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Sample records for tcherenkov atmospherique celeste

  1. CELESTE an atmospheric Cherenkov telescope for high energy gamma astrophysics

    CERN Document Server

    Paré, E; Bazer-Bachi, R; Bergeret, H; Berny, F; Briand, N; Bruel, P; Cerutti, M; Collon, J; Cordier, A; Cornebise, P; Debiais, G; Dezalay, J P; Dumora, D; Durand, E; Eschstruth, P T; Espigat, P; Fabre, B; Fleury, P; Gilly, J; Gouillaud, J C; Gregory, C; Herault, N; Holder, J; Hrabovsky, M; Incerti, S; Jouenne, A; Kalt, L; Legallou, R; Lott, B; Lodygensky, O; Manigot, P; Manseri, H; Manitaz, H; Martin, M; Morano, R; Morineaud, G; Muenz, F; Musquere, A; Naurois, M D; Neveu, J; Noppe, J M; Olive, J F; Palatka, M; Pérez, A; Quebert, J; Rebii, A; Reposeur, T; Rob, L; Roy, P; Sans, J L; Sako, T; Schovanek, P; Smith, D A; Snabre, P; Villard, G

    2002-01-01

    CELESTE is an atmospheric Cherenkov telescope based on the sampling method which makes use of the de-commissioned THEMIS solar electrical plant in the French Pyrenees. A large (2000 m sup 2) mirror surface area from 40 independent heliostats followed by a secondary optic, a trigger system using analog summing techniques and signal digitization with 1 GHz flash ADCs make possible the detection of cosmic gamma-rays down to 30 GeV. This paper provides a detailed technical description of the CELESTE installation.

  2. El Sistema de Referencia Celeste convencional de la IAU

    Science.gov (United States)

    Arias, E. F.

    La Unión Astronómica Internacional (IAU) recomendó la adopción de un nuevo sistema de referencia celeste baricéntrico cuyo plano fundamental y origen de ascensiones rectas estén próximos, respectivamente, al ecuador y equinoccio dinámicos J2000.0. El nuevo sistema de referencia estará materializado por las posiciones J2000.0 de radiofuentes extragalácticas determinadas con la técnica de interferometría de larga línea de base (VLBI). El Working Group on Reference Frames de la IAU (WGRF) decidió adoptar (Grasse, 1995) al sistema de referencia celeste extragaláctico del Servicio Internacional de la Rotación Terrestre (IERS) como futuro sistema de referencia celeste convencional bajo el nombre International Celestial Reference System (ICRS) y encomendó su mantenimiento futuro al IERS. El marco de referencia que materializará al ICRS contiene posiciones precisas J2000.0 de más de 600 radiofuentes extragalácticas. Las coordenadas fueron ajustadas en una única solución VLBI en la cual se incluyeron todas las observaciones realizadas hasta octubre de 1995 con la técnica de adquisición de datos VLBI Mark III. Para minimizar los errores sistemáticos que pueden afectar la calidad del marco de referencia se introdujeron mejoras sustanciales en la modelización y en la selección de datos. Un subconjunto de objetos del marco de referencia se utilizó para referir las posiciones estelares determinadas con el satélite astrométrico Hipparcos al ICRS.

  3. Measurement of the blazar Mrk421 flux above 60 GeV with the CELESTE experiment

    International Nuclear Information System (INIS)

    Le Gallou, R.

    2001-11-01

    The CELESTE experiment is based on an ancient solar plant that has been turned into a detector able to detect the particle showers triggered by the interactions of high energy cosmic photons with the earth atmosphere nuclei. The purpose of the CELESTE experiment is to study the emissions of photons by cosmic objects like supernovae remnants, pulsars or active cores of galaxies such as blazars. Blazars are very interesting objects to study because they allow us to investigate matter that is in extreme conditions and to probe a very far past. The aim of this work has been to develop methods for the analysis of the data collected by CELESTE and to validate them. A specific effort has been achieved for the selection of efficient hadronic rejection criteria in order to optimize the sensitivity of the detector. The physics of the detector is detailed from the particle showers to the data analysis. The detector acceptance has been assessed through Monte-Carlo simulations that have been shown that the detection threshold is 30 GeV at the triggering point and 60 GeV after the analysis cuts. The validation tests have been performed on the Crab nebula that is a standard in gamma astronomy for its stability and intensity. CELESTE has been operating since November 1999 in a satisfactory way and has accumulated data on 4 blazars among them Mrk421. Several bursts have been detected on Mrk421 and an average photon flux has been determined. A correlation has been deduced from the activity detected by CELESTE and the activities in the TeV and X ranges which agrees with the simulations

  4. Relevamiento total del hemisferio sur celeste en la frecuencia de 1420 MHz

    Science.gov (United States)

    Bava, J. A.; Colomb, F. R.; Hurrel, E.; Larrarte, J. J.; Sanz, A. J.; Testori, J. C.; Reich, P.; Reich, W.; Wielebinski, R.

    En el presente artículo se describe el relevamiento del cielo en el Hemisferio Sur Celeste en la frecuencia de 1420 MHz para declinaciones δde 30 metros de diámetro del IAR. Este relevamiento posee igual sensibilidad (3xr.m.s=50 mK) que el realizado en el Hemisferio Norte con el radiotelescopio de 25 metros de Stockert de la Universidad de Bonn, operado por el Max-Planck Institute für Radioastronomie ( Reich W., 1982, A&ASS 48, 219; Reich P. and Reich W., 1986, A&ASS 63, 205). Con los datos obtenidos por ambos radiotelescopios se posee una base de datos de todo el cielo en esta frecuencia. En esta publicación presentamos los detalles del sistema receptor, técnicas de observación y reducción de datos, calibración y discusión de los errores en los resultados.

  5. La divinidad celeste/solar en el panteón céltico peninsular

    Directory of Open Access Journals (Sweden)

    Rubén Abad Lara

    2008-01-01

    Full Text Available En la Hispania prerromana existió una divinidad suprema con carácter celeste y solar de tipo similar a la que se rindió culto en el resto de la Europa indoeuropea. El análisis de algunas piezas del arte celtibérico, nos revela que esa divinidad principal era representada bajo la forma de un jinete a caballo con lanza. La iconografía muestra que ese dios, uno de cuyos nombres pudo ser Lugus, tomó parte de numerosos mitos que le relacionaban con la guerra, la fertilidad y el mundo funerarioIn preroman Spain there was a supreme divinity with solar and heavenly roles, very similar to the divinities worshiped in the rest of the indoeuropean Europe. The analysis of some celtiberian pieces of art, revealed to us that this principal divinity was depicted in the form of a horseman on his horse and holding a spear. The iconography shows that this God, one of his names could be Lugus, took part in many myths which linked him to war, fertility and the funerary world.

  6. Sobre o uso das séries de Puiseux em mecanica celeste

    Science.gov (United States)

    Miloni, O. I.

    2003-08-01

    Neste trabalho é apresentada uma demonstração do uso dos diferentes desenvolvimentos em séries para as equações de perturbação em Mecânica Celeste no marco Hamiltoniano. Em trabalhos clássicos como os de Poincaré (Poincaré, 1893) por exemplo, já esta planteado o uso de potências não inteiras no pequeno parâmetro, o que evidencia a não analiticidade das funções quando uma ressonância ocorre. Nestes trabalhos os desenvolvimentos são na raíz quadrada da massa de Júpiter (o pequeno parâmetro). Mais recentemente (Ferraz-Mello, 1985) outros tipos de desenvolvimentos foram aplicados modificando substancialmente as ordens de grandeza e a velocidade de convergência das séries. Com esta abordagem, os desenvolvimentos foram expressados em termos da raíz cúbica do pequeno parâmetro. Neste trabalho apresentamos um enfoque geral, onde os diferentes tipos de desenvolvimentos em séries de Puiseux (Valiron, 1950) são obtidos a partir da aplicação de Teorema de Preparação de Weierstrass (Goursat, 1916) considerando a equação de Hamilton-Jacobi como uma equação algébrica. Os resultados são aplicados ao problema restrito dos três corpos em ressonância de primeira ordem e, dependendo da grandeza da excentricidade do asteróide em relação à de Júpiter, obtemos os diferentes desenvolvimentos, em raíz quadrada ou raíz cúbica da massa de Júpiter.

  7. Reconstruction of the characteristics of gamma showers and contribution to the data analysis of the experiment Celeste

    International Nuclear Information System (INIS)

    Herault, N.

    2000-04-01

    The detection of high energy gamma radiation is an important tool for the study of violent events occurring somewhere in the galaxies and produced by pulsars or active nuclei. Since the beginning of the nineties, a new technology is used: the ground-based detection of Cerenkov light emitted by the air shower issuing from very high energy gamma radiation. Celeste (Cerenkov low energy sampling and timing experiment) is the last of a series of experiments: Asgat, Themistocle and Cat, that have been performed on the site of the decommissioned solar plant Themis. Alike Asgat and Themistocle, Celeste is based on the same method of parting the light wave front but uses the important 54 m 2 surface mirrors of the ancient solar plant to collect it. The processing of the different accurate moments at which the Cerenkov light has reached each mirror allows the reconstruction of the tail of the shower. This installation is expected to collect more Cerenkov light and to allow physicists to reach the 30 to 300 GeV energy range that has been till now largely unexplored in gamma astronomy. The first chapter is dedicated to the various methods for detecting gamma radiation, either satellite on-board experiments or ground-based detection systems. The second chapter presents the experiment Celeste and explains how this experiment could bring new information about astrophysical concerns. The third chapter deals with the detailed technical description of the installation, especially the optical and electronic systems. The fourth chapter is dedicated to the reconstruction of gamma showers, the determination of their direction is a delicate problem. The fifth chapter presents the characteristics of the background noise coming from hadronic showers. The sixth chapter is dedicated to the calibration of the detector and it gives its first preliminary results. (A.C.)

  8. Scattering of Light by Colloidal Aluminosilicate Particles Produces the Unusual Sky-Blue Color of R?o Celeste (Tenorio Volcano Complex, Costa Rica)

    OpenAIRE

    Castell?n, Erick; Mart?nez, Mar?a; Madrigal-Carballo, Sergio; Arias, Mar?a Laura; Vargas, William E.; Chavarr?a, Max

    2013-01-01

    Río Celeste (Sky-Blue River) in Tenorio National Park (Costa Rica), a river that derives from the confluence and mixing of two colorless streams--Río Buenavista (Buenavista River) and Quebrada Agria (Sour Creek)--is renowned in Costa Rica because it presents an atypical intense sky-blue color. Although various explanations have been proposed for this unusual hue of Río Celeste, no exhaustive tests have been undertaken; the reasons hence remain unclear. To understand this color phenomenon, we ...

  9. An effective model for fermion dark matter. Indirect detection of supersymmetric dark matter in astronomy with the CELESTE Telescope; Modele effectif de matiere noire fermionique. Detection indirecte de matiere noir supersymetrique en astronomie avec le Telescope CELESTE

    Energy Technology Data Exchange (ETDEWEB)

    Lavalle, Julien [Ecole Doctorale des Sciences Fondamentales, Universite Blaise Pascal, Aubiere (France)

    2004-07-01

    The purpose of this thesis is to discuss both phenomenological and experimental aspects of Dark Matter, related to its indirect detection with gamma-ray astronomy. In the MSSM framework, neutralinos arise as natural candidates to non-baryonic and Cold Dark Matter, whose gravitational effects manifest in the Universe at different scales. As they are Majorana particles, they may in principle annihilate in high density regions, as the centres of galaxies, and produce gamma rays. Nevertheless, the expected fluxes are basically low compared to experimental sensitivities. After estimating gamma fluxes from M31 and Draco galaxies in the MSSM scheme, we first generalize the MSSM couplings by studying an effective Lagrangian. We show that the only constraint of imposing a relic abundance compatible with recent measurements obviously deplete significantly the gamma ray production, but also that predictions in this effective approach are more optimistic for indirect detection than the MSSM. In a second part, we present the indirect searches for Dark Matter performed with the CELESTE Cherenkov telescope towards the galaxy M31. We propose a statistical method to reconstruct spectra, mandatory to discriminate classical and exotic spectra. The M31 data analysis enables the extraction of an upper limit on the gamma ray flux, which is the first worldwide for a galaxy in the energy range 50-500 GeV, and whose astrophysical interest goes beyond indirect searches for Dark Matter. (author)

  10. Basic model of fermion dark matter. Indirect detection of supersymmetric dark matter in {gamma} astronomy with the CELESTE telescope; Modele effectif de matiere noire fermionique. Detection indirecte de matiere noire supersymetrique en astronomie {gamma} avec le telescope CELESTE

    Energy Technology Data Exchange (ETDEWEB)

    Lavalle, J

    2004-10-15

    The purpose of this thesis is to discuss both phenomenological and experimental aspects of Dark Matter, related to its indirect detection with gamma-ray astronomy. In the MSSM (Minimal Supersymmetric Standard Model) framework, neutralinos arise as natural candidates to non-baryonic and Cold Dark Matter, whose gravitational effects manifest in the Universe at different scales. As they are Majorana particles, they may in principle annihilate in high density regions, as the centres of galaxies, and produce gamma rays. Nevertheless, the expected fluxes are basically low compared to experimental sensitivities. After estimating gamma fluxes from M31 and Draco galaxies in the MSSM scheme, we first generalize the MSSM couplings by studying an effective Lagrangian. We show that the only constraint of imposing a relic abundance compatible with recent measurements obviously deplete significantly the gamma ray production, but also that predictions in this effective approach are more optimistic for indirect detection than the MSSM. In a second part, we present the indirect searches for Dark Matter performed with the CELESTE Cherenkov telescope towards the galaxy M31. We propose a statistical method to reconstruct spectra, mandatory to discriminate classical and exotic spectra. The M31 data analysis enables the extraction of an upper limit on the gamma ray flux, which is the first worldwide for a galaxy in the energy range 50-500 GeV, and whose astrophysical interest goes beyond indirect searches for Dark Matter. (author)

  11. Melqart-Herakles matando al Toro Celeste en una placa ebúrnea de Medellín

    Directory of Open Access Journals (Sweden)

    Almagro-Gorbea, Martín

    2002-12-01

    Full Text Available An ivory plaque found in the Tartessian necropolis from Medellin (Badajoz, Spain, dated about 600 B.C., shows a hero with a Phygian helmet killing a bull. The iconography of this scene can be interpreted a Phoenician-Tartessian myth of «Melqart killing de Heaven's Bull», which could be a precedent of the well-known Greek myth of «Herakles and the Cretan Bull». This ivory plaque is interesting not only for classical iconography but also to show the deep relation between the Phoenician and the Tartessian mythology.En la necrópolis tartésica orientalizante de Medellín ha aparecido una placa con una escena de tauromaquia fechada hacia el 600 a.C. con un personaje con gorro frigio que apuntilla a un toro. Su análisis iconográfico permite interpretarla como un posible mito de «Melqart dando muerte al Toro Celeste», probable precedente del mito griego de Heracles y el Toro de Creta. Además de su interés para la mitología clásica, este marfil confirma la profunda interrelación entre la mitología y las creencias tartésicas y fenicias.

