoup de coût en recherche et développement. Les résultats ainsi obtenus sont applicables dans une grande variété de domaines tels que la chimie et l'électrochimie industrielle ainsi que la métallurgie et les matériaux. Ces applications permettraient de réduire la production de gaz à effet de serre en optimisant les procédés et en ayant une meilleure efficacité énergétique. Mots-clés : Systèmes énergétiques avancés, Équilibre thermodynamique, Équilibre contraint, Optimisation, Minimisation de l'énergie libre de Gibbs.

  10. Molecular dynamics simulations of ter-pyridine and bis-triazinyl-pyridine complexes with lanthanide cations; Etude de dynamique moleculaire de complexes de la bis-triazinyl-pyridine (BTP) et de la terpyridine avec des lanthanides(3)

    Energy Technology Data Exchange (ETDEWEB)

    Guilbaud, Ph. [CEA Valrho, (DCC/DRRV/SEMP), 30 - Marcoule (France)

    2000-07-01

    The search for ligands which specifically separate actinides(III) from lanthanides(III) by liquid-liquid extraction has prompted considerable research in the Process Design and Modeling Department ('Service d'Etude et de Modelisation des Procedes'- SEMP). Ligands with soft donor atoms AS) that are able to perform this separation have already been investigated and research is currently under way to improve their performance for high acidic feeds. Theoretical chemistry research is conducted in the Theoretical and Structural Chemistry Laboratory ('Laboratoire de Chimie Theorique et Structurale') to improve our understanding of the complexation and extraction of these cations with such ligands. Theoretical studies were first carried out for the ter-pyridine (TPY) and bis-triazinyl-pyridine (BTP) ligands that display fairly good ability to separate and extract actinide(III) from lanthanide(III) ions. Molecular dynamics simulations were performed on ter-pyridine and bis-triazinyl-pyridine complexes with three lanthanide cations (La{sup 3+}, Eu{sup 3+} and Lu{sup 3+}) for vacuum and for water solutions. These calculations were carried out without counter-ions, with three nitrate (NO{sub 3}{sup -}) ions, and, in the case of ter-pyridine, with three {alpha}-bromo-caprate anions that are likely to be used experimentally as synergistic agents for the separation and extraction of An(III) from Ln(III). Molecular dynamics simulations were first performed for vacuum to evaluate the distances between nitrogen and lanthanide atoms (Ln{sup 3+},N) and intrinsic interaction energies to poly-nitrogenous ligands with or without NO{sub 3} ions, and for both ligands. The (Ln{sup 3+},N) distances decrease and the cation/ligand interaction energies increase along the La{sup 3+}, Eu{sup 3+}, Lu{sup 3+} series, with decreasing Ln(III) ion radii. The introduction of nitrate counter-ions makes the (Ln{sup 3+},N) distances slightly higher, and the TPY/Ln{sup 3+} and BTP

  11. Climate change and employment. A case study of Finland; Changement climatique et emploi. Cas de la Finlande

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-15

    The study has been carried out by a consortium led by the European Trade Union Confederation (ETUC) and the Social Development Agency (SDA), which includes Syndex, the Wuppertal Institute and ISTAS. It was commissioned by the European Commission, DG environment, as a contribution to improve current understanding of the relationship between climate change and employment. The study was also supported financially by seven public bodies: Ministries of Environment of Belgium, Spain, Finland, Italy, United-Kingdom; ADEME and DIAC in France. The first part of the study examines the potential consequences for employment of global warming in Europe - which has already begun and will continue. The main finding is that even moderate climate change will affect economic activity and employment in Europe, with some regions and economic sectors being particularly vulnerable. Increased warming will be likely to have very damaging consequences. The second half of the report considers the challenge for employment of the transition towards a lower CO2 European economy at the horizon 2030, in four key economic sectors: energy production, transport, steel and cement industries, construction/housing. The study considers a number of scenario for a reduction of 40% in CO2 emissions by the year 2030 and what the effects can be on European employment and skills. Case studies of eleven European countries are also analysed. This report is about Finland. [French] La Finlande est le 5e pays europeen en superficie, avec un total de 338.145 km{sup 2}, pour une population de 5,2 millions d'habitants. Le climat finlandais est le plus froid d'Europe, avec des besoins en chauffage pratiquement toute l'annee et des besoins en eclairage tres importants les mois d'hiver, en raison de la duree tres courte du jour. L'industrie est dominee par l'exploitation forestiere et le papier, ainsi que la metallurgie et la chimie, ces industries etant hautement energie-intensives. Ces

  12. Study of cis- and trans-uranium elements by paper chromatography and electrophoresis; Contribution a l'etude des elements cis- et trans-uraniens par chromatographie sur papier et electrophorese

    Energy Technology Data Exchange (ETDEWEB)

    Clanet, F. [Commissariat a l' Energie Atomique, 92 - Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-01-01