  12. An effective model for fermion dark matter. Indirect detection of supersymmetric dark matter in astronomy with the CELESTE Telescope

    International Nuclear Information System (INIS)

    Lavalle, Julien

    2004-01-01

    The purpose of this thesis is to discuss both phenomenological and experimental aspects of Dark Matter, related to its indirect detection with gamma-ray astronomy. In the MSSM framework, neutralinos arise as natural candidates to non-baryonic and Cold Dark Matter, whose gravitational effects manifest in the Universe at different scales. As they are Majorana particles, they may in principle annihilate in high density regions, as the centres of galaxies, and produce gamma rays. Nevertheless, the expected fluxes are basically low compared to experimental sensitivities. After estimating gamma fluxes from M31 and Draco galaxies in the MSSM scheme, we first generalize the MSSM couplings by studying an effective Lagrangian. We show that the only constraint of imposing a relic abundance compatible with recent measurements obviously deplete significantly the gamma ray production, but also that predictions in this effective approach are more optimistic for indirect detection than the MSSM. In a second part, we present the indirect searches for Dark Matter performed with the CELESTE Cherenkov telescope towards the galaxy M31. We propose a statistical method to reconstruct spectra, mandatory to discriminate classical and exotic spectra. The M31 data analysis enables the extraction of an upper limit on the gamma ray flux, which is the first worldwide for a galaxy in the energy range 50-500 GeV, and whose astrophysical interest goes beyond indirect searches for Dark Matter. (author)

  13. Basic model of fermion dark matter. Indirect detection of supersymmetric dark matter in γ astronomy with the CELESTE telescope

    International Nuclear Information System (INIS)

    Lavalle, J.

    2004-10-01

    The purpose of this thesis is to discuss both phenomenological and experimental aspects of Dark Matter, related to its indirect detection with gamma-ray astronomy. In the MSSM (Minimal Supersymmetric Standard Model) framework, neutralinos arise as natural candidates to non-baryonic and Cold Dark Matter, whose gravitational effects manifest in the Universe at different scales. As they are Majorana particles, they may in principle annihilate in high density regions, as the centres of galaxies, and produce gamma rays. Nevertheless, the expected fluxes are basically low compared to experimental sensitivities. After estimating gamma fluxes from M31 and Draco galaxies in the MSSM scheme, we first generalize the MSSM couplings by studying an effective Lagrangian. We show that the only constraint of imposing a relic abundance compatible with recent measurements obviously deplete significantly the gamma ray production, but also that predictions in this effective approach are more optimistic for indirect detection than the MSSM. In a second part, we present the indirect searches for Dark Matter performed with the CELESTE Cherenkov telescope towards the galaxy M31. We propose a statistical method to reconstruct spectra, mandatory to discriminate classical and exotic spectra. The M31 data analysis enables the extraction of an upper limit on the gamma ray flux, which is the first worldwide for a galaxy in the energy range 50-500 GeV, and whose astrophysical interest goes beyond indirect searches for Dark Matter. (author)

  14. Roles of crustacean hyperglycaemic hormone in ionic and metabolic homeostasis in the Christmas Island blue crab, Discoplax celeste.

    Science.gov (United States)

    Turner, Lucy M; Webster, Simon G; Morris, Stephen

    2013-04-01

    There is a growing body of evidence implicating the involvement of crustacean hyperglycaemic hormone (CHH) in ionic homeostasis in decapod crustaceans. However, little is known regarding hormonally influenced osmoregulatory processes in terrestrial decapods. As many terrestrial decapods experience opposing seasonal demands upon ionoregulatory physiologies, we reasoned that these would make interesting models in which to study the effect of CHH upon these phenomena. In particular, those (tropical) species that also undergo seasonal migrations might be especially informative, as we know relatively little regarding the nature of CHHs in terrestrial decapods, and hormonally mediated responses to seasonal changes in metabolic demands might also be superimposed or otherwise integrated with those associated with ionic homeostasis. Using Discoplax celeste as a model crab that experiences seasonal extremes in water availability, and exhibits diurnal and migratory activity patterns, we identified two CHHs in the sinus gland. We biochemically characterised (cDNA cloning) one CHH and functionally characterised (in terms of dose-dependent hyperglycaemic responses and glucose-dependent negative feedback loops) both CHHs. Whole-animal in situ branchial chamber (22)NaCl perfusion experiments showed that injection of both CHHs increased gill Na(+) uptake in a seasonally dependent manner, and (51)Cr-EDTA clearance experiments demonstrated that CHH increased urine production by the antennal gland. Seasonal and salinity-dependent differences in haemolymph CHH titre further implicated CHH in osmoregulatory processes. Intriguingly, CHH appeared to have no effect on gill Na(+)/K(+)-ATPase or V-ATPase activity, suggesting unknown mechanisms of this hormone's action on Na(+) transport across gill epithelia.

  15. Prevalence and correlates of 'agua celeste' use among female sex workers who inject drugs in Ciudad Juarez, Mexico.

    Science.gov (United States)

    Morris, Meghan D; Case, Patricia; Robertson, Angela M; Lozada, Remedios; Vera, Alicia; Clapp, John D; Medina-Mora, Maria Elena; Strathdee, Steffanie A

    2011-09-01

    Agua celeste, or "heavenly water", is the street name for a sky-blue colored solvent reportedly inhaled or ingested to produce an intoxicating effect. Study aims were to (1) describe prevalence of agua celestse (AC) use, and (2) identify correlates of lifetime and recent use of AC use among female sex workers who also inject drugs (FSW-IDUs) in northern Mexico. Between 2008 and 2010, baseline data from FSW-IDUs≥18 years old living in Tijuana or Ciudad Juarez participating in a longitudinal behavioral intervention were analyzed using logistic regression. Among 623 FSW-IDUs (307 from Tijuana and 316 from Ciudad Juarez (CJ)), 166 (26%) reported ever using AC, all of whom lived in CJ. Among the CJ sample, lifetime prevalence of AC use was 53%, median age of first use was 16 years (IQR: 14-23), and 10% reported it as their first abused substance. Ever using AC was independently associated with ever being physically abused and younger age, and was marginally associated with initiating injection drug use and regular sex work at age eighteen or younger. Among those ever using AC, 70/166 (42.2%) reported using it within the last 6 months, which was independently associated with using drugs with clients before or during sex, being on the street more than 8h per day, and younger age. We observed considerable geographic variation in the use of AC in northern Mexico. Future studies exploring factors influencing use, its precise formulation(s), and its potential health effects are needed to guide prevention and treatment. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  16. Scattering of light by colloidal aluminosilicate particles produces the unusual sky-blue color of Río Celeste (Tenorio volcano complex, Costa Rica.

    Directory of Open Access Journals (Sweden)

    Erick Castellón

    Full Text Available Río Celeste (Sky-Blue River in Tenorio National Park (Costa Rica, a river that derives from the confluence and mixing of two colorless streams--Río Buenavista (Buenavista River and Quebrada Agria (Sour Creek--is renowned in Costa Rica because it presents an atypical intense sky-blue color. Although various explanations have been proposed for this unusual hue of Río Celeste, no exhaustive tests have been undertaken; the reasons hence remain unclear. To understand this color phenomenon, we examined the physico-chemical properties of Río Celeste and of the two streams from which it is derived. Chemical analysis of those streams with ion-exchange chromatography (IC and inductively coupled plasma atomic emission spectroscopy (ICP-OES made us discard the hypothesis that the origin of the hue is due to colored chemical species. Our tests revealed that the origin of this coloration phenomenon is physical, due to suspended aluminosilicate particles (with diameters distributed around 566 nm according to a lognormal distribution that produce Mie scattering. The color originates after mixing of two colorless streams because of the enlargement (by aggregation of suspended aluminosilicate particles in the Río Buenavista stream due to a decrease of pH on mixing with the acidic Quebrada Agria. We postulate a chemical mechanism for this process, supported by experimental evidence of dynamic light scattering (DLS, zeta potential measurements, X-ray diffraction and scanning electron microscopy (SEM with energy-dispersive spectra (EDS. Theoretical modeling of the Mie scattering yielded a strong coincidence between the observed color and the simulated one.

  17. Caracterisation environnementale des emissions atmospheriques d'une source fixe et creation d'un outil de gestion dynamique =

    Science.gov (United States)

    Fournier, Marie-Claude

    Une caracterisation des emissions atmospheriques provenant des sources fixes en operation, alimentees au gaz et a l'huile legere, a ete conduite aux installations visees des sites no.1 et no.2. La caracterisation et les calculs theoriques des emissions atmospheriques aux installations des sites no.1 et no.2 presentent des resultats qui sont en dessous des valeurs reglementaires pour des conditions d'operation normales en periode hivernale et par consequent, a de plus fortes demandes energetiques. Ainsi, pour une demande energetique plus basse, le taux de contaminants dans les emissions atmospheriques pourrait egalement etre en dessous des reglementations municipales et provinciales en vigueur. Dans la perspective d'une nouvelle reglementation provinciale, dont les termes sont discutes depuis 2005, il serait souhaitable que le proprietaire des infrastructures visees participe aux echanges avec le Ministere du Developpement Durable, de l'Environnement et des Parcs (MDDEP) du Quebec. En effet, meme si le principe de droit acquis permettrait d'eviter d'etre assujetti a la nouvelle reglementation, l'application de ce type de principe ne s'inscrit pas dans ceux d'un developpement durable. L'âge avance des installations etudiees implique la planification d'un entretien rigoureux afin d'assurer les conditions optimales de combustion en fonction du type de combustible. Des tests de combustion sur une base reguliere sont donc recommandes. Afin de supporter le processus de suivi et d'evaluation de la performance environnementale des sources fixes, un outil d'aide a la gestion de l'information environnementale a ete developpe. Dans ce contexte, la poursuite du developpement d'un outil d'aide a la gestion de l'information environnementale faciliterait non seulement le travail des personnes affectees aux inventaires annuels mais egalement le processus de communication entre les differents acteurs concernes tant intra- qu'inter-etablissement. Cet outil serait egalement un bon

  18. Protection of personnel against atmospheric contamination by plutonium in the laboratory (1963); Protection du personnel contre la contamination atmospherique par le plutonium, dans les laboratoires (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Feliers, P; Pomarola, J; Risselin, A [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1963-07-01

    Various problems about measurement of atmospheric contamination by plutonium in laboratories are considered. In particular are studied sampling methods, continuous measurement for alarm, criteria used for fixation of the concentrations to be measured, sensitivity of apparatus and effects of natural atmospheric contamination. The means actually available for measurement of contamination and their limits of use are briefly analysed. (authors) [French] Les differents problemes a resoudre pour realiser un controle satisfaisant de la contamination atmospherique par le plutonium, dans les laboratoires, sont abordes. On etudie en particulier les differents modes d'echantillonnage, le controle continu en vue de l'alarme, les criteres qui servent a la fixation des concentrations a mesurer, la sensibilite a donner aux moyens de mesure, les difficultes provenant de la contamination atmospherique naturelle. Les moyens actuellement disponibles pour le controle de la contamination et leurs moyens limites d'emploi sont analyses sommairement. (auteurs)

  19. Atmospheric corrosion of uranium-carbon alloys; Corrosion atmospherique des alliages uranium-carbone

    Energy Technology Data Exchange (ETDEWEB)

    Rousset, P; Accary, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    The authors study the corrosion of uranium-carbon alloys having compositions close to that of the mono-carbide; they show that the extent of the observed corrosion effects increases with the water vapour content of the surrounding gas and they conclude that the atmospheric corrosion of these alloys is due essentially to the humidity of the air, the effect of the oxygen being very slight at room temperature. They show that the optimum conditions for preserving U-C alloys are either a vacuum or a perfectly dry argon atmosphere. The authors have also established that the type of corrosion involved is a corrosion which 'cracks under stress' and is transgranular (it can also be intergranular in the case of sub-stoichiometric alloys). They propose, finally, two hypotheses for explaining this mechanism, one of which is illustrated by the existence, at the fissure interface, of corrosion products which can play the role of 'corners' in the mono-carbide grains. (authors) [French] Les auteurs etudient la corrosion des alliages uranium-carbone de composition voisine du monocarbure; ils montrent que l'importance des effets de la corrosion observee augmente avec la teneur en vapeur d'eau du milieu gazeux ambiant et concluent que la corrosion atmospherique de ces alliages est due essentiellement a l'humidite de l'air, l'action de l'oxygene de l'air etant tres faible a la temperature ambiante. Ils indiquent que les conditions optimales de conservation des alliages U-C sont le vide ou une atmosphere d'argon parfaitement desseches. D'autre part, les auteurs etablissent que le type de corrosion mis en jeu est une corrosion 'fissurante sous contrainte', transgranulaire (pouvant egalement etre intergranulaire dans le cas d'alliages sous-stoechiometriques). Ils proposent enfin deux hypotheses pour rendre compte de ce mecanisme, dont l'une est illustree par la mise en evidence, a l'interface des fissures, de produits de corrosion pouvant jouer le role de 'coins' dans les grains de

  20. El ecoturismo: quimera o realidad de desarrollo en la Reserva de la Biosfera Ría Celestún, México

    Directory of Open Access Journals (Sweden)

    Manuel Jesús Pinkus Rendón

    2015-01-01

    Full Text Available El ecoturismo es una alternativa que puede incidir positivamente en la conservación de los recursos naturales y en la economía de las comunidades. En este trabajo se reflexiona sobre el impacto del ecoturismo en comunidades ubicadas en la Reserva de la Biosfera Ría Celestún, Península de Yucatán. Se realizaron entrevistas semiestructuradas a los prestadores de servicios y se observaron diferencias en la percepción de la conservación de los recursos naturales dependiendo de la capacitación recibida. Se advirtió una falta de coordinación entre las autoridades que influía negativamente en el manejo sustentable de la reserva y en las cooperativas turísticas.

  1. Poincaré, creador de los métodos todavía modernos en las ecuaciones diferenciales y en la mecánica celeste

    Directory of Open Access Journals (Sweden)

    Delshams i Valdés, Amadeu

    2004-08-01

    Full Text Available Con motivo del sesquicentenario del nacimiento de Henri Poincaré, resulta impresionante comprobar la influencia actual de su obra, así como el gran adelanto de sus métodos e ideas respecto a las de los científicos coetáneos. En esta conferencia se repasan algunas de sus contribuciones principales a las ecuaciones diferenciales y ala mecánica celeste, y se discute el papel central que tuvo en éstas su memoria sobre el problema de tres cuerpos presentada en 1889 a un concurso para conmemorar el sexagésimo aniversario del Rey Óscar II de Suecia y Noruega.…

  2. Teorí­as de primer y segundo orden sobre el potencial de ciertas figuras de equilibrio de cuerpos celestes

    Science.gov (United States)

    Gumbau, Manuel Forner

    2010-11-01

    Uno de los problemas que aborda la Mecánica Celeste es la determinación de las figuras de equilibrio de los cuerpos celestes. Para investigar su solución mediante métodos directos, se precisa evaluar el potencial generado por su autogravitación, el generado por su fuerza centrí­fuga y el generado por la fuerza de atracción entre los cuerpos. Los métodos clásicos de Finlay y Kopal que afrontan estos problemas, para determinar el potencial autogravitatorio en las configuraciones de equilibrio, emplean desarrollos en serie de los potenciales interior y exterior del potencial autogravitatorio. Estos métodos incurren en el error de suponer la convergencia en capas donde resulta cuestionable dicha convergencia para estos desarrollos en serie. En este trabajo se han elaborado unos algoritmos que contemplan toda la casuí&stica y que permiten una manipulación efic iente del producto de polinomios de Legendre, del producto de funciones asociada s de Legendre y del producto de armónicos esféricos como combinacióon lineal de ellos mismos, respectivamente. Se han obtenido, para primer y segundo orden en las amplitudes, los desarrollos correctos para los potencial es interior y exterior del potencial autogravitatorio para configuraciones de equilibrio aisladas, y , en primer orden de amplitudes, los mismos potenciales para los sistemas binarios próximos. Se ha elaborado un método analítico, en primer orden respecto de las amplitudes, para la determinación del potencial de marea en sistemas binarios próximos en el cual se manifiesta la forma de la componente secundaria del sistema

  3. Gamma astronomy above 30 GeV. A new method for identifying cosmic gamma rays from the ground based detector Celeste; Astronomie gamma au-dessus de 30 GeV. Une nouvelle methode d'identification des rayons gamma cosmiques a partir du sol avec le detecteur CELESTE

    Energy Technology Data Exchange (ETDEWEB)

    Manseri, H

    2004-03-15

    Celeste is an atmospheric Cherenkov telescope based on the reconversion of the Themis solar facility, located in the Eastern Pyrenees. The mirrors, named heliostats, recover the Cherenkov light emitted by the electromagnetic shower created by gamma-rays in the atmosphere. The Celeste experiment was designed during the 90's to cover the 30-300 GeV energy range and to fill the gap between satellites and imaging atmospheric Cherenkov telescopes. In 2000, we attained our goal with the detection of the Crab Nebula and those of the active galactic nucleus Markarian 421. This thesis presents the work accomplished since then to improve the sensitivity of our instrument by studying the detector and by developing a new analysis. Despite the very bad weather conditions, a new detection of the Crab Nebula is presented here which validates the principle of the new analysis. This manuscript ends with the study of the data sample taken on two Active Galactic Nuclei, the blazars Markarian 421 and 1ES1426+428. (author)

  4. The distribution, atmospheric transfer, and assessment of krypton-85; Distribution, transfert atmospherique et bilan du krypton-85

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-06-01

    Techniques for sampling and measuring krypton-85 have been developed which allowed to determine its geographical distribution. From its use as a tracer, an evaluation of the air masses which cross over the subtropical fronts has been derived. Besides, the stratospheric character of air pollution by krypton-85 at the level of the antarctic soil has been shown out. Levels of krypton-85 seem to point out to an underestimation of the assessment of nuclear explosion fission energies as adopted by the United Nations Scientific committee on the effects of atomic radiation and emphasize the need to set limits as soon as possible to the amounts of krypton-85 released to the atmosphere by fuel-reprocessing plants. (author) [French] La mise au point de techniques de prelevement et de mesure du krypton-85 atmospherique a permis de determiner sa repartition geographique. De son utilisation comme traceur on deduit une evaluation des masses d'air qui traversent les fronts subtropicaux. Par ailleurs, le caractere stratospherique de la pollution de l'air par le krypton-85 au niveau du sol antarctique est mis en evidence. Le bilan du krypton-85 semble reveler une sous-estimation du bilan des energies de fission des explosions adopte par le Comite scientifique des Nations Unies et souligne la necessite de limiter des que possible les quantites de krypton-85 rejetees dans l'atmosphere par les usines de traitement de combustibles irradies. (auteur)

  5. Breaking the Gender Binary: Feminism and Transgressive Female Desire in Lucía Etxebarria's Beatriz y los cuerpos celestes and La Eva futura/La letra futura

    Directory of Open Access Journals (Sweden)

    Lauren Applegate

    2013-06-01

    Full Text Available The popular texts of Spanish author Lucía Etxebarria have created a polemical social phenomenon in contemporary Spain for their blatant depiction of a world of violence, drugs, and experimental sex of the late-millennium youth culture of Generación X. These topics, along with Etxebarria's public persona and feminist ideology, have fomented much public criticism and given rise to discussion of the current status of feminism, gender norms, and women's authorship in Spain today. This article analyzes Etxebarria's novel Beatriz y los cuerpos celestes and her collection of feminist essays La Eva futura/La letra futura, demonstrating that Etxebarria's depiction of female desire and sexuality within their cultural context challenges the notion that feminism has no more to achieve and breaks the gender binary by imagining a gender-anonymous world. Beatriz delves into the life of the title character, a young woman whose experience with a dissolute social culture and her attempts to understand herself cause her to question stereotypical standards of womanhood and eroticism and to declare that she fits into no such preconceived notions. Beatriz is a literary inscription of Etxebarria's feminist ideology as posited in La Eva futura, insofar as both these texts blur the line between feminism and postfeminism and engage with consumerist culture and identity. Moreover, they construe a philosophy that pushes the boundaries of normative discourse by misciting hegemonic notions of femininity and sexuality and creating the potential for change through such mis-repetition of hegemonic discourse. Ultimately, Etxebarria's work strives for a transgressive, unbound, and fluid female desire that is in continuous reconstruction and defies heteronormative definition.

  6. Measurement of the gamma ray flux between 50 and 350 GeV from the Mrk 501 Blazar with the experiment CELESTE

    International Nuclear Information System (INIS)

    Brion, E.

    2005-10-01

    The blazar Mrk 501 has a non-thermal emission spectrum with 2 components. The first one, located between radio waves and X-rays, is due to the synchrotron emission of the magnetized jet, while the second one, emitted in the high energy gamma-ray domain, is still not fully understood. Until 1999, this last domain had only been covered between 100 MeV and 4 GeV as well as above 300 GeV. This energy gap was filled by the creation of the CELESTE experiment, recording Cherenkov emission produced by gamma-rays between 50 and 350 GeV penetrating the atmosphere. Mrk 501, which has a variable emission, was observed in 2000 and 2001, and was detected in 2000. A flux has been calculated which constrains the high energy emission models, presented in this thesis. Crab nebula flux measurements validate the method since this source is the standard candle for atmospheric Cherenkov telescopes. Analysis cuts for Mrk 501 are determined using data from the blazar Mrk 421, which has nearly the same declination as Mrk 501. Finally, improved detector simulations were used to calculate the effective area of the instrument, taking the atmosphere quality into account, yielding the flux for Mrk 501 during observations taken between April and June 2000. This flux was compared with a synchrotron self-Compton emission model and with data taken in X-rays. It shows that Mrk 501 was slightly more active during this period compared to the remainder of the year and to the year 2001. A flux upper limit is calculated for other measurements. This is the first measurement in the energy range 50 - 350 GeV (this range represents the limits in energy for which the trigger rate, that is the convolution between the source spectrum and the effective area of the instrument, is higher than 20% of the trigger maximum). It helps to constrain the position of the inverse Compton emission maximum and tends to favor, in this particular case, X- and gamma-ray emission processes from 2 different electron populations

  7. Use of hydraulic and aerial mock up to study atmospheric pollution; L'utilisation des maquettes aeriennes et hydrauliques pour l'etude de la pollution atmospherique

    Energy Technology Data Exchange (ETDEWEB)

    Facy, L; Perrin De Brichambaut, C; Doury, A; Le Quinio, R

    1962-07-01

    -Cyr. Les resultats obtenus sont essentiellement de deux natures: - le modele mathematique de diffusion turbulente dans l'atmosphere, deduit de la theorie de Sutton, et que nous utilisons generalement, s'est trouve correctement verifie, qualitativement et quantitativement, dans tous les cas ou les conditions de validite de la theorie etaient remplies par l'experience; - les essais qualitatifs de visualisations photographiques ou cinematographiques ont apporte des precisions interessantes sur des phenomenes pratiquement inaccessibles aux calculs, lies notamment a l'influence des obstacles et des conditions de rejet. D'une maniere generale, on peut affirmer que les etudes de pollution atmospherique peuvent etre menees a bien par des experimentations sur maquettes, et que dans certains cas ces experimentations ne pourront jamais etre remplacees par des modeles mathematiques purs. (auteurs)

  8. Study of atmospheric tritium transfers in lettuce: kinetic study, equilibrium and organic incorporation during a continuous atmospheric exposure; Etude des transferts du tritium atmospherique chez la laitue: Etude cinetique, etat d'equilibre et integration du tritum sous forme organique lors d'une exposition atmospherique continue

    Energy Technology Data Exchange (ETDEWEB)

    Boyer, C.

    2009-11-30

    This thesis has explored the mechanisms of tritium 'absorption and incorporation in a human-consumed plant, lettuce (Lactuca sativa L.), due to atmospheric exposure. Foliar uptake appears to play a key role in absorption of tritium as tissue free water tritium. Whatever the development stage and the light conditions, the specific activity in tissue free water reaches that of water vapour in air in several hours. The specific activity ratio is then about 0, 4. The time to reach equilibrium in soil is over 24 hours in most cases: the specific activity ratio ranges then 0, 01 to 0, 26. Incorporation rate of tissue free water tritium as organically-bound tritium has been estimated to 0, 13 to 0, 16 % h-l in average over the growing period of the plant, but marked variations are observed during growth. In particular, a significant increase appeared at the exponential growth stage. Deposition and diffusion of tritium in soil lead to significant OBT activities in soil. Results globally indicate equilibrium between the different environmental compartments (air, soil, plant). However, some experiments have revealed high OBT concentrations regarding atmospheric level exposure and ask for a possible phenomenon of local tritium accumulation in OBT for particular conditions of exposure. (author) [French] Ce travail de these a concerne l'etude des phenomenes d'absorption et d'incorporation sous forme organique du tritium dans un vegetal de consommation courante, la laitue (Lactuca sativa L.), en reponse a une exposition atmospherique. Il apparait que la voie foliaire joue un role primordial dans l'absorption du tritium au sein de l'eau tissulaire des plants. Quels que soient le stade de developpement des plants et les conditions d'eclairement, le temps necessaire pour atteindre l'equilibre des concentrations dans l'eau libre et dans la vapeur d'eau de l'air est de plusieurs heures; le rapport des concentrations est alors de

  9. Study of the behaviour of artificial radioactive aerosols. Applications to some problems of atmospheric circulation (1963); Etude du comportement dcs aerosols radioactifs artificiels. Applications a quelques problemes de circulation atmospherique (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-11-15

    The aim of this work, consists in the examination of the behaviour of radioactive aerosols produced in the atmosphere by nuclear explosions, in order to deduce the most general laws governing atmospheric circulation and diffusion. After having given a general table of the radioactive aerosols present the authors consider the validity and the precision of the measurement methods and the concentration of the aerosols at ground level and in the upper atmosphere, as well as their deposition on the ground. The existence is thus demonstrated of a tropospheric equatorial barrier and of discontinuous and seasonal aspects of stratosphere-troposphere transfers. The role is shown of precipitations and dry auto-filtration in the lower atmosphere cleaning processes. This work makes it possible to describe the general behaviour of dust from the stratosphere, and to improve the total radioactive contamination of the globe. (author) [French] L'objectif de ce travail consiste a examiner le comportement des aerosols radioactifs introduits dans l'atmosphere par les explosions nucleaires, pour en deduire les lois les plus generals de la circulation et diffusion atmospheriques. Apres avoir dresse un tableau d'ensemble des aerosols radioactifs presents, on examine la validite et la precision des methodes de mesure de leur concentration, au niveau du sol et en haute atmosphere, ainsi que de leur depot a la surface du sol. On met ainsi en evidence l'existence d'une barriere equatoriale tropospherique; l'aspect discontinu et saisonnier des transferts stratosphere-troposphere; le role des precipitations et de l'auto-filtration seche, dans les processus de nettoyage de la basse atmosphere. Ces etudes permettent de decrire le comportement general des poussieres d'origine stratospherique et d'ameliorer le bilan de la contamination radioactive du globe. (auteur)

  10. Study of the behaviour of artificial radioactive aerosols. Applications to some problems of atmospheric circulation (1963); Etude du comportement dcs aerosols radioactifs artificiels. Applications a quelques problemes de circulation atmospherique (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-11-15

    The aim of this work, consists in the examination of the behaviour of radioactive aerosols produced in the atmosphere by nuclear explosions, in order to deduce the most general laws governing atmospheric circulation and diffusion. After having given a general table of the radioactive aerosols present the authors consider the validity and the precision of the measurement methods and the concentration of the aerosols at ground level and in the upper atmosphere, as well as their deposition on the ground. The existence is thus demonstrated of a tropospheric equatorial barrier and of discontinuous and seasonal aspects of stratosphere-troposphere transfers. The role is shown of precipitations and dry auto-filtration in the lower atmosphere cleaning processes. This work makes it possible to describe the general behaviour of dust from the stratosphere, and to improve the total radioactive contamination of the globe. (author) [French] L'objectif de ce travail consiste a examiner le comportement des aerosols radioactifs introduits dans l'atmosphere par les explosions nucleaires, pour en deduire les lois les plus generals de la circulation et diffusion atmospheriques. Apres avoir dresse un tableau d'ensemble des aerosols radioactifs presents, on examine la validite et la precision des methodes de mesure de leur concentration, au niveau du sol et en haute atmosphere, ainsi que de leur depot a la surface du sol. On met ainsi en evidence l'existence d'une barriere equatoriale tropospherique; l'aspect discontinu et saisonnier des transferts stratosphere-troposphere; le role des precipitations et de l'auto-filtration seche, dans les processus de nettoyage de la basse atmosphere. Ces etudes permettent de decrire le comportement general des poussieres d'origine stratospherique et d'ameliorer le bilan de la contamination radioactive du globe. (auteur)

  11. A new scheme to treat the numerical Tcherenkov instability for electromagnetic particle simulations

    International Nuclear Information System (INIS)

    Assous, F.; Degond, P.; Segre, J.; Degond, P.

    1997-10-01

    The aim of this paper is to present a new explicit time scheme for electromagnetic particle simulations. The main property of this new scheme, which depends on a parameter, is to reduce and in some cases to suppress numerical instabilities that can appear in this context, and are widely described in the literature. Other numerical properties are also investigated, and a numerical example is finally given to illustrate our purpose. This scheme is expected to be useful in the field of plasma modelling. (authors)

  12. CELESTE: an atmospheric Cherenkov telescope for high energy gamma astrophysics

    Czech Academy of Sciences Publication Activity Database

    Paré, E.; Balauge, B.; Bazer-Bachi, R.; Bergeret, H.; Berny, F.; Briand, N.; Bruel, P.; Cerutti, M.; Collon, J.; Cordier, A.; Cornbise, P.; Debiais, G.; Dezalay, J. P.; Dumora, D.; Durand, E.; Eschstruth, P.; Espigat, P.; Fabre, B.; Fleury, P.; Gilly, J.; Gouillaud, J. C.; Gregory, C.; Hérault, N.; Holder, J.; Hrabovský, Miroslav; Incerti, S.; Jouenne, A.; Kalt, L.; LeGallou, R.; Lott, B.; Manigot, P.; Neveu, J.; Olive, J. F.; Palatka, Miroslav; Perez, A.; Rebii, A.; Rob, L.; Sans, J. L.; Schovánek, Petr; Villard, G.