    'electrophorese, en chimie minerale, a ete etendu aux elements 90 a 96 en milieux HCl et HNO{sub 3}. Les resultats obtenus portent sur les points suivants: 1) - Caracterisation des etats de valence de Np et de Pu a l'aide de reactions colorees sur les chromatogrammes et les electrophoregrammes. L'alizarine, l'arsenazo-I et le thorin-I permettent de caracteriser la valence IV, tandis que le diphenylcarbazide est specifique de l'etat hexavalent. 2) - Chromatographie sur papier: en utilisant comme eluants des melanges a parts egales de solutions aqueuses de HCl ou de HNO{sub 3} et d'alcools (methanol, ethanol, n-butanol), les R{sub f} des elements 90 a 96 ont ete determines. Certaines conclusions relatives a leur complexation par les ions Cl{sup -} et NO{sub 3}{sup -} ont pu en etre deduites. 3) - Nous avons elabore une technique d'electrophorese sur membrane d'acetate de cellulose afin de separer les especes chargees formees par les elements 90 a 96 dans des solutions HCl et HNO{sub 3} 1 a 12 M. Les courbes de mobilite ont ete tracees. Il decoule de nos resultats que la tendance des elements consideres a former des complexes anioniques s'etablit dans l'ordre des potentiels ioniques, lorsqu'ils sont a l'etat tetravalent; cet ordre est inverse lorsqu'ils sont a la valence III. Les ions Cl{sup -} sont moins complexants que les ions NO{sub 3}{sup -} vis-a-vis de ces elements dans leur etat d'oxydation III et IV, mais on observe le phenomene inverse pour U{sup VI} et Pu{sup VI}. Enfin, la complexation des cations Pu{sup 4+} et PuO{sub 2}{sup 2+} par NO{sub 3}{sup -} suit l'ordre des potentiels ioniques mais a lieu dans l'ordre inverse s'il s'agit d'ions Cl{sup -}. 4) - Diverses applications analytiques sont envisagees: separation les uns des autres des divers elements consideres et separation des etats de valence de Np et de Pu. (auteur)

  13. Production d'éthanol a partir de biomasse lignocellulosique Ethanol Production from Lignocellulosic Biomass

    Directory of Open Access Journals (Sweden)

    Ogier J. C.

    2006-12-01

    Full Text Available Cette étude fait le point des connaissances scientifiques et techniques dans le domaine de la production alcoolique à partir de susbstrats lignocellulosiques. Ce travail, réalisé dans le cadre d'Agrice (Agriculture pour la chimie et l'énergie, est une synthèse bibliographique qui a cherché à identifier les avancées capables de débloquer certains verrous technologiques et économiques liés à ce type de procédé. La biomasse lignocellulosique est un substrat complexe, constitué des trois principales fractions que sont la cellulose, les hémicelluloses et la lignine. Le procédé de production d'éthanol consiste à récupérer par hydrolyse le maximum de sucres issus à la fois des fractions cellulosiques et hémicellulosiques, puis de fermenter ces sucres en éthanol. Les premiers procédés d'hydrolyse utilisés étaient surtout chimiques, mais ils sont peu compétitifs à l'heure actuelle, en raison notamment du coût des réactifs et de la formation de nombreux sous-produits et de composés inhibiteurs rendant les hydrolysats peu fermentescibles. Ils sont désormais concurrencés par les procédés enzymatiques, plus spécifiques et qui permettent de meilleurs rendements d'hydrolyse dans des conditions moins sévères. Cependant, la biomasse lignocellulosique n'est pas directement accessible aux enzymes, et elle doit subir au préalable une phase de prétraitement dont l'objectif est d'améliorer la susceptibilité à l'hydrolyse enzymatique de la cellulose et éventuellement d'hydrolyser la fraction hémicellulosique en sucres monomères. Parmi les nombreuses méthodes de prétraitement qui ont été étudiées, nous en avons identifié trois répondant au mieux aux objectifs précédemment cités : le prétraitement à l'acide dilué, l'explosion à la vapeur avec utilisation d'un catalyseur, et la thermohydrolyse. Ces trois méthodes permettraient d'atteindre des rendements d'hydrolyse enzymatique de la cellulose proches de

  14. Dextran-modified iron oxide nanoparticles

    Institute of Scientific and Technical Information of China (English)