    2002-01-01

    Roč. 490, - (2002), s. 71-89 ISSN 0168-9002 R&D Projects: GA MŠk LN00A006 Institutional research plan: CEZ:AV0Z1010920 Keywords : gamma-ray astronopy * atmospheric Cherenkov detector Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.167, year: 2002

  13. Birds and the urban ecology of Potchefstroom / Nicoleen Celeste Smith

    OpenAIRE

    Smith, Nicoleen Celeste

    2004-01-01

    Human activities cause drastic changes in the environment, such as the fragmentation of habitats, which is the greatest threat to the world's biodiversity and biogeography. By using birds to study habitat changes, it is possible that the type of habitat qualities that may still be possible near and in cities could be determined. It is possible that by improving the quality or conditions of habitats for birds, habitat qualities for other fauna would also improve. Birds are al...

  14. Consequences of Windscale accident (October 1957) and study of the validity of the Sutton's mathematical model of atmospheric diffusion (1960); Etude des consequences de l'accident de Windscale (Octobre 1957) et de la validite du modele mathematique de diffusion atmospherique de Sutton (1960)

    Energy Technology Data Exchange (ETDEWEB)

    Doury, A [Commissariat a l' Energie Atomique (S.C.R.G.R.) Saclay (France).Centre d' Etudes Nucleaires; Martin, J J [Electricite de France (EDF)(S.L.P.R.), 37 - Chinon (France)

    1960-07-01

    The reactor accident that happens at the number 1 pile of Windscale in 1957 was followed by a discharge of radioactive products into the atmosphere from the 1.X.1957 at 4.30 PM to the 12.X.1957 at 3.10 PM. On october the 11{sup th} it was possible to say that there was no more risk either of external irradiation or inhalation. But in adopting a M.A.C. of 0,1 {mu}curie of iodine 131 per litre of milk, the Authority had to control the milk delivery till november 23{sup rd} on a 500 km{sup 2} area. On the other hand, this exceptional accident permit to verify that Sutton's atmospheric diffusion model could give an easy means to foresee, with a sufficient approximation, the consequences of a dispersion of radioactive products into the atmosphere. (author) [French] L'accident survenu a la pile numero 1 de Windscale en 1957 a entraine l'emission de matieres radioactives dans l'atmosphere du 10 octobre a 16h30 au 12 octobre a 15h10. Le 11 octobre, on pouvait dire qu'il n'y avait plus de risque d'irradiation externe ni de danger par inhalation. Mais en adoptant une C.M.A. de 0,1 {mu}curie d'iode 131 par litre de lait, les autorites ont du reglementer la consommation du lait jusqu'au 23 novembre sur une etendue d'environ 500 km{sup 2}. D'autre part, cet accident exceptionnel a permis de verifier que le modele de diffusion atmospherique de Sutton pouvait fournir un moyen commode de prevoir avec une approximation suffisante les consequences d'une dispersion de produits radioactifs dans l'atmosphere. (auteur)

  15. Pollution atmospherique par emission de gaz d'echappement des ...

    African Journals Online (AJOL)

    The objective of the present work is to study the air pollution generated by the gases of exhaust in the city of Porto-Novo to Benin. The quantification of the different pollutants or particles given out on the one hand by the vehicles, and the determination of the level of the pollution of every particle on the other hand, allowed us ...

  16. Air pollution and floristic biodiversity; Pollution atmospherique et biodiversite floristique

    Energy Technology Data Exchange (ETDEWEB)

    Grub, A.; Bungener, P.; Contat, F.; Nussbaum, S.; Endtner, V.; Fuhrer, J. [Station Federale de Recherches en Agroecologie et Agriculture (FAL), Liebefeld-Berne (Switzerland). Institut de Recherches en Protection de l' Environnement et en Agriculture (IUL)

    1999-06-01

    The number of reports on negative effects of air pollution on biodiversity is increasing. Here, examples from the literature are presented which concern effects of fluoride, deposition of nitrogen, and ozone. Today, nitrogen loads and levels of tropospheric ozone seem to be most relevant forms of air pollution affecting species diversity of the flora. Results from recent investigations of ozone effects at Liebefeld indicate that the loss of floristic diversity in permanent meadows is possible because of the high relative sensitivity of some typical species. Further studies will be necessary to validate the results obtained from experiment with single plants at the level of the intact plant community in the field, and to identify the critical level of ozone to protect the floristic biodiversity of meadows. (authors)

  17. Measurement of the crab flux above 60 GeV with the celeste Cerenkov telescope

    Czech Academy of Sciences Publication Activity Database

    Naurois De, M.; Holder, J.; Bazer-Bachi, R.; Bergeret, H.; Bruel, P.; Cordier, A.; Debais, G.; Dezalay, J. P.; Dumora, D.; Durand, E.; Eschstruth, P.; Espigat, P.; Fabre, B.; Fleury, P.; Hérault, N.; Hrabovský, Miroslav; Incerti, S.; Le Gallou, R.; Moenz, F.; Musquére, A.; Olive, J. F.; Paré, E.; Québert, J.; Rannot, R. C.; Reposeur, T.; Rob, L.; Roy, P.; Sako, T.; Schovánek, Petr; Smith, D. A.; Snabre, P.; Volte, A.

    2002-01-01

    Roč. 566, - (2002), s. 343-357 ISSN 0004-637X R&D Projects: GA ČR GA202/97/1181 Institutional research plan: CEZ:AV0Z1010920 Keywords : gamma ray: observations * ISM:individual (Crab Nebula) * pulsar :individual (Crab Pulsar ) * supernova remnants Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 6.187, year: 2002

  18. Indivíduos celestes: cristianismo e parentesco em um grupo nativo da Amazônia

    Directory of Open Access Journals (Sweden)

    Aparecida Vilaça

    2007-07-01

    Full Text Available Esse artigo parte da oposição entre sociedades individualistas e relacionais desenvolvida por Joel Robbins para a análise do conflito gerado pela adoção do cristianismo entre os Urapmin da Papua Nova Guiné. No caso dos Wari' amazônicos, a percepção aguda da centralidade da noção de indivíduo no cristianismo a eles apresentado, e do conflito potencial entre esta noção e os valores relacionais de sua sociedade, os levou ao engenhoso descolamento desses indivíduos para o mundo póstumo, situando-os em um céu constituído por hiper-indivíduos, sem qualquer relação entre si.This article sets out from the opposition between individualist and relational societies developed by Joel Robbins in his analysis of the conflict generated by the adoption of Christianity among the Urapmin of Papua New Guinea. In the case of the Amazonian Wari', their acute perception of the centrality of the notion of the individual in the version of Christianity presented to them, and the potential conflict between this notion and the relational values of their own society, led them to the ingenious solution of dislocating these individuals to the posthumous world, situating them in a heaven of hyper-individuals without any relationship to each other.

  19. A ring imaging Cherenkov counter for the AMS experiment: simulation, prototype and perspective; Un imageur d'anneaux tcherenkov pour l'experience AMS: simulation, prototypie et perspectives physiques

    Energy Technology Data Exchange (ETDEWEB)

    Thuillier, T

    2000-05-01

    The AMS spectrometer is scheduled to be installed on the International Space Station ISS in 2003. The detector will be equipped with a Ring Imaging Cherenkov Counter (RICH). The report starts with a presentation of the physics goals of AMS and continues with a description of the spectrometer. The RICH detector response and event reconstruction is then described and detailed. The presentation proceeds with a simulation study of cosmic ray nuclei expected with the AMS RICH counter in space. Next, the thesis reports on the research and development of a RICH prototype built and tested in the period 1997-1999 in the Grenoble Institute of Nuclear Science (ISN). The response of the prototype and its calibration are described. Tests have been performed with cosmic rays at ground and ion beam at GSI-Darmstadt. The data analysis of the test campaigns is then presented and compared with simulation results. Finally, a dedicated test of Albedo particle Rejection Power of the RICH detector is reported. (author)

  20. Primordial black holes, cosmic rays and instrumental developments for the Cerenkov imager of the AMS space experiment; Trous noirs primordiaux, rayonnement cosmique et developpements instrumentaux pour l'imageur Tcherenkov de l'experience spatiale AMS

    Energy Technology Data Exchange (ETDEWEB)

    Boudoul, G

    2003-09-01

    The AMS experiment will be implemented on the International Space Station in 2006 for 3 years. It will study cosmic rays and should open a new window to look for dark matter and antimatter in the Universe. This work is, first, devoted to the experimental study of the Cherenkov (RICH) detector of AMS which will determine with a good accuracy the velocity and electric charge of the incoming particles. The chosen photodetectors, the electronic tests, the general schematics, the prototypes operating (including beam tests at CERN) are described into the details. The second part is made of theoretical investigations of some cosmic ray physics problems and to a possible exotic source: evaporating primordial black holes. The astrophysical, cosmological and gravitational (including speculative string gravity approaches) consequences of their possible existence are reviewed in details. (author)

  1. Gaseous atmospheric pollution. Gas measurement; Pollution atmospherique gazeuse. Mesure des gaz

    Energy Technology Data Exchange (ETDEWEB)

    Toupance, G [Paris-12 Univ., 94 - Creteil (France); Person, A [Laboratoire d' Hygiene de la Ville de Paris, 75 (France); Le Moullec, Y; Masclet, P; Perros, P E

    2004-09-01

    This article deals with the majority of pollutants which are present in gaseous phase in the low layer of the troposphere, of the proximity of sources to the distant areas where are in weak traces persisting substances or sub-products induced by photochemical reactions. The compounds described in this article are of interest for various reasons: either they are source tracers, or they draw attention for their impact on health or/and ecosystem. Their follow-up can also be in other approaches such as the understanding of reactional mechanisms and the support to modeling of the phenomena. Thereby, the range of the covered concentrations is very large: if the preoccupations are in most of the cases to answer to detection limits of about the ppb, for some substances, the requirements can be harder and we have then to orient oneself to techniques able to quantify at the level of ppt, sometimes less. Some pollutants are qualified of 'semi-volatile', that is to say they are the property to be present in gaseous phase and in particles in suspension in air. (O.M.)

  2. Set of counts by scintillations for atmospheric samplings; Ensemble de comptages par scintillations pour prelevements atmospheriques

    Energy Technology Data Exchange (ETDEWEB)

    Appriou, D.; Doury, A.

    1962-07-01

    The author reports the development of a scintillation-based counting assembly with the following characteristics: a photo-multiplier with a wide photo-cathode, a thin plastic scintillator for the counting of beta + alpha (and possibility of mounting an alpha scintillator), a relatively small own motion with respect to activities to be counted, a weakly varying efficiency. The authors discuss the counting objective, present equipment tests (counter, proportional amplifier and pre-amplifier, input drawer). They describe the apparatus operation, discuss the selection of scintillators, report the study of the own movement (electron-based background noise, total background noise, background noise reduction), discuss counts (influence of the external source, sensitivity to alpha radiations, counting homogeneity, minimum detectable activity) and efficiencies.

  3. Sanitary impact of the particulate atmospheric urban pollution; Impact sanitaire de la pollution atmospherique urbaine particulaire

    Energy Technology Data Exchange (ETDEWEB)

    Sentissi, M.

    1999-03-22

    The pollution of particulates origin is one of the principle actual problem relative to air quality. In France, the fine particulates come from industry and automobile traffic, especially, the diesel vehicles. The most worrying characteristic is their fineness, that allow them to stay in suspension during a long time and penetrate into pulmonary alveoli, with toxic elements at their surface such metals, acids, polycyclic aromatic hydrocarbons. The objective of this work is to take stock of epidemiology and toxicology studies evaluating the sanitary impact of particulates in suspension. (N.C.)

  4. Controle d'attitude d'un lanceur en phase atmospherique approche par applications gardiennes

    Science.gov (United States)

    Dubanchet, Vincent

    In a first phase, the modelling process underlines the presence of highly time varying parameters during the ascent, due to a fast mass variation along with propellant consumption. Linearizing the dynamical equations at six main flight instants yields linear time invariant models to be considered during control design. Each of them is to be stabilized by one control law, while respecting given specifications. The synthesis becomes even more complex when the bending modes are taken into account. Moreover, scheduling appears necessary to deal with the time variations. Indeed it is shown that no single gain setting is able to respect all the specifications along the trajectory. Furthermore, increasing complexity when modelling a whole launch vehicle pushes one to consider the model's errors and uncertainties. They represent a major issue in this study since it is asked to ensure the nominal performances in a robust fashion. Owing to their properties, guardian maps appear to be the most suitable tool to deal with such a problem of scheduling with robust performances. In light of this, the development of synthesis methods based on guardian maps is the main contribution of the project. It appears that actual state of the art in this field is focused on theoretical issues, whereas practical ones could be improved. Two approches are presented in the memoire. The first one is based on a graphical approach consisting in drawing the vanishing locus of guardian maps. A program using image analysis techniques is devised to check automatically which gain settings satisfy the constraints. The second one is based on an optimisation procedure involving guardian maps. Starting with the open loop system, the iterative process proposed ends up with a satisfactory gain setting for the closed-loop. These methods are tried and tested for the launch vehicle, with specifications from ASTRIUM-ST. Their practical application is motivated by the system complexity, the different kinds of constraints and the essential need for robustness. Many restrictions that finally bring about the interest and the efficiency of guardian maps for such a problem.

  5. Atmospheric pollution and health. An introduction; Pollution atmospherique et sante une introduction

    Energy Technology Data Exchange (ETDEWEB)

    Zmirou, D. [Universite-Faculte de Medecine, 38 - Grenoble (France)

    1996-12-31

    Physiological observations and pollution measurements allowed for the study of short and long term respiratory effects of tropospheric ozone and fine particulate pollution on man, depending on age and health factors. Risk reduction policies towards air quality, and criteria issues for atmospheric pollution control and abatement measures, are discussed

  6. Atmospheric muons reconstruction with Antares; Reconstruction de muons atmospheriques avec ANTARES

    Energy Technology Data Exchange (ETDEWEB)

    Melissas, M

    2007-09-15

    The ANTARES collaboration is building a neutrino telescope in the Mediterranean Sea. This detector contains 900 photomultiplier tubes, dispatched on 12 lines, in order to detect Cerenkov light from muon induced by neutrino interactions in the the vicinity of the detector. Currently the first 5 lines have been deployed. A first task consists in studying the stability of the detector calibration, which is a necessary step to understand the detector response. Then we studied optical properties of water, for this we developed a reconstruction method dedicated to LED Beacon. The extracted parameters are compatible with earlier measurements. A quality criteria to reject badly reconstructed track has been developed based on the likelihood of the tracks fit versus point fit. This has been applied to real data and a preliminary analysis of atmospheric muons with a 5-lines detector is performed. (author)

  7. The atmospheric pollution in a few words; La pollution atmospherique en bref

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This paper takes stock briefly on the different pollution sources (carbon dioxide, nitrogen oxides, sulfur dioxide, VOC, methane...), the mechanisms (acidification, photochemical pollution, eutrophication, greenhouse effect, ozone...) and the effects on the health. (A.L.B.)

  8. Policemen exposure to atmospheric pollutants in Paris; Exposition des policiers aux polluants atmospheriques a Paris

    Energy Technology Data Exchange (ETDEWEB)

    Bugajny, Ch.; Coursimault, A.; Donati, J.; Vieillard, H. [Laboratoire Central de la Prefecture de Police de Paris, 75 (France); Ducos, P.; Gaudin, R. [Institut National de Recherche et de Securite, 54 - Vandoeuvre les Nancy (France)

    2000-07-01

    The objective of this study was to evaluate the effects of automotive pollution on police health in Paris, more particularly those that are working near streets and crossroads; police working indoors are included in measurements as a reference population. This work included individual exposure measurements to some urban pollution main indicators and biological determinations to estimate the impact of these pollutants on health. Biological measurements, including determinations of carboxyhemoglobin, lead in blood and trans, trans-muconic acid in urine were realised. Carbon monoxide and benzene individual exposure had been measured by the use of individual analysers and diffusive samplers respectively. Motorcycle policemen and policemen at crossroads are more exposed than reference population working indoor. CO mean exposure levels are 6, 8 mg/m{sup 3} for motorcycle policemen, 5, 4 mg/m{sup 3} for policemen at crossroads, compared to 3, 6 mg/m{sup 3} for policemen working indoors. Carboxyhemoglobin mean values before work are four to five times more important for smokers (4, 5 % HbCO) than no-smokers (1,0%HbCO). After work, these values are respectively 5,3 % and 1,1 %. Non-smokers agents don't reach the OMS value (2,5%HbCO), even after work. Smoking contributes to higher levels of CO in blood than car exhaust pollutants, even for high air pollutants concentrations. Lead blond levels, which average is 45{mu}g/l, are clearly smaller than the OMS value (200{mu}g/l). About non-smokers agents, benzene median exposures are 74 {mu}g/m{sup 3} for motorcycle policemen, 19 {mu}g/m{sup 3} for policemen at crossroads, compared to 8 {mu}g/m{sup 3} for sedentary agents. If motorcycle agents filled up the tank with gasoline, benzene median exposure level is 229 {mu}g/m{sup 3}. Differences between smokers and non-smokers benzene exposure are not significant. For non-smokers agents, median trans, trans muconic acid values after work are 0,06 mg/l for pollution exposed agents and 0,05 mg/l for sedentary policemen. There is no significant differences of trans, trans-muconic acid concentrations before and alter work, whatever the work may be. For smokers agents, median trans, trans muconic acid values after work are 0,15 mg/l for pollution exposed agents and 0,11 mg/l for sedentary policemen. Trans, trans-muconic acid most important increase during work is measured for motorcycle agents (0,06 mg/l). Differences of median biological results after work have been measured between no-smokers and smokers policemen (0,06 mg/l for sedentary agents, 0,07 mg/l for policemen at crossroads and 0,10 mg/l for motorcycle agents). Filling up the tank with gasoline has no significant influence on biological results. (authors)

  9. Inventories of atmospheric pollutants emissions in France under the convention framework on the long range transboundary air pollution; Inventaire des emissions de polluants atmospheriques en France au titre de la convention sur la pollution atmospherique tranfrontaliere a longue distance

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-12-01

    The present report supplies emission data, for France, concerning all the substances covered by the different protocols adopted under the Convention on Long Range Transboundary Air Pollution (LRTAP), on behalf of the United Nations Economic Commission for Europe (UNECE). The substances covered are sulphur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}), non methane volatile organic compounds (NMVOCs), ammonia (NH{sub 3}), carbon monoxide (CO), total suspended particles (TSP), fine particles (PM{sub 10} and PM{sub 2,5}), heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, Se, Zn) and persistent organic pollutants (POPs). Data are reported according to new specifications adopted in Autumn 2001 regarding substances and source coverage. Parties to the convention have to report annually emissions of these substances. (author)

  10. Amor celeste e amor terrestre: o encontro de Alcibíades e Sócrates em O banquete, de Platão

    OpenAIRE

    Gutman, Guilherme

    2009-01-01

    Neste texto realiza-se uma introdução à leitura de O banquete, de Platão, em especial de seu último trecho, ao qual corresponde o encontro de Alcibíades e Sócrates. Procurou-se ainda, indicar algumas discussões despertadas por esse diálogo platônico; principalmente aquelas que fazem referência às relações entre a filosofia, a literatura e a psicanálise. En este texto se realiza una introducción a la lectura de El Banquete, de Platón; especialmente del último trecho, que corresponde al encu...

  11. PORTFOLIO - LA AMISTAD CELESTE Exposición Espacio de Creación Contemporánea (ECCO). Cádiz, 14 Octubre 2015 - 10 Enero 2016

    OpenAIRE

    Pérez-Bustamante Mourier, Ana Sofía

    2015-01-01

    Exposición Organiza: Fundación Carlos Edmundo de Ory (Cádiz) Colaboran: Espacio de Creación Contemporánea de Cádiz & Fundación Unicaja & Universidad de Cádiz Comisaria: Ana Sofía Pérez-Bustamante Mourier, Profa Titular de la UCA Director Gerente de Proyectos de la Fundación Carlos Edmundo de Ory: Javier Vela Diseño de mobiliario: Pablo Gallardo Lago Instalación de sonido: Paz Ponce Contenidos -Fondos documentales y bibliográficos de la Fundación Carlos Edmundo de O...

  12. Efectos ambientales por el cambio de uso de suelo en la etapa la arboleda, en la urbanizaciòn ciudad celeste, canton samborondon

    OpenAIRE

    Espol; Jordan Rubio, Joann Eduardo; Piedra Soto, Dimitri

    2017-01-01

    Este trabajo se enfocó en las consecuencias causadas por el cambio de uso de suelo sobre el ambiente, por la actividad del movimiento de tierra que se realiza para el proceso de construcción de viviendas en la etapa “la arboleda” de la urbanización “ciudad celeste” en el cantón samborondón, provincia del guayas. Guayaquil MAGISTER EN CAMBIO CLIMATICO

  13. Contribution to the modeling of atmospheric pollution in cities; Contribution a la modelisation de la pollution atmospherique dans les villes

    Energy Technology Data Exchange (ETDEWEB)

    Glockmer, St.

    2000-07-01

    Pollution generated by urban traffic and by industry at its periphery is a serious problem of our cities. Once emitted in the atmosphere, pollutants undergo two types of constraints: on one side they react chemically one with another and, on the other side, they are transported by the wind. We have chosen to work on the dynamical, thermal and chemical aspects of the pollution at different scales of the phenomena: local scale (around a group of buildings) and meso-scale (a whole city). Our ambition is not to realize a complete model but to advance step by step on each aspect. We have contributed to the realization of a numerical tool that will be completed and used for concrete pollution episodes. The first chapter is a description of the atmospheric boundary layer. Chapters two and three present models and results of numerical simulations. We stress on k-{epsilon}, RNG and v{sup 2}-f turbulence models, radiative heat transfer models and dynamical and thermal wall laws that allow to take in consideration surface roughness. The last chapter is dedicated to atmospheric chemistry. We have moreover developed a general solver of any number of transport equations coupled by a stiff chemistry and simplified ozone kinetics. (author)

  14. Inauguration of the ANDRA atmospheric station in Houdelaincourt; Inauguration de la station atmospherique de l'Andra a Houdelaincourt

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    This document briefly presents the atmospheric monitoring station inaugurated in Houdelaincourt (Meuse) and installed by the ANDRA within the frame of the ICOS (Integrated Carbon Observing System) European infrastructure project which aims at developing air and greenhouse gas monitoring over Europe. It also recalls that this station is part of a set of means of monitoring, experimentation and protection of the environment within the frame of high and medium level nuclear waste storage project in Meuse and Haute-Marne. The document also proposes brief presentations of the different actors involved in the creation of this station: the LSCE (laboratory of sciences of climate and environment), Meteo-France, Air Lorraine, the IRSN, and the LGGE (laboratory of glaciology and geophysics of the environment)

  15. Aviation and the atmospheric environment. Present regulations; L`aviation et l`environnement atmospherique la reglementation actuelle

    Energy Technology Data Exchange (ETDEWEB)

    Dimitrov, Ch [Direction Generale de l` Aviation Civile (France)

    1994-12-31

    The two main environmental impacts of air transport are caused by noise and emissions. The International Civil Aviation Organization (ICAO) decided to address environmental issues in the early seventies and started establishing an action programme regarding the environment. Emissions standards were adopted in 1981 and introduced in ICAO Annex 16 as Volume II. Contracting States are required to include ICAO standards in their national regulations or to notify any differences. VOLUME II contains standards relating to the control of fuel venting, smoke and gaseous emissions (namely hydrocarbons, carbon monoxide and nitrogen oxides) from turbo-jet and turbofan engines intended for subsonic and supersonic propulsion. The stringency of NO{sub x} emissions limits was increased as from 1993. An ICAO Council committee, known as the Committee on Aviation Environmental Protection (CAEP), is in charge of proposing amendments to Annex 16. One of its working groups is assessing the need to modify current Volume II provisions and studying possible evolution of emissions standards. As a result of its work programme, it will submit several proposals for amendments of Annex 16 - Volume II at the next Committee meeting scheduled in late 1995 or early 1996. (author)

  16. Infrared remote sensing of atmospheric aerosols; Apports du sondage infrarouge a l'etude des aerosols atmospheriques

    Energy Technology Data Exchange (ETDEWEB)

    Pierangelo, C.

    2005-09-15

    The 2001 report from the Intergovernmental Panel on Climate Change emphasized the very low level of understanding of atmospheric aerosol effects on climate. These particles originate either from natural sources (dust, volcanic aerosols...) or from anthropogenic sources (sulfates, soot...). They are one of the main sources of uncertainty on climate change, partly because they show a very high spatio-temporal variability. Observation from space, being global and quasi-continuous, is therefore a first importance tool for aerosol studies. Remote sensing in the visible domain has been widely used to obtain a better characterization of these particles and their effect on solar radiation. On the opposite, remote sensing of aerosols in the infrared domain still remains marginal. Yet, not only the knowledge of the effect of aerosols on terrestrial radiation is needed for the evaluation of their total radiative forcing, but also infrared remote sensing provides a way to retrieve other aerosol characteristics (observations are possible at night and day, over land and sea). In this PhD dissertation, we show that aerosol optical depth, altitude and size can be retrieved from infrared sounder observations. We first study the sensitivity of aerosol optical properties to their micro-physical properties, we then develop a radiative transfer code for scattering medium adapted to the very high spectral resolution of the new generation sounder NASA-Aqua/AIRS, and we finally focus on the inverse problem. The applications shown here deal with Pinatubo stratospheric volcanic aerosol, observed with NOAA/HIRS, and with the building of an 8 year climatology of dust over sea and land from this sounder. Finally, from AIRS observations, we retrieve the optical depth at 10 {mu}m, the average altitude and the coarse mode effective radius of mineral dust over sea. (author)

  17. Modelling and numerical simulation of the General Dynamic Equation of aerosols; Modelisation et simulation des aerosols atmospheriques

    Energy Technology Data Exchange (ETDEWEB)

    Debry, E.

    2005-01-15

    Chemical-transport models are now able to describe in a realistic way gaseous pollutants behavior in the atmosphere. Nevertheless atmospheric pollution also exists as fine suspended particles, called aerosols, which interact with gaseous phase, solar radiation, and have their own dynamic behavior. The goal of this thesis is the modelling and numerical simulation of the General Dynamic Equation of aerosols (GDE). Part I deals with some theoretical aspects of aerosol modelling. Part II is dedicated to the building of one size resolved aerosol model (SIREAM). In part III we perform the reduction of this model in order to use it in dispersion models as POLAIR3D. Several modelling issues are still opened: organic aerosol matter, externally mixed aerosols, coupling with turbulent mixing, and nano-particles. (author)

  18. Infrared remote sensing of atmospheric aerosols; Apports du sondage infrarouge a l'etude des aerosols atmospheriques

    Energy Technology Data Exchange (ETDEWEB)

    Pierangelo, C

    2005-09-15

    The 2001 report from the Intergovernmental Panel on Climate Change emphasized the very low level of understanding of atmospheric aerosol effects on climate. These particles originate either from natural sources (dust, volcanic aerosols...) or from anthropogenic sources (sulfates, soot...). They are one of the main sources of uncertainty on climate change, partly because they show a very high spatio-temporal variability. Observation from space, being global and quasi-continuous, is therefore a first importance tool for aerosol studies. Remote sensing in the visible domain has been widely used to obtain a better characterization of these particles and their effect on solar radiation. On the opposite, remote sensing of aerosols in the infrared domain still remains marginal. Yet, not only the knowledge of the effect of aerosols on terrestrial radiation is needed for the evaluation of their total radiative forcing, but also infrared remote sensing provides a way to retrieve other aerosol characteristics (observations are possible at night and day, over land and sea). In this PhD dissertation, we show that aerosol optical depth, altitude and size can be retrieved from infrared sounder observations. We first study the sensitivity of aerosol optical properties to their micro-physical properties, we then develop a radiative transfer code for scattering medium adapted to the very high spectral resolution of the new generation sounder NASA-Aqua/AIRS, and we finally focus on the inverse problem. The applications shown here deal with Pinatubo stratospheric volcanic aerosol, observed with NOAA/HIRS, and with the building of an 8 year climatology of dust over sea and land from this sounder. Finally, from AIRS observations, we retrieve the optical depth at 10 {mu}m, the average altitude and the coarse mode effective radius of mineral dust over sea. (author)

  19. Study of the CP violation in the channel B{sup 0} {yields} J/{psi}K{sub S}{sup 0} and development of an aerogel Cherenkov counter; Etude de la violation de CP dans le canal B{sup 0} {yields} J/{psi}K{sub S}{sup 0} et developpement d`un compteur Tcherenkov a aerogel

    Energy Technology Data Exchange (ETDEWEB)

    Lafaye, Remi [Savoie Univ., 73 - Chambery (France)

    1998-05-11

    CP violation and the mass generation problem, will be the two fundamental points for Particle Physics at the dawn of the third millennium. The BABAR experiment, which is installed at PEP-II SLAC B-factory, aims to study CP violation in the B meson systems. It will be then possible to test the standard model explanation of CP violation and may be to highlight new sources. In order to study CP violation with the BABAR experiment it is mandatory to identify most of the produced particles. The first part of this thesis presents the study we carried out on a project of Cherenkov aerogel threshold counters for separating pions from kaons in the momentum region between 0.5 and 4.3 GeV/c. This study includes: preliminary search on materials (reflecting wrappings, wavelength shifters and aerogel), cells and light guides geometry and prototype simulation. Test beam results have shown the feasibility of such a detector. The second part of this thesis deals with the CP parameter measurement that could be achieved at the BABAR experiment for the B{sup 0} {yields} J/{psi}K{sub S}{sup 0} channel, where the J/{psi} decays in lepton mode. The reconstruction efficiency, background level, tagging efficiency as well as the resolution on the B vertex positions are studied. The measurement of the expected asymmetry is made with a probabilistic method or a fit and the resolution on the parameter sin 2{beta} that could be achieved is estimated. It is then shown that an uncertainty of 0.075 on sin 2{beta} could be reached in 1 year of data taking at the BABAR experiment, corresponding to an integrated luminosity of 30 fbarn{sup -1}. (author) 89 refs., 89 figs., 28 tabs.