    Jií; Hradil

    2007-01-01

    (18),3995-4021.[11]Horák,D.,& Benedyk,N.(2004).Magnetic poly(glycidyl methacrylate)microspheres prepared by dispersion polymerization in the presence of electrostatically stabilized ferrofluids.Journal of Polymer Science Part A:Polymer Chemistry,42(22),5827-5837.[12]Horák,D.,Semenyuk,N.,& Lednick(y),F.(2003).Effect of the reaction parametrs on the particle size in the dispersion polymerization of 2-hydroxyethyl and glycidyl methacrylate in the presence of a ferrofluid.Journal of Polymer Science Part A:Polymer Chemistry,41(12),1848-1863.[13]Jan(c)a,J.,Ananieva,I.A.,Menshikova,A.Y.,& Evseeva,T.G.(2004).Micro-thermal focusing field-flow fractionation.Journal of Chromatogry B,800(1-2),33-40.[14]Jan(c)a,J.,Berneron,J.-F.,& Boutin,R.(2003).Micro-thermal field-flow fractionation:New high performance method for particle size distribution analysis.Journal of Colloid Interface Science,260(2),317-323.[15]Jan(c)a,J.,& Strnad,P.(2004).Micro and frontal thermal field-flow fractionation:On the shear degradation of ultra-high molar mass polymers.Journal of Liquid Chromatography Related Technology,27(2),193-214.[16]Johann,C.(1998).Asymmetrical field flow fractionation for polymer and particle characterization.GIT Labor-Fachzeitschrift,42,119-120.[17]Jolivet,J.P.,Massart,R.,& Fruchart,J.M.(1983).Synthesis and physicochemical study on nonsurfactant magnetic colloids in aqueous medium.Nouveau Journal De Chimie-New Journal of Chemistry,7(5),325-331.[18]Kaminski,M.D.,& Rosengart,A.J.(2005).Detoxification of blood using injectable magnetic nanospheres:A conceptual technology description.Journal of Magnetism and Magnetic Materials,293(1),398-403.[19]Kramberger,P.,Glover,D.,& Strancar,A.(2003).Application of monolithic columns for the fast separation of nanoparticles.American Biotechnology Laboratory,21(13),27-28.[20]Liu,F.,& Wei,G.(2004).Effect of mobile-phase additives on separation of gold nanoparticles by size-exclusion chromatography.Chromatographia,59(1-2),115-119.[21]Massart,R.(1981).Preparation of

  15. Foreword

    Science.gov (United States)

    Boutron, Claude; Ferrari, Christophe

    2003-05-01

    thank the members of the organising committee and Jerome Nriagu (chairman of the 11th Conference) for helping us to put together the program of this conference. Also, very special thanks are due to Christine Echevet for her continuous and expert efforts to make the Grenoble Conference a success, and to various members of the Laboratoire de Glaciologie et Géophysique de l'Environnement, especially Jocelyne Roquemora. Special thanks are also due to the President of Grenoble Alpes Métropole and the Mayor of the City of Grenoble. Finally, we are very grateful to the various co-sponsors of the conference, especially the Centre National de la Recherche Scientifique (CNRS), the University Joseph Fourier of Grenoble, the Ministère des Affaires Étrangères, the Ministère de l'Écologie et du Développement Durable, the Agence de l'Environnement et de la Maîtrise de l'Énergie (ADEME), Grenoble Alpes Métropole (La Métro), the City of Grenoble, the Region Rhône-Alpes, the Conseil Général de l'Isère, the Association Minéraux, Métaux non ferreux, Santé, Environnement (AMSE), the University of Michigan and the Société Hydrotechnique de France (SHF). Claude BOUTRON and Christophe FERRARI - Conference Co-Chairmen 12th International Conference on Heavy Metals in the Environment, Grenoble, France, 26-30 May 2003 Préface C'est un grand plaisir pour nous d'accueillir la “12e Conférence Internationale sur les Métaux Lourds dans l'Environnement en France Grenoble, au coeur des Alpes. Cette conférence est la 12e du nom, après celles qui ont eu lieu avec beaucoup de succès à Toronto (1975), Londres (1979), Amsterdam (1981), Heidelberg (1983), Athènes (1985), La Nouvelle Orléans (1987), Genève (1989), Edimbourg (1991), Hambourg (1995) et Ann Arbor (2000). Grenoble est l'une des principales ville d'Europe pour la recherche scientifique avec un très grand nombre de chercheurs dans des domaines trés variés, notamment en Physique et Chimie, Mathématiques et

  16. Effects of a fire on runoff and erosion on mediterranean forest soils in SE Spain

    Directory of Open Access Journals (Sweden)

    Mangas, V. J.

    1992-12-01

    el suelo un incremento estadísticamente significativo del contenido en materia orgánica, nitrógeno total, fósforo asimilable y los cationes cambiables: K+, Mg2+ y N+. Por el contrario, hay una disminución de Ca2+ y de la C.I.C. Los valores modificados tras el incendio tienden a recuperar su nivel Inicial en el caso de materia orgánica, fósforo. Na+, Ca2+ y C.I.C. La escorrentía anual tras el incendio es significativamente menor que la del año anterior al incendio, mientras que la escorrentía media es significativamente menor sólo en el caso de no considerar el año más erosivo (Octubre 1987-Septiembre 1988, lo que estaría asociado con una disminución de la precipitación media tras el incendio. Por su parte, la producción de sedimentos del año posterior al incendio no presenta diferencias significativas respecto al año anterior. La disminución en la salida de nutrientes y en el volumen de escorrentía es más acentuada que la disminución en la entrada de nutrientes y en el volumen de la precipitación después del incendio. La salida de nutrientes por escorrentía tras el incendio presenta un rango entre 8 y 35% del año anterior, cuando el volumen sólo representa el 3 %, lo que Implica un aumento en su concentración.
    [fr] On a étudié les flux de ruissellement et de transport du sol, ainsi que sa composition chimique, pendant cinq ans (1985-1990, dans des parcelles d'érosion dans une localité de la Province d'Alicante (SE-Espagne. En septembre 1989, on a brûle la végétation des parcelles, en enregistrant des températures modérées. On a réalisé un suivi de la chimie du sol par trois échantillonnages: avant le feu, le jour suivant et 180 jours plus tard. Le jour après l'incendie, il s'est produit dans le sol une augmentation statistiquement significative de la teneur en matière organique, azote total, phosphore assimilable, et des cations changeables: K

  17. Chemical response to groundwater extraction southeast of Mexico City

    Science.gov (United States)

    Huizar-Alvarez, R.; Carrillo-Rivera, J. J.; Ángeles-Serrano, G.; Hergt, T.; Cardona, A.

    procédure a été appliquée pour caractériser le système d'écoulement souterraine et sa source, les conditions hydrauliques de l'aquifère et la réponse hydraulique des puits considéré. L'analyse de cette information suggérer la présence des systèmes d'écoulement suivantes. (i) local avec18 et 19.5 °C de température, RS de 127-600 mg/L, et Na de 24-178 mg/L, (ii) intermédiaire avec une température de 20 á 22 °C, le RS de 203-940 mg/L et Na 30-370 mg/L, (iii) régional avec 300 à 700 mg/L de RS et 80 à 230 mg/L de Na, une température de 23 à 24.8 °C. Dans le premier cas, l'eau traverse des roches basaltiques, dans le deuxième, des sédiments clastiques avec matière organique de l'aquitard, dans le troisième, des roches volcaniques et calcaires. La chimie de l'eau des quelques puits et sa réponse hydraulique met en évidence l'influence de l'eau de L'aquitard, des effluents de surface et écoulement régional. La conception du régime d'écoulement obtenu, a permis reconnaître les conditions hydrauliques des puits plus correspondantes au contexte hydrogéologique, que si uniquement les données rabattement vs temps auraient été analysé La interpretación conjunta de la gráfica de prueba de bombeo, valores de temperatura y sólidos totales disueltos (STD) del agua subterránea extraída, medidos simultáneamente en campo y la composición química del agua extraída como apoyo adicional; se utilizó como un procedimiento alternativo para interpretar los datos de pruebas de bombeo. Toda esa información fue aplicada para caracterizar el sistema de flujo subterráneo y el origen de éste, las condiciones hidráulicas del acuífero y la respuesta hidráulica de los pozos de extracción. El análisis de la información indica la presencia de: (i) flujo local con temperatura de 18-19.5 °C, STD de 127-600, y Na de 24-178 mg/L (ii) flujo intermedio con temperatura de 20-22 °C, los STD y Na son de (203-940 y 30-370 mg/L), respectivamente; (iii

  18. Contribuição para o conhecimento da intoxicação pelo veneno dos "escorpiões"

    Directory of Open Access Journals (Sweden)

    Octavio de Magalhães

    1928-01-01

    Full Text Available Nous avons travaillé à Bello Horizonte, Etat de Minas, avec le venin de 4 espèces de Scorpions: Tityus bahiensis (C. L. KOCK, 1836. Tityus serrulatus (LUTZ-MELLO, 1922. Tityus dorsomaculatus (LUTZ – MELLO, 1922. Bothriurus (espèce em étude, sur un total de 13.640 individus. Nous avons essayé et observe l’action du venin sur 97 espèces differentes d’êtres vivants – depuis les chlamydozoaires jusqu’à l’«Homo sapiens». Nous avons cherché à déterminer une unité toxique «plus précise, plus régulierè». Les étalons dits «unité vésicule», «unité morsure» sont inconstants et sans rigueur. Tout au plus, peuvent ils server à l’étude de l’action générale du venin, et cela meme, dans certains cas seulement. Nous avons employé la pesée pour determiner l’unité toxique. Ce qui est important pour qui étudie ces sujets ce n’est pás lê nombre de vésicules, mais bien la quantité de venin humide ou desséché qu’elles contiennent. La balance, pour notre travail, est um moyen indicateur de bien plus grande précision que la «vésicule» ou la «morsure». Nous sommes parvenus à prouver qu’il existe une relation constante entre le poid brut des vésicules et la quantité de venin humide ou desséché qu’elles contiennent dans leur intérieur. Donc em pesant les vésicules, nous pesons indirectement le venin. Peu nous importe qu’il y ait 10 ou 100 vésicules. Il nous importe seulement de savoir combien elles pèsent, et de déterminer par ce fait, la quantité proportionnelle de vain pur. La technique générale est la suivante: Nous pesons um certain nombre de vésicules. Nous triturons ensuite, dans um mortier stérilisé et nous emulsionnons, par l’addition consécutive d’eau distillée, stérilisée. Nous filtrons l’émulsion sur le papier filtre employé em chimie, préalablement taré et desséché dans une atmosphere de chlorure de calcium. Après le filtrage on sèche à nouveau les

  19. Modélisation thermodynamique et cinétique des réactions diagénétiques dans les bassins sédimentaires. Présentation du modèle géochimique KINDISP Thermodynamic and Kinetic Modelling of Diagenetic Reactions in Sedimentary Basins. Description of the Geochemical Code Kindisp

    Directory of Open Access Journals (Sweden)

    Clement A.