  20. Dissolution process of atmospheric aerosol particles into cloud droplets; Processus de dissolution des aerosols atmospheriques au sein des gouttes d'eau nuageuses

    Energy Technology Data Exchange (ETDEWEB)

    Desboeufs, K

    2001-01-15

    Clouds affect both climate via the role they play in the Earth's radiation balance and tropospheric chemistry since they are efficient reaction media for chemical transformation of soluble species. Cloud droplets are formed in the atmosphere by condensation of water vapour onto aerosol particles, the cloud condensation nuclei (CCN). The water soluble fraction of these CCN governs the cloud micro-physics, which is the paramount factor playing on the radiative properties of clouds. Moreover, this soluble fraction is the source of species imply in the oxidation/reduction reactions in the aqueous phase. Thus, it is of particular importance to understand the process controlling the solubilization of aerosols in the cloud droplets. The main purpose of this work is to investigate experimentally and theoretically the dissolution of particles incorporated in the aqueous phase. From the studies conducted up to now, we have identify several factors playing on the dissolution reaction of aerosols. However, the quantification of the effects of these factors is difficult since the current means of study are not adapted to the complexity of cloud systems. First, this work consisted to perform a experimental system, compound by an open flow reactor, enabling to follow the kinetic of dissolution in conditions representative of cloud. This experimental device is used to a systematic characterisation of the known factors playing on the dissolution, i.e. pH, aerosol nature, aerosol weathering... and also for the identification and the quantification of the effects of other factors: ionic strength, acid nature, clouds processes. These experiments gave quantitative results, which are used to elaborate a simple model of aerosol dissolution in the aqueous phase. This model considers the main factors playing on the dissolution and results in a general mechanism of aerosol dissolution extrapolated to the cloud droplets. (author)

  1. Caracterisation, modelisation et validation du transfert radiatif d'atmospheres non standard; impact sur les corrections atmospheriques d'images de teledetection

    Science.gov (United States)

    Zidane, Shems

    This study is based on data acquired with an airborne multi-altitude sensor on July 2004 during a nonstandard atmospheric event in the region of Saint-Jean-sur-Richelieu, Quebec. By non-standard atmospheric event we mean an aerosol atmosphere that does not obey the typical monotonic, scale height variation employed in virtually all atmospheric correction codes. The surfaces imaged during this field campaign included a diverse variety of targets : agricultural land, water bodies, urban areas and forests. The multi-altitude approach employed in this campaign allowed us to better understand the altitude dependent influence of the atmosphere over the array of ground targets and thus to better characterize the perturbation induced by a non-standard (smoke) plume. The transformation of the apparent radiance at 3 different altitudes into apparent reflectance and the insertion of the plume optics into an atmospheric correction model permitted an atmospheric correction of the apparent reflectance at the two higher altitudes. The results showed consistency with the apparent validation reflectances derived from the lowest altitude radiances. This approach effectively confirmed the accuracy of our non-standard atmospheric correction approach. This test was particularly relevant at the highest altitude of 3.17 km : the apparent reflectances at this altitude were above most of the plume and therefore represented a good test of our ability to adequately correct for the influence of the perturbation. Standard atmospheric disturbances are obviously taken into account in most atmospheric correction models, but these are based on monotonically decreasing aerosol variations with increasing altitude. When the atmospheric radiation is affected by a plume or a local, non-standard pollution event, one must adapt the existing models to the radiative transfer constraints of the local perturbation and to the reality of the measurable parameters available for ingestion into the model. The main inputs of this study were those normally used in an atmospheric correction : apparent at-sensor radiance and the aerosol optical depth (AOD) acquired using ground-based sunphotometry. The procedure we employed made use of a standard atmospheric correction code (CAM5S, for Canadian Modified 5S, which comes from the 5S radiative transfer model in the visible and near infrared) : however, we also used other parameters and data to adapt and correctly model the special atmospheric situation which affected the multi-altitude images acquired during the St. Jean field campaign. We then developed a modeling protocol for these atmospheric perturbations where auxiliary data was employed to complement our main data-set. This allowed for the development of a robust and simple methodology adapted to this atmospheric situation. The auxiliary data, i.e. meteorological data, LIDAR profiles, various satellite images and sun photometer retrievals of the scattering phase function, were sufficient to accurately model the observed plume in terms of a unusual, vertical distribution. This distribution was transformed into an aerosol optical depth profile that replaced the standard aerosol optical depth profile employed in the CAM5S atmospheric correction model. Based on this model, a comparison between the apparent ground reflectances obtained after atmospheric corrections and validation values of R*(0) obtained from the lowest altitude data showed that the error between the two was less than 0.01 rms. This correction was shown to be a significantly better estimation of the surface reflectance than that obtained using the atmospheric correction model. Significant differences were nevertheless observed in the non-standard solution : these were mainly caused by the difficulties brought about by the acquisition conditions, significant disparities attributable to inconsistencies in the co-sampling / co-registration of different targets from three different altitudes, and possibly modeling errors and / or calibration. There is accordingly room for improvement in our approach to dealing with such conditions. The modeling and forecasting of such a disturbance is explicitly described in this document: our goal in so doing is to permit the establishment of a better protocol for the acquisition of more suitable supporting data. The originality of this study stems from a new approach for incorporating a plume structure into an operational atmospheric correction model and then demonstrating that the approach was a significant improvement over an approach that ignored the perturbations in the vertical profile while employing the correct overall AOD. The profile model we employed was simple and robust but captured sufficient plume detail to achieve significant improvements in atmospheric correction accuracy. The overall process of addressing all the problems encountered in the analysis of our aerosol perturbation helped us to build an appropriate methodology for characterizing such events based on data availability, distributed freely and accessible to the scientific community. This makes our study adaptable and exportable to other types of non-standard atmospheric events. Keywords : non-standard atmospheric perturbation, multi-altitude apparent radiances, smoke plume, Gaussian plume modelization, radiance fit, AOD, CASI

  2. Dissolution process of atmospheric aerosol particles into cloud droplets; Processus de dissolution des aerosols atmospheriques au sein des gouttes d'eau nuageuses

    Energy Technology Data Exchange (ETDEWEB)

    Desboeufs, K.

    2001-01-15

    Clouds affect both climate via the role they play in the Earth's radiation balance and tropospheric chemistry since they are efficient reaction media for chemical transformation of soluble species. Cloud droplets are formed in the atmosphere by condensation of water vapour onto aerosol particles, the cloud condensation nuclei (CCN). The water soluble fraction of these CCN governs the cloud micro-physics, which is the paramount factor playing on the radiative properties of clouds. Moreover, this soluble fraction is the source of species imply in the oxidation/reduction reactions in the aqueous phase. Thus, it is of particular importance to understand the process controlling the solubilization of aerosols in the cloud droplets. The main purpose of this work is to investigate experimentally and theoretically the dissolution of particles incorporated in the aqueous phase. From the studies conducted up to now, we have identify several factors playing on the dissolution reaction of aerosols. However, the quantification of the effects of these factors is difficult since the current means of study are not adapted to the complexity of cloud systems. First, this work consisted to perform a experimental system, compound by an open flow reactor, enabling to follow the kinetic of dissolution in conditions representative of cloud. This experimental device is used to a systematic characterisation of the known factors playing on the dissolution, i.e. pH, aerosol nature, aerosol weathering... and also for the identification and the quantification of the effects of other factors: ionic strength, acid nature, clouds processes. These experiments gave quantitative results, which are used to elaborate a simple model of aerosol dissolution in the aqueous phase. This model considers the main factors playing on the dissolution and results in a general mechanism of aerosol dissolution extrapolated to the cloud droplets. (author)

  3. Development of multivariate and multi-sensors systems for the measurement of atmospheric pollutants; Developpement de systemes multicapteurs et multivariables pour la mesure en continu de polluants atmospheriques

    Energy Technology Data Exchange (ETDEWEB)

    Kamionka, M.

    2005-04-15

    The purpose of this work was to measure the concentrations of atmospheric pollutants using sensors based on a metal semiconductor, tin dioxide. These sensors were tested with two reducing gases which are carbon monoxide (0-20 ppm), a mixture of hydrocarbons (0-10 ppm) and two oxidizing gases which is ozone (0-500 ppb) and nitrogen dioxide (0-500 ppb). One of the major disadvantages of this type of sensor is their lack of selectivity. Thus the association of several different sensors in multi-sensors system can be a solution. We have developed an automated test bench able to generate the suitable gas concentrations with a controlled humidity. It is then possible to carry out the acquisition of four devices (mono or multi-sensors) with cycles of temperature. We followed the evolution with their age of the performances of various sensors worked out by serigraphy. At the end of these experiments, we showed the interest of the use of some of these sensors for the evaluation of two major components of pollution: ozone and hydrocarbons. We could not prove that the capacitive effects and the effects of electrode were useful parameters for our application. Nevertheless, the measurement with increasing temperature give additional information. Thus, two multi-sensors systems were carried out. One associates three independent sensors and the other consists of three layers deposited on the same heating substrate. These three layers are initially identical (tin dioxide) but two are covered with a thin film, platinum for one and silica for the other. Moreover, one system made up of three commercial sensors used with a constant temperature was also tested. For each studied system, we built behavior models using a Neural Network algorithm. Whereas the models carried out using synthetic gas mixtures appeared unusable for measurements in real pollution, it was shown that a model calibrated directly with air bled in urban environment appears effective for the measurement of hydrocarbon and the ozone concentrations. The portability of these models between various identical multi-sensors was proven, but their lifespan was limited to ten days. (author)

  4. Vocabulary of acid precipitation and air pollution. Terminology bulletin 175. Vocabulaire des precipitations acides et de la pollution atmospherique. Bulletin de terminologie 175

    Energy Technology Data Exchange (ETDEWEB)

    Rivard, D

    1988-01-01

    This English-French vocabulary includes about 600 concepts on acid rain as well as general air pollution terminology. A large number of official names and their abbreviations have also been incorporated into the dictionary. The vocabulary is arranged alphabeticaly into a series of terminology files, each of which begins with a main entry in English and French. The main entry represents those terms selected as being of superior terminological quality. The main entry may be followed by sub-entries, which are synonyms, and may also be followed by a definition, an example of usage, a defining context, or a terminological observation. Sub-entries are in the same alphabetical sequence as the main entries, and refer the reader to the main entry. An index of French terms is also included. 243 refs.

  5. Detection of atmospheric tritium by scintillation. Variations in its concentration in France; Detection du tritium atmospherique par scintillation. Evolution de sa concentration en France

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-06-01

    The tritium released into the atmosphere as a result of the explosion of thermonuclear devices is a useful radioactive tracer for the study of certain geophysical problems. The low concentrations found however call for the use of extremely sensitive detectors. Two detection methods using liquid scintillators are described. In the first method, the sample is introduced into the scintillator in liquid form, after prior concentration of the tritium by electrolysis. In the second method the tritium is incorporated into the scintillator solvent molecule by chemical synthesis. In the last part of the report are examined the variations in the tritium concentration in rain-water and of the free hydrogen in the air in France. A discussion is then made of the seasonal variations in the case of rain-water and these are compared to the variations in the strontium-90 concentrations. (author) [French] Le tritium introduit dans l'atmosphere par les explosions d'armes thermonucleaires est un traceur radioactif Interessant pour l'etude de certains problemes de geophysique. Les faibles concentrations rencontrees obligent toutefois a utiliser des detecteurs extremement sensibles. On decrit deux methodes de detection utilisant des scintillateurs liquides. Dans la premiere methode, l'echantillon est introduit dans le scintillateur, sous forme aqueuse, apres une concentration prealable du tritium par electrolyse. Dans la seconde methode, le tritium est incorpore a la molecule du solvant du scintillateur par synthese chimique. Dans la derniere partie du rapport, on examine l'evolution de la concentration du tritium dans les eaux de precipitation et l'hydrogene libre de l'air en France. On discute ensuite les variations saisonnieres dans le cas des eaux de precipitation et on les compare aux variations du strontium 90. (auteur)

  6. Modeling of atmospheric pollution at the regional scale: application to the Esquif campaign; Modelisation a l'echelle regionale de la pollution atmospherique: application a la campagne Esquif

    Energy Technology Data Exchange (ETDEWEB)

    Sarrat, C

    2003-06-01

    The Esquif experimental campaign (study and simulation of air quality in Ile-de-France (Paris region, France)) took place between 1998 and 2000 with the aim of better understanding the dynamical and chemical processes leading to atmospheric pollution peaks in Paris. The construction of a rich and diversified database (12 periods of intensive monitoring (PIM)) has been implemented with the aim of improving the existing chemical-transport models in general and air quality forecasting models in particular. In the framework of this study, the data collected during PIM 2 and 6 were used for the validation and analysis of situations of intensive pollution, simulated with the meso-scale numerical meteorological and chemical model Meso-NHC. The validation of both the dynamic fields (temperature and potential temperature, wind, height of the boundary layer) and the chemical fields (mainly O{sub 3}, NO{sub x}, NO{sub y}, PAN, isoprene) of the model allows to discuss some of the parameters of the model such as the initialization, the boundary forcing and the resolution. Then, a study of the dynamical processes allows to analyze the formation and reinforcement of the pollution conditions. Stress is put on the interaction of the regional scale processes with the photochemical pollution events. In this framework, the dynamical-chemical interaction processes are analyzed in detail, in particular when pollution levels are reinforced by the intrusion of residual ozone inside the convective boundary layer, dragged by the turbulence. Also, the impact of the urban hot island and of the urban wind on the redistribution of primary and secondary pollutants are considered. An analysis of the impact of hydrocarbons of biogenic origin on the ozone concentrations with respect to the temperature and to the presence of primary compounds has been performed for the PIM 2 and 6 of the Esquif campaign. (J.S.)