    2006-11-01

    Full Text Available Le programme thermodynamique et cinétique KINDISP (KINetic of DISsolution and Precipitation simule les interactions minéraux/solutions aqueuses en considérant la dissolution irréversible des réactants et la précipitation réversible ou irréversible des phases secondaires. Les lois générales introduites dans le modèle ont pour base théorique la Thermodynamique des Processus Irréversibles. Les interactions eaux/roches à basse température (25-30 °C sont interprétées théoriquement à l'aide de la Théorie de l'Etat de Transition et de la Chimie de Coordination de Surface. Le mécanisme qui limite la vitesse de dissolution ou de précipitation d'un minéral, c'est-à-dire le mécanisme le plus lent pour les réactions irréversibles successives, est soit la diffusion moléculaire aqueuse d'une entité élémentaire (atome, molécule . . . ou bien la réaction de surface (adsorption-désorption d'une entité élémentaire. A chaque étape du calcul, caractérisé par un incrément de temps (dt, le modèle informatique KINDISP calcule les vitesses de réaction pour chaque minéral réactif dans le système eau-roche. A partir de ce calcul, le modèle compare les vitesses contrôlées par la diffusion moléculaire et par la réaction de surface. Ensuite, KINDISP retient la vitesse la plus lente pour représenter la loi de dissolution d'un minéral réactif primaire ou la loi de précipitation d'une phase néoformée secondaire. La croissance des minéraux secondaires est simulée, soit à l'équilibre thermodynamique, soit en domaine de sursaturation (en nonéquilibre, après une étape de nucléation, lorsque le point de sursaturation critique S* est atteint. Le programme géochimique KINDISP est divisé en deux ensembles : un module de calcul d'équilibre initial de la solution aqueuse appelé EQUILT et un module constitué de la procédure de perturbation par incréments de temps rendant compte de l'évolution géochimique du syst

  20. The use and evolution of the CEA research reactors; Utilisation et evolution des reacteurs de recherche du C.E.A

    Energy Technology Data Exchange (ETDEWEB)

    Rossillon, F.; Chauvez, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    retracent brievement l'histoire de ces reacteurs en montrant ce qu'a ete jusqu'a present leur utilisation, et comment certaines modifications ont permis de les adapter a l'evolution des programmes. Ils precisent egalement les raisons qui ont conduit a l'elaboration du projet de la nouvelle pile OSIRIS, La pile ZOE, la plus ancienne du CEA, est en service au Centre de Fontenay-aux-Roses depuis 1948. Elle est principalement utilisee pour les mesures de section efficace d'absorption du graphite, et pour diverses irradiations de courte duree ne necessitant que des flux peu eleves. La Pile EL2, en service depuis 1952, a permis les premieres etudes liees au refroidissement par gaz. Elle a ete tres utilisee pour la production des radioisotopes et pour de nombreuses experiences de physique, de metallurgie et de physico-chimie - le vieillissement de certaines parties du reacteur a conduit a decider l'arret prochain de cette installation. La Pile EL. 3 a ete tres utilisee pour les experiences de physique et pour l'etude des combustibles. L'adoption d'une nouvelle structure pour le coeur (solution 'Cristal de neige') va permettre d'accroitre considerablement les possibilites de la pile pour les irradiations en neutrons rapides. La pile TRITON-I, piscine de 2 MW, est surtout utilisee pour les irradiations en neutrons rapides et en gamma. Certaines modifications, actuellement en cours, permettront d'accroitre la puissance du reacteur jusqu'a 4 ou 5 MW. Dans un compartiment voisin de TRITON-I est implantee la Pile TRITON-II, de meme structure generale, mais dont la puissance maximum est de 100 kW. TRITON-II est utilisee exclusivement pour les etudes de protections. MELUSINE, pile piscine de 2 MW est en fonctionnement au Centre d'Etudes Nucleaires de Grenoble depuis 1959. Elle a permis l'execution d'un programme important concernant surtout la physique du solide, l'etude fondamentale de

  1. Aspects chimiques de la combustion du charbon pulvérisé. Première partie Chemical Aspects of the Combustion of Pulverized Coal. Part One

    Directory of Open Access Journals (Sweden)

    De Soete G. G.

    2006-11-01

    deux mécanismes totalement différents, par exemple entre le mécanisme d'ignition homogène et le mécanisme d'ignition hétérogène du charbon, avec des conséquences pratiques pour la stabilisation de la flamme industrielle ; autre exemple : la compétition entre les divers mécanismes homogènes de formation d'oxydes d'azote et les mécanismes hétérogènes de leur réduction sur des particules solides de coke, de suie et de cendre. Avec ces idées présentes comme un leitmotiv implicite, on passe en revue les grandes étapes de la flamme industrielle de charbon pulvérisé : la dévolatilisation rapide avec la formation progressive de volatils gazeux, de goudrons et de coke ; la transformation partielle des produits gazeux et liquides de pyrolyse en suies ainsi que leur oxydation en phase gazeuse ; la combustion hétérogène du coke ; l'ignition du charbon et sa dépendance par rapport à des processus critiques homogènes et (ou hétérogènes. Comme exemple typique d'un épiphénomènechimique, on suit la transformation des espèces azotées en NO et en N2, qui se greffe en contrepoint et à chaque pas sur tes différents thèmes successifs de cette symphonie de l'oxydation du charbon. En de nombreux points de cette évolution du charbon à travers la flamme, les connaissances de la chimie de com-bustion en phase gazeuse constituent un instrument utile d'interprétation (par exemple : pour l'oxydation des volatils, pour la discussion des modalités d'ignition. II n'en reste pas moins vrai que la plupart des problèmes chimiques hétérogènes sont bien spécifiques de la flamme de charbon ; leur traitement est rendu ardu à cause de la complexité, évolutive au cours de la combustion, du combustible solide lui-même. It is not easy to obtain a full picture of the multiple chemical phenomena which occur inside a pulverized coal flame. This bibliographie review attempts to give more than just a juxtaposition of data from the recent literature and risks making

  2. Préface

    Science.gov (United States)

    Ouerdane, Youcef; Laporte, Pierre

    2005-06-01

    L'objectif de la série de colloques UVX est de réunir, au rythme d'une fois tous les deux ans, les scientifiques et industriels travaillant dans le domaine du développement des sources de photon de grande énergie (UV, VUV, et X) et de leurs applications. En particulier cette manifestation est l'occasion de faire se rencontrer une communauté très pluridisciplinaire (physique, chimie, biologie, sciences de l'univers) liée à des domaines en forte évolution technologique (lasers et rayonnement synchrotron notamment). Le colloque UVX 2004 s'est tenu au Palais des Congrès de Saint-Étienne (42000) du 7 au 11 juin 2004. La période écoulée depuis l'édition précédente (Oléron 2002) a été particulièrement active dans tous les domaines concernés : grands projets de sources, méthodes de diagnostic au sens large. Une nouvelle fois on constate que le bref et l'ultra-bref ont une place privilégiée, qu'il s'agisse du travail sur les accélérateurs ou sur les lasers qui, bien sûr, dans la course aux temps courts remportent la palme avec la présence de spécialistes du domaine attoseconde. La communauté représentée a la chance d'être en prise directe avec de très grands projets en phase active de réalisation comme le Laser Megajoule (LMJ), la source SOLEIL, et un projet d'ampleur plus modeste mais remarquable dans son domaine : la source LASERIX d'Orsay/Palaiseau. On pourra citer aussi le projet Arc en Ciel qui, lui, est encore au stade de sa définition. - SOLEIL, source de nouvelle génération de rayonnement synchrotron (plateau de Saclay) est dans une phase active de réalisation : achèvement de l'infrastructure en 2005 et injection du 1o faisceau dans l'anneau de stockage prévu également en 2005. Cette source devrait être la meilleure au monde dans le domaine VUV/X mous, tout en restant très polyvalente (brillance, accordabilité, structure temporelle, polarisation) et complémentaire de l'ESRF. Au final on disposera de 21 lignes de lumi

  3. Geología de la margen activa del Perú entre los 3° y 12° de latitud sur

    Directory of Open Access Journals (Sweden)

    1990-01-01

    Full Text Available GEOLOGIE DE LA MARGE ACTIVE DU PEROU ENTRE 3° ET 12° DE LATITUDE SUD. La structure de la marge de type andin du Pérou est bien connue le long de trois profils sismiques multitraces localisés entre 5° et 12º Sud, au large de Paita (Profil CDP3, de Chimbote (CDP2 et Huacho (CDP1, du Nord vers le Sud. Des données additionnelles existent le long de ces transects il s'agit des levers SeaBEAM et SeaMARC II couvrant de vastes surfaces, de dragages et de carottages. Pendant le Leg. 112 du programme ODP, le Joides Resolution a foré 10 sites essentiellement localisés le long des profils CDP1 (679, 680, 681, 682 et 683 et CDP2 (683, 684 et 685. Les résultats du 'Nazca Plate Project' (1972-1980 ont montré que les roches métamorphiques du socle sud-américain s'étendent au moins jusqu'au bord du plateau continental et que l'accrétion de sédiments existe sur le bas de la pente continentale. Le retraitement postérieur des profils sismiques CDP1, CDP2 et CDP3 et les données bathymétriques SeaBEAM ont montré que la limite entre le socle continental de la marge et le prisme d'accrétion est localisé à la limite entre la pente moyenne et la pente inférieure de la marge. Cette limite marque également un changement dans le régime tectonique de la marge qui passe de l'extension pour le haut de pente à la compression vers le bas de pente. Les profils sismiques CDP1 et CDP2 montrent une discordance majeure de l'Eocène sur le socle identique à celle forée aux puits pétroliers Delphin et Ballena. Cette discordance est attribuée à la phase Incaïque (67 Ma à 57 Ma bien connue à terre. Pendant le Leg. 112, l'Eocène a été foré sur trois sites de la pente moyenne et du bas de pente de la marge. Au site 688, l'Eocène présente des faciès marins de faible profondeur d'eau appartenant au plateau continental et à la pente supérieure comme l'indiquent les foraminifères benthiques. Cet Eocène (57 Ma à 40 Ma est recouvert en discordance