  7. Modelling atmospheric circulations for the study of Alpine valleys pollution; Modelisation des circulations atmospheriques pour l'etude de la pollution des vallees alpines

    Energy Technology Data Exchange (ETDEWEB)

    Brulfert, G

    2004-11-15

    Local weather phenomena observed in alpine valleys frequently lead to the accumulation of emitted anthropogenic airborne species in the low layers of the atmosphere. The development of a numerical model allows reproducing the chemical evolution of air mass during POVA intensive period of observations. In Chamonix and Maurienne valley, computations of photochemical indicators (NO{sub y}, O{sub 3}/NO{sub z}, H{sub 2}O{sub 2}/HNO{sub 3}) prove the ozone regime to be control by volatile organic compounds. Moreover simulation highlighted that the major part of this secondary pollutant is regionally produced. The development of an indicator who localised ozone production sites can help to define abatement scenarios. The chemical mechanism RACM allows describing the evolution of many species. It is possible to conclude that in winter road traffic and heating are the main sources of volatile organic compounds. (author)

  8. Greenhouse gases regional fluxes estimated from atmospheric measurements; Estimation des flux de gaz a effet de serre a l'echelle regionale a partir de mesures atmospheriques

    Energy Technology Data Exchange (ETDEWEB)

    Messager, C

    2007-07-15

    build up a new system to measure continuously CO{sub 2} (or CO), CH{sub 4}, N{sub 2}O and SF{sub 6} mixing ratios. It is based on a commercial gas chromatograph (Agilent 6890N) which have been modified to reach better precision. Reproducibility computed with a target gas on a 24 hours time step gives: 0.06 ppm for CO{sub 2}, 1.4 ppb for CO, 0.7 ppb for CH{sub 4}, 0.2 ppb for N{sub 2}O and 0.05 ppt for SF{sub 6}. The instrument's run is fully automated, an air sample analysis takes about 5 minutes. In July 2006, I install instrumentation on a telecommunication tall tower (200 m) situated near Orleans forest in Trainou, to monitor continuously greenhouse gases (CO{sub 2}, CH{sub 4}, N{sub 2}O, SF{sub 6}), atmospheric tracers (CO, Radon-222) and meteorological parameters. Intake lines were installed at 3 levels (50, 100 and 180 m) and allow us to sample air masses along the vertical. Continuous measurement started in January 2007. I used Mace Head (Ireland) and Gif-sur-Yvette continuous measurements to estimate major greenhouse gases emission fluxes at regional scale. To make the link between atmospheric measurements and surface fluxes, we need to quantify dilution due to atmospheric transport. I used Radon-222 as tracer (radon tracer method) and planetary boundary layer heights estimates from ECMWF model (boundary layer budget method) to parameterize atmospheric transport. In both cases I compared results to available emission inventories. (author)

  9. Effects of atmospheric neutrons on advanced micro-electronic devices, standards and applications; Effets des neutrons atmospheriques sur les dispositifs microelectroniques avances, normes et applications

    Energy Technology Data Exchange (ETDEWEB)

    Leray, J.L. [CEA, 75 - Paris (France); Baggio, J.; Ferlet-Cavrois, V.; Flament, O. [CEA Bruyeres-le-Chatel, 91 (France)

    2005-10-01

    Since the 1980's, it is known that terrestrial cosmic rays, mainly reported as atmospheric neutrons, can penetrate the natural shielding of buildings, equipments and circuit package and induce soft errors in integrated circuits and breakdown of power devices. The high-energy neutron fluxes of interest, larger than 10 MeV, range between 10 particles/cm{sup 2}/hour at sea level and 10{sup 4} particles/cm{sup 2}/hour at typical airplanes flight altitude of 30000 feet, with modulation due to solar flares. In the 1990's, the phenomenon has pervaded as a consequence of the road-map of electronic devices especially the down-scaling of transistor dimensions, the increase of signal bandwidth and the increase of the size of DRAM and SRAM memory, stand-alone or embedded on processors and system-on-chips. Failure-in-time and soft error rate became unacceptable. Test standards and design solutions have been proposed to maintain reliability of commercial products and improve those used in special high-reliability equipments such as avionic computers. The paper describes the atmospheric neutron flux, the effects in the main classes of devices and specific cases such as neutron induced single event upset observed in CMOS vs. CMOS/SOI and some mitigation issues. In this paper, a model called CCPM (critical cross-point model) is proposed to provide critical graphs of technology node sensitivity along the scaling trend of CMOS. (authors)

  10. Greenhouse gases regional fluxes estimated from atmospheric measurements; Estimation des flux de gaz a effet de serre a l'echelle regionale a partir de mesures atmospheriques

    Energy Technology Data Exchange (ETDEWEB)

    Messager, C

    2007-07-15

    build up a new system to measure continuously CO{sub 2} (or CO), CH{sub 4}, N{sub 2}O and SF{sub 6} mixing ratios. It is based on a commercial gas chromatograph (Agilent 6890N) which have been modified to reach better precision. Reproducibility computed with a target gas on a 24 hours time step gives: 0.06 ppm for CO{sub 2}, 1.4 ppb for CO, 0.7 ppb for CH{sub 4}, 0.2 ppb for N{sub 2}O and 0.05 ppt for SF{sub 6}. The instrument's run is fully automated, an air sample analysis takes about 5 minutes. In July 2006, I install instrumentation on a telecommunication tall tower (200 m) situated near Orleans forest in Trainou, to monitor continuously greenhouse gases (CO{sub 2}, CH{sub 4}, N{sub 2}O, SF{sub 6}), atmospheric tracers (CO, Radon-222) and meteorological parameters. Intake lines were installed at 3 levels (50, 100 and 180 m) and allow us to sample air masses along the vertical. Continuous measurement started in January 2007. I used Mace Head (Ireland) and Gif-sur-Yvette continuous measurements to estimate major greenhouse gases emission fluxes at regional scale. To make the link between atmospheric measurements and surface fluxes, we need to quantify dilution due to atmospheric transport. I used Radon-222 as tracer (radon tracer method) and planetary boundary layer heights estimates from ECMWF model (boundary layer budget method) to parameterize atmospheric transport. In both cases I compared results to available emission inventories. (author)

  11. Approaches of health risk assessment in air pollution; Les approches de l'evaluation des risques sanitaires lies a la pollution atmospherique

    Energy Technology Data Exchange (ETDEWEB)

    Festy, B. [Paris-5 Univ., 75 (France). Faculte des Sciences Pharmaceutiques et Biologiques de Paris-Luxembourg

    1997-07-01

    The relationships between health and environment are often difficult to establish due to the large number of contaminants and routes of absorption, the low doses involved, the type of effects (acute or chronic), the lack of specificity, the time before the effects are observed and the low individual risks. A great deal of knowledge is required, beginning with the source of emission and ending up with the effect on health, passing by the quality of the environments, the exposure for the individual and the groups and their perception of the phenomena in pedagogical, social and (dis)comfort terms. The North-American approach to assess the risk tries to understand these different problems by means of an approach that is as scientific, coherent and clear as possible: identification of the danger, estimate of its probability, evaluation of the exposure (populations, conditions) and synthetic characterization of the risk. This procedure comes before the difficult management of the risk and is absolutely necessary to determine the reference values and the standards. The chemical aspects of air pollution (A.P.) raise difficult problems in this area. In practice, the assessment of the risk involves environmental and biological phenomena. The environmental approach involves products (ex. fuels), processes and sources of emissions and, above all, the quality of the atmospheric environments ('immissions') due to the characterization and quantification of more or less classic physico-chemical indicators (SO{sub 2}, particles, NO{sub x}, O{sub 3}, metals, hydrocarbons, etc.) measured on the sites (monitoring networks) or in the laboratory, or more rarely, (eco)-toxicological, measured in the laboratory (cell models) or in the field (bio-indicators). The former provide a fairly exact idea of the external collective exposure of populations. The latter provide a more or less global and biological assessment of the quality of the air consisting of (geno)toxic potentialities. Bacteria and plant examples are provided by way of illustration. The biological approach first uses experimental methods with simplifying or complex biological models (from the bio-molecule to the animal or plant organism) providing qualitative and quantitative data (danger, mechanisms, dose effect function), for exact exposure concerning isolated pollutants or simple mixtures. Controlled human exposure is a more adequate way to study the acute effect thresholds and the dose-response relationships with set conditions of exposure. However, this is obviously limited by ethical considerations. The value and limits of these two experimental approaches will be discussed. Finally, the clinico-epidemiological approach provides knowledge of the harm of A.P. This either involves the clinical observation of accidents (professional or other) that generally arise on an individual scale or epidemiology. The latter identifies the risk factors, action thresholds, dose-response functions and the groups at risk. It uses surveys based on individual data (cross-sectional, cohort, case-control studies) or groups (multi-group temporal or mixed 'ecological' studies). The environmental data are generally collective and more rarely personalized. The health data measure the mortality, morbidity or objective effects or levels of health action (consultations, hospitalization, absenteeism, consumption of drugs, etc.). The advantages and limits of the epidemiological approach will be called to mind as well as the important idea of causality. Approaches of this type will be illustrated with nitrogen dioxide and/or ozone. (author)

  12. Is acidification still a major air pollution concern?; L`acidification est-elle encore un probleme majeur de pollution atmospherique?

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    Although other forms of long-range air pollution are gaining attention, acidification remains an important issue in certain parts of Europe as well as in other continents. In spite of the European 88/609 directive limiting acid emissions from large fuel burning plants, a large part of Europe soils receives acid deposits superior to the tolerance threshold, known as critical loads. Thus, the European Union is considering several new measures, such as a more drastic 88/609 directive, the limitation of emissions country by country, the limitation of sulfur content in heavy fuels, etc. Emission inventories, evaluation tools, long range transfrontier pollution models, integrated assessment, etc. are presented, together with the positions of various French governmental departments, public authorities and industries concerning the european strategy against acidification

  13. Considering a point-source in a regional air pollution model; Prise en compte d`une source ponctuelle dans un modele regional de pollution atmospherique

    Energy Technology Data Exchange (ETDEWEB)

    Lipphardt, M.

    1997-06-19

    This thesis deals with the development and validation of a point-source plume model, with the aim to refine the representation of intensive point-source emissions in regional-scale air quality models. The plume is modelled at four levels of increasing complexity, from a modified Gaussian plume model to the Freiberg and Lusis ring model. Plume elevation is determined by Netterville`s plume rise model, using turbulence and atmospheric stability parameters. A model for the effect of a fine-scale turbulence on the mean concentrations in the plume is developed and integrated in the ring model. A comparison between results with and without considering micro-mixing shows the importance of this effect in a chemically reactive plume. The plume model is integrated into the Eulerian transport/chemistry model AIRQUAL, using an interface between Airqual and the sub-model, and interactions between the two scales are described. A simulation of an air pollution episode over Paris is carried out, showing that the utilization of such a sub-scale model improves the accuracy of the air quality model

  14. Mathematical study of chemical kinetics schemes. Application to air pollution models; Etude mathematique de schemas de cinetique chimique. Application a des modeles de pollution atmospherique

    Energy Technology Data Exchange (ETDEWEB)

    Billette, E.

    1997-06-23

    Complex chemical kinetics modelling is relevant in numerous fields related to the petroleum industry, for instance engine combustion, petrochemistry and atmospheric pollution. Many numerical difficulties are encountered in the computation of these models, mainly due to the large size, the non-linearity and the stiffness of the associated ordinary differential systems. We first studied systems that have an asymptotic behaviour which may be derived from an algebraic analysis. Then we reviewed different methods that make possible the reduction of size and stiffness for chemical kinetics-related differential systems, and suggest possible improvements for some of those methods. We also studied their application to atmospheric chemistry models. Finally, we started to extend those reduction methods to partial differential systems that include, in addition to chemical kinetics, other phenomena such as species emission, advection or diffusion. (author) 44 refs.

  15. Detection of atmospheric tritium by scintillation. Variations in its concentration in France; Detection du tritium atmospherique par scintillation. Evolution de sa concentration en France

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-06-01

    The tritium released into the atmosphere as a result of the explosion of thermonuclear devices is a useful radioactive tracer for the study of certain geophysical problems. The low concentrations found however call for the use of extremely sensitive detectors. Two detection methods using liquid scintillators are described. In the first method, the sample is introduced into the scintillator in liquid form, after prior concentration of the tritium by electrolysis. In the second method the tritium is incorporated into the scintillator solvent molecule by chemical synthesis. In the last part of the report are examined the variations in the tritium concentration in rain-water and of the free hydrogen in the air in France. A discussion is then made of the seasonal variations in the case of rain-water and these are compared to the variations in the strontium-90 concentrations. (author) [French] Le tritium introduit dans l'atmosphere par les explosions d'armes thermonucleaires est un traceur radioactif Interessant pour l'etude de certains problemes de geophysique. Les faibles concentrations rencontrees obligent toutefois a utiliser des detecteurs extremement sensibles. On decrit deux methodes de detection utilisant des scintillateurs liquides. Dans la premiere methode, l'echantillon est introduit dans le scintillateur, sous forme aqueuse, apres une concentration prealable du tritium par electrolyse. Dans la seconde methode, le tritium est incorpore a la molecule du solvant du scintillateur par synthese chimique. Dans la derniere partie du rapport, on examine l'evolution de la concentration du tritium dans les eaux de precipitation et l'hydrogene libre de l'air en France. On discute ensuite les variations saisonnieres dans le cas des eaux de precipitation et on les compare aux variations du strontium 90. (auteur)

  16. Assessment of exposure to atmospheric particles: contribution of individual measurements; Evaluation de l'exposition aux particules atmospheriques: apport des mesures individuelles

    Energy Technology Data Exchange (ETDEWEB)

    Mosqueron, L.; Momas, I. [Universite Rene Descartes, Faculte des Sciences Pharmaceutiques et Biologiques, Lab. d' Hygiene et de Sante Publique, 75 - Paris (France); Le Moullec, Y. [Laboratoire d' Hygiene de la Ville de Paris, 75 (France); Momas, I. [Direction de l' Action Sociale, de l' Enfance et de la Sante, Cellule Epidemiologie, 75 - Paris (France)

    2001-02-01

    There are few studies of individual exposure to atmospheric particles, because of the relatively bulky and noisy sampling devices. These personalized measurements, generally associated with micro-environmental measurements, are aimed at studying the distribution of individual exposure and identifying its main determinants. Methods: A synopsis of the methods implemented in such studies (populations studied, measurements strategies, questionnaires on time-activity patterns, residences and work place) was detailed. The major results are presented and discussed from an epidemiological point of view. Results: The individual exposure measured with portable devices generally were generally found to be higher than the estimations made by combining micro-environmental (outdoor and indoor) measurements and data from time-activity diaries. The difference between results of these two approaches, known as 'personal cloud', remains poorly understood. Correlations between individual measurements and outdoor concentrations are weak; nevertheless, day to day variations of these two series of measurements are better related. The main determinants of individual exposure to particles are identified but a quantification of their contribution remains difficult, except for passive smoking. Conclusion: Personal measurements cannot be used to estimate particle exposure in large scale epidemiological studies. This exposure needs to be modeled. (authors)

  17. Peaks of air pollution and public health. The place of epidemiology; Pics de pollution atmospherique et sante publique. La place de l'epidemiologie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The epidemiological surveillance of sanitary effects linked to the air pollution seems to be the best tool to estimate their impact and to keep a close eye on the short term effects of the ambient pollution on the populations health. In any case, the potential sanitary impact of pollution peaks does not conceal the importance of sanitary effects linked to the background pollution. These peaks constitute sanitary alert signals but are not inevitably the predominant risk for public health. A targeting on these peaks can lead to neglect actions of prevention and to induce these policies towards strategies that will not be the most efficient in term of reduction of mortality attributable to air pollution. (N.C.)

  18. Evaluation of sanitary impact of urban air pollution. Methodological guide.; Evaluation de l'impact sanitaire de la pollution atmospherique urbaine. Guide methodologique

    Energy Technology Data Exchange (ETDEWEB)

    Glorennec, Ph.; Nourry, L [Cellule Inter-Regionale d' Epidemiologie (France); Quenel, Ph. [Institut National de Veille Sanitaire, 94 - Saint Maurice (France)] [and others

    1999-07-01

    The institute of sanitary watch has setting up an epidemiological surveillance plan in nine french towns in order to quantify and to keep a close eye to the relations existing between the urban air pollution and the populations health.The method is detailed with its advantages and its limits. (N.C.)

  19. Experimental and theoretical study of the atmospheric boundary layer over the paris area; Etude experimentale et theorique de la couche limite atmospherique en agglomeration parisienne

    Energy Technology Data Exchange (ETDEWEB)

    Menut, L

    1997-12-15

    This thesis studied the urban boundary layer dynamic behaviour over the Paris area by comparing urban (Paris) and suburban (Palaiseau) dynamic data such as lidars, sodars, sonic anemometers. All the data were obtained during the ECLAP experiment, specifically performed to characterize the differences between a city and its near environment. (author)

  20. Origins of atmospheric aerosols. Basic concepts on aerosol main physical properties; L`aerosol atmospherique: ses origines quelques notions sur les principales proprietes physiques des aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Renoux, A. [Paris-12 Univ., 94 - Creteil (France). Laboratoire de Physique des aerosols et de transferts des contaminations

    1996-12-31

    Natural and anthropogenic sources of atmospheric aerosols are reviewed and indications of their concentrations and granulometry are given. Calculation of the lifetime of an atmospheric aerosol of a certain size is presented and the various modes of aerosol granulometry and their relations with photochemical and physico-chemical processes in the atmosphere are discussed. The main physical, electrical and optical properties of aerosols are also presented: diffusion coefficient, dynamic mobility and relaxation time, Stokes number, limit rate of fall, electrical mobility, optical diffraction

  1. Atmospheric greenhouse effect: more subtle than it looks like; L'effet de serre atmospherique: plus subtil qu'on ne le croit

    Energy Technology Data Exchange (ETDEWEB)

    Dufresne, J.L. [Laboratoire de Meteorologie Dynamique (LMD), Institut Pierre-Simon Laplace (IPSL), CNRS, Universite Pierre et Marie Curie, 75 - Paris (France); Treiner, J. [Paris-6, UPMC et Espace des sciences Pierre-Gilles de Gennes, 75 - Paris (France)

    2011-02-15

    State-of-the-art radiative models can be used to calculate in a rigorous and accurate manner the atmospheric greenhouse effect, as well as its variation with concentration in water vapour or carbon dioxide. A simple explanation of this effect uses an analogy with the greenhouse effect produced by a glass window. While this analogy has pedagogical virtues and provides a first order explanation of the mean temperature of the Earth, it has an important drawback; it is not able to explain why the greenhouse effect increases with increasing carbon dioxide concentration. Indeed, absorption of infrared radiation by carbon dioxide is, under this scheme, almost at its maximum and depends very weakly on CO{sub 2} concentration. It is said to be saturated. In this paper, we explore this question and propose an alternative model which, while remaining simple, correctly takes into account the various mechanisms and provides an understanding of the increasing greenhouse effect with CO{sub 2} concentration, together with the corresponding climate warming. The role of the atmospheric temperature gradient is particularly stressed. (authors)

  2. Inventory of atmospheric pollutants emissions in France - sectorial series and extensive analysis; Inventaire des emissions de polluants atmospheriques en France - serie sectorielles et analyses etendues

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-02-01

    The present report supplies an update of emissions into the atmosphere within the french metropolitan area in the frame of the CORALIE programme according to the 'SECTEN' format defined by CITEPA which raises to report emissions relating to usual economic entities such as industry residential/tertiary, agriculture, etc. Basically, results deal systematically with the period 1990 - 2001, but cover also more extended ranges of time, especially from 1980 for some substances to be considered in the frame of the protocols under the convention on the long range transboundary air pollution and from 1960 for some other substances traditionally inventoried by CITEPA for a long time. Data are presented for 28 different substances and various indicators such as those related to acidification or greenhouse effect. It is observed for most of substances that emissions have been drastically reduced over the ten or twenty last years. More especially for the period 1990 - 2000: The results are presented at the national level for each of the main sectors defined in the SECTEN format. A more detailed breakdown of each main sector is provided for 2000. Results are also given relating to different energy products and several analysis present additional highlights for NMVOCs, HFCs, PFCs and particular sources such as transports. The report contains indications regarding the targets committed by France in the frame of international conventions and directives from the European Union directives. These indications demonstrate that emission trends observed are generally encouraging. The table below summarizes total emissions over the period 1990 - 2001 for all substances mentioned above as well as indicators relating to the acidification and to the greenhouse effect. (author)

  3. The 1979 convention on long range transfrontier air pollution; La convention sur la pollution atmospherique transfrontiere a longue distance de 1979

    Energy Technology Data Exchange (ETDEWEB)

    Jagusiewicz, A. [UNECE, Palais des Nations, Geneve (Switzerland)

    1997-12-31

    Applied in March 1983, the 1979 international Convention have induced five protocols related to sulfur, nitrogen oxide and VOC emissions. After 1994, three new protocols are under study, concerning the reduction of nitrogenous and related compounds, heavy metals and long-lasting organic pollutants. Works and organization of the European EMEP program for the continuous monitoring and evaluation of the long range air pollution transport in Europe, are presented

  4. Is acidification still a major air pollution concern?; L`acidification est-elle encore un probleme majeur de pollution atmospherique

    Energy Technology Data Exchange (ETDEWEB)

    Le Bellac, C. [INES, 75 - Paris (France)

    1997-12-31

    The issue of acid emissions from district space heating systems, which burn heavy fuels and coal, is discussed: it is shown that nitrogen oxide emissions are relatively low; for sulfur dioxide, three solutions are possible: switching to natural gas, but peak periods would require stored fuels; reducing the sulfur content in fuels, but its prices are too erratic; and de-sulfurizing the combustion smokes, but it does not appears as economically sustainable, as the prices for quality fuels and difficult fuels are close and low. It is reminded that district space heating is more especially aimed at council buildings

  5. Modelling atmospheric circulations for the study of Alpine valleys pollution; Modelisation des circulations atmospheriques pour l'etude de la pollution des vallees alpines

    Energy Technology Data Exchange (ETDEWEB)

    Brulfert, G.

    2004-11-15

    Local weather phenomena observed in alpine valleys frequently lead to the accumulation of emitted anthropogenic airborne species in the low layers of the atmosphere. The development of a numerical model allows reproducing the chemical evolution of air mass during POVA intensive period of observations. In Chamonix and Maurienne valley, computations of photochemical indicators (NO{sub y}, O{sub 3}/NO{sub z}, H{sub 2}O{sub 2}/HNO{sub 3}) prove the ozone regime to be control by volatile organic compounds. Moreover simulation highlighted that the major part of this secondary pollutant is regionally produced. The development of an indicator who localised ozone production sites can help to define abatement scenarios. The chemical mechanism RACM allows describing the evolution of many species. It is possible to conclude that in winter road traffic and heating are the main sources of volatile organic compounds. (author)

  6. Modeling of the air pollution on various scales; Modelisation de la pollution atmospherique a differentes echelles. confrontations simulations/mesures pour la preparation d'Escompte 2001

    Energy Technology Data Exchange (ETDEWEB)

    Meleux, F.

    2002-11-15

    On June and July 2001, the campaign ESCOMPTE took place in the Marseille area in southern of France, with the aim of generating a detailed 3-D data base for the study of dynamics and chemistry of high pollution events so as to validate and improve air quality models. Previous to this field experiment, a pre-modelling exercise has been performed to document the dynamic interactions between sea and land breezes and orographic flows over this complex topographical area. This study was carried out using a nesting procedure at local and regional scales using the MESO-NH model (jointly developed by Laboratoire d'Aerologie and Meteofrance at Toulouse). Tracers emitted at various locations in the Marseille and Etang de Berre areas were first followed, then in a second step, full chemistry simulations have been run for two selected periods on June and July 1999, quite similar to the meteorological situations met during the IOP2a and the IOP4 in the 2001 campaign. The performance of the model has been assessed by comparing measured data with simulated data for meteorological parameters and ozone. The general ability of the model to correctly simulate these two situations allows to further study ozone plume developments. In particular, these studies bear upon the relative roles of O{sub 3} transport versus O{sub 3} chemical production, as a function of distance within the plume to anthropogenic emissions and biogenic emissions, together with ozone daily variations and peak values observed at rural sites. After that, ozone chemical production sensitivity is analysed in regards to its precursors. (author)

  7. Air pollution emission reduction techniques in combustion plants; Technique de reduction des emissions de polluants atmospheriques dans les installations de combustion

    Energy Technology Data Exchange (ETDEWEB)

    Bouscaren, R. [CITEPA, Centre Interprofessionnel Technique d`Etudes de la Pollution Atmospherique, 75 - Paris (France)

    1996-12-31

    Separating techniques offer a large choice between various procedures for air pollution reduction in combustion plants: mechanical, electrical, filtering, hydraulic, chemical, physical, catalytic, thermal and biological processes. Many environment-friendly equipment use such separating techniques, particularly for dust cleaning and fume desulfurizing and more recently for the abatement of volatile organic pollutants or dioxins and furans. These processes are briefly described

  8. Source, flux and balance of atmospheric deposition of metals at Ile-de-France; Source, flux et bilan des retombees atmospheriques de metaux en Ile de France

    Energy Technology Data Exchange (ETDEWEB)

    Azimi, S

    2004-07-15

    The urban atmosphere is submitted to large inputs of anthropogenic contaminants arising from both stationary (power plants, industries, etc.) and mobile (road traffic) sources. These small particles may be transported over long distances and affect ecosystems. Significant dry and wet atmospheric deposition also occurs locally and contributes to the contamination of urban runoff. The aim of this study is to compare heavy metal and hydrocarbon atmospheric deposition fluxes to other input ways on agricultural and urban areas to assess their importance. Moreover, a source investigation has been done to identify the main origins of these pollutants. Before the quantification of pollutant fluxes, a comparison of several sampling procedures was performed. As a result, the sampling of total atmospheric deposition is not affected by the funnel material (Teflon and polyethylene) or by the sampling duration (7 and 28 days). However, the rinsing step of the funnel walls showed a higher relative importance during short sampling periods. The relative amount contained in these solutions reached 24 to 40 % of the total flux during weekly sampling periods and 8 to 18 % during monthly sampling periods, whatever the element considered. The temporal evolution of atmospheric deposition showed no seasonal influence on flux variations during the 2001-2002 period. Considering an 8-year period behaviour, between 1994 and 2002, a significant decrease of the deposition fluxes of Cd, Cu, Pb and Zn occurred at the Creteil site which is placed in an industrialized area of the Paris suburb. The decreasing factor reached 16, 2.5, 4 and 7.5 for these elements respectively. At the Ile-de-France scale, the deposition flux levels on urban and semi-urban areas were of the same order of magnitude (?20 tonnes per year for Ba, Cu, Pb and Sr). Since semi-urban surface area is four times higher than urban ones, the important influence of anthropogenic activities on atmospheric deposition of urban areas is evidenced. At the Seine River catchment scale, the atmospheric deposition levels were of the same order of magnitude as Seine River particle contents measured at the catchment estuary (Poses). The flux ratio between atmospheric inputs and Seine particles ranged between 0.8 and 4.8 for Al, Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn. The importance of atmospheric deposition of metals was estimated on agricultural and urban areas. In the first case, the atmospheric fallout appears as the main input way of Cu, Ni and Pb to agro-systems while Cd is mainly introduced by fertilizers. These two input ways induced an increase of Cd, Ni and Pb in the cultivated horizon with an annual balance reaching 0.33, 0.014 and 0.014 %, respectively, of actual stocks while the Cu showed a decrease with an annual balance reaching 0.024 %. In the second case, atmospheric deposition was compared to roof and street runoff. The atmospheric deposition is the main introducing way of most of considered elements, compared to roof runoff excepting Cu, Pb, Ti and Zn which are mainly emitted by the latter. Nevertheless, compared to street runoff, atmospheric deposition levels are 1.5 to 27 times lower than street cleaning ones showing that atmospheric introducing way is not the main introducing way of metals in urban areas. The source investigation on atmospheric deposition was performed using several tools developed during this study. The results allow the characterisation of the anthropogenic sources considered using specific elements or ratios. These tools were applied to the atmospheric deposition data but they did not allowed the determination of anthropogenic activities because of the atmospheric mixture. (author)

  9. Effects of urban air pollution on the inflammatory reaction: involvement of the chemokine pathways; Impact de la pollution atmospherique urbaine sur la reponse inflammatoire: implication des chimiokines

    Energy Technology Data Exchange (ETDEWEB)

    Fahy, O.

    2000-12-01

    Urban air pollution is both gaseous and particulate, and diesel exhausts are now the main source of particles. Diesel particles consist of a carbon core with multiple adsorbed organic compounds, among witch poly-aromatic hydrocarbons. These diesel particles and associated poly-aromatic hydrocarbons are likely to play a role in the recent increase in allergic diseases. In this study, we evaluated the effects of diesel organic extracts on the initiation and the orientation of the allergen-dependent inflammatory reaction by analyzing the dis-regulation of a family of mediators involved in cellular recruitment: the chemokines. We demonstrated that mononuclear cells and alveolar macrophages from normal subjects displayed a dis-regulation in pro-inflammatory chemokine expression and production (IL-8, MCP-1, RANTES) when exposed to diesel organic extracts. In addition we observed a synergy between the effects of diesel and allergen when cells from allergic patients were exposed to both simultaneously, leading to a strong over-production of chemokines, and to the increased capacity of recruiting effector cells such as neutrophils and eosinophils. The MAP kinase pathways seemed largely involved in the transduction of diesel and allergen stimulus, since a specific inhibition almost abolished the dis-regulation of chemokine production. Diesel and allergen also appeared to favour the establishment of a type 2 immune response (pro-allergenic), by preferentially recruiting Th2 lymphocytes via the dis-regulation of chemokine expression (MDC and IP-10). Finally, the humanized SCID mouse model grafted with autologous human skin allowed the in vivo evaluation of a local over-production of chemokine, by analyzing the cellular recruitment in the skin after intra-dermal injection of recombinant chemokines. This model appears useful for the study of the mechanisms of cellular recruitment by chemokines and the potential therapeutic approaches. In conclusion, our study underlines the deleterious effects of a combined exposure to diesel and allergen on an essential parameter of the inflammatory reaction potentially responsible for the recruitment and activation of an increased number of immune cells, and thus the aggravation of allergic patient symptoms. (author)

  10. Una propuesta didáctica orientada a facilitar el aprendizaje y comprensión de los circuitos eléctricos en serie, paralelos y mixtos, usando como pretexto las constelaciones celestes

    OpenAIRE

    Flórez Bohórquez, Ángela Liliana

    2013-01-01

    Aunque el tema “circuitos eléctricos” genera una amplia expectativa entre la mayoría de los estudiantes, debido en su mayor parte a las aplicaciones directas que tienen los circuitos eléctricos sobre el funcionamiento de aparatos electrónicos y tecnología en general, la motivación casi innata se evapora en el ambiente rápidamente, al momento de iniciar la exposición de los conceptos del tema. Esto puede ser producto de variables como la falta de bases conceptuales y herramie...

  11. Anxious bliss: a case study of dissociation in a Mexican nun.

    Science.gov (United States)

    Lester, Rebecca J

    2008-03-01

    This is a case study of Celeste, postulant in a Roman Catholic convent in Mexico who experienced frequent episodes of leaving her body to commune with God. During these experiences, Celeste felt immersed in an ;incredibly beautiful profound silence' where ;