  4. EDITORIAL: Announcing the 2009 Measurement Science and Technology Outstanding Paper Awards Announcing the 2009 Measurement Science and Technology Outstanding Paper Awards

    Science.gov (United States)

    Foss, John; Dewhurst, Richard; Fujii, Kenichi; Regtien, Paul

    2010-06-01

    Bretagne, CS 83818, 29238 Brest Cédex 3, France Laboratoire de Métrologie et de Chimie Océanographique, SHOM 13 rue du Châtelier, BP 30316, 29603 Brest Cedex, France The absolute salinity of seawater is an important component in the determination of the ocean's thermodynamic properties. This paper [3] presents a measurement system for very accurate determination of the salinity. The method is based on measuring the refractive index of seawater, a parameter that is related to the salinity. Although the method is essentially simple: using a prism and a PSD for direct measurement of the angle of refraction, the refraction also depends on many more parameters (temperature, pressure, wavelength). Moreover, for obtaining accurate salinity values, a high resolution of the refractive index is required, of the order of 10-7, under all possible conditions. Starting with a list of notations and symbols, the paper follows with an overview of existing methods for salinity measurements and their performances. Next, the principle based on refractometry is introduced, and a theoretical model is presented, comprising a large number of parameters that influence the properties of the refractometer. From this analysis there follows an optimization of the geometry of the device. The sensitivity for salinity and other water parameters are estimated from theory, and verified experimentally. Salinity measurements are compared with those using standard salinometers, and show an uncertainty less than a few 10-3 psu (practical salinity units). The obtained resolution is about 4 × 10-7, which is limited by that of the readout electronics of the PSD. It is demonstrated that this can be further improved to achieve the required resolution lower than 10-7. The authors make clear that their prototype, the length of which is about 12 cm, is an important step to a fully in situ oceanographic salinometer, but further testing is required to confirm reliability. Indeed, the paper does not report on long

  5. Influence of Clays on Borehole Stability : a Literature Survey Part One: Occurence of Drilling Problems. Physico-Chemical Description of Clays and of Their Interaction with Fluids Influence des argiles sur la stabilité des parois de puits : revue bibliographique. Première partie : les problèmes rencontrés lors du forage dans les argiles. Description physico-chimique des argiles et de leur interaction avec les fluides

    Directory of Open Access Journals (Sweden)

    Forsans T.

    2006-11-01

    épandues dans le monde entier, à diverses profondeurs, donc dans des états de compaction et d'évolution diagénétique différents. Leur comportement a conduit à une classification opérationnelle. Des solutions empiriques, destinées à protéger les parois de puits, ont été mises en oeuvre. Toutefois, il apparaît évident que des solutions de caractère général ne peuvent résulter que d'un effort conjoint en mécanique des roches et en physico-chimie : tel est l'objectif du programme STAR. La seconde section est consacrée à la description des réactions physico-chimiques entre les argiles et l'eau. Après avoir décrit les argiles en tant que solides, et plus particulièrement les argiles gonflantesqui ont une charge structurale faible compensée par un cation interfoliaire échangeable, on s'attache au comportement de l'eau qui leur est associée en fonction du degré d'humidité et de la nature et de la concentration des sels dans l'eau. Le gonflement cristallin , limité à une teneur en eau de 50 % environ, et correspondant à des pressions de gonflement de milliers d'atmosphères, est distingué du gonflement osmotique , qui intervient à de plus fortes hydratations, et induit des pressions de l'ordre de la dizaine d'atmosphères au maximum. L'influence spécifique des cations comme le potassium et le calcium est décrite. Des exemples de comportement à la compaction, fonction de la nature des argiles et des cations sont décrits. Il apparaît qu'une description très précise des conditions de départ et du déroulement des phénomènes est indispensable pour l'interprétation, et qu'elle est malheureusement absente dans nombre de publications. La troisième section traite de la description mécanique du comportement des roches argileuses lors du forage. La possibilité de modéliser ce comportement dépend de l'acquisition des paramètres pertinents, et du choix du modèle : le modèle Cam Clay, qui utilise une loi élasto-plastique est donné en exemple

  6. Production of Olefins and Higher Hydrocarbons by Thermal Coupling of Methane Production d'oléfines et d'hydrocarbures supérieurs par couplage thermique du méthane

    Directory of Open Access Journals (Sweden)

    Weill J.

    2006-11-01

    'oxychloration d'éthylène pour un prix de pétrole brut de l'ordre de 23 à 27 $ par baril, alors que les autres procédés de production d'acétylène ne le sont jamais. Si l'hydrogène ne peut être valorisé chimiquement, le seuil de compétitivité passe à 30 $ par baril. En ce qui concerne la production d'éthylène, les figures 12a, 12b montrent que le procédé de pyrolyse du méthane devient compétitif pour un prix de pétrole brut compris entre 30 et 35 $ par baril. On remarque également qu'une unité de capacité plus faible avec une valorisation complète de l'hydrogène est plus intéressante qu'une unité de forte capacité sans utilisation chimique complète de l'hydrogène. Bien que pour un développement technologique de cet ampleur, de nombreux travaux soient encore nécessaires, les excellents résultats déjà obtenus à l'aide d'une technologie totalement innovatrice devraient permettre au couplage thermique du méthane de répondre à certains challenges futurs des pays industrialisés et de la France en particulier comme l'obtention de bases pétrochimiques non pétrolières, la réponse au besoin futur en hydrogène, le redémarrage d'une chimie fondée sur l'acétylène.

  7. 国外文献速报

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

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  8. Preface

    Science.gov (United States)

    Gorse, D.; Boutard, J.-L.

    2002-09-01

    The Symposium on “Structural materials for Hybrid systems: A challenge in metallurgy" was held during the “Journées d'Automne 2001" of the “Société Française de Métallurgie et de Matériaux", Paris from October 29 through 31, 2001. The editors of this volume, D. Gorse and J.-L. Boutard, would like to acknowledge GDR GEDEON, CEA - Direction de l'énergie Nucléaire, CNRS - Département des Sciences Chimiques, et Centre d'études de Chimie Métallurgique for sponsoring this symposium. This symposium was divided into three sessions dealing with i) thermodynamics, intergranular penetration and liquid metal embrittlement, ii) irradiation effects in structural materials and iii) compatibility of structural materials with lead alloys in relation with R& D studies for MEGAPIE. The intent of this symposium was to provide a forum for discussing the most recent results obtained in the frame of the materials research program of the “Groupement De Recherche (GDR) GEDEON". Special emphasis was given to all factors susceptible to affect the durability of structural materials for spallation targets, like irradiation effects under proton and neutron mixed spectrum, Liquid Metal Corrosion (LMC) and Embrittlement (LME). The material research program of GEDEON is a joint CEA-CNRS venture. In 1997, the GDR GEDEON gave opportunity to metallurgists and nuclear physicists of both organizations to collaborate for validating the concept of Pb-Bi spallation targets as a key component for Accelerator-Driven Systems (ADS). Historically, since 1995, GDR GEDEON has promoted ADS, also called Hybrid System, as an option for waste management. The starting point of the material program was the 1st GEDEON Workshop on “Materials For Hybrid Systems" held in Paris in 1997, where reference materials of the 9-12 Cr martensitic steels series were selected: EM10 (9Cr-1Mo) and the modified 9Cr-1Mo, T91 (9Cr-1Mo-V-Nb). However, besides their specific concern for ADS, our studies are also of

  9. Multiphase Production. Representation of Thermodynamic Properties of Methanol by Different Equations of State Production polyphasique. Représentation des propriétés thermodynamiques du méthanol à partir de différentes équations d'état

    Directory of Open Access Journals (Sweden)

    Peneloux A.

    2006-11-01

    quation bipolynomiale à cinquante et un paramètres a bien sûr l'avantage de calculer précisément les tensions de vapeur, les grandeurs volumiques à saturation et hors saturation, les capacités calorifiques, les seconds coefficients du viriel, la vitesse du son, les enthalpies dans les conditions de saturation et hors saturation. Conclusion : Ce travail sur le méthanol a été effectué dans le cadre du programme de recherche EvE (Évacuation des Effluents qui associe l'IFP, Elf et Total avec le soutien du CEP&M (Comité d'Études Pétrolières et Marines sur l'ensemble des recherches liées à la Production Polyphasique : modèles hydrauliques, physico-chimie et thermodynamique, instrumentation /débitmétrie triphasique et pompage polyphasique. Après les progrès récents en modélisation hydraulique (modèle transitoire TACITE, il devient urgent d'améliorer, aussi, nos outils de prédiction du comportement thermodynamique et physico-chimique des divers types d'effluents pétroliers, même les plus complexes, et ceci, dans toutes les conditions de transport, même les plus difficiles, en tenant compte, en particulier, des risques de formation d'hydrates et de leur contrôle, . . . d'où l'intérêt de l'étude du méthanol. La sûreté de fonctionnement des installations de production polyphasique ne saurait être garantie sans la poursuite des diverses recherches en cours sur le comportement des effluents en cours de transport, domaine qui ne peut pas être considéré comme totalement maîtrisé et qui, dans certains cas, peut conduire à des situations potentiellement dangereuses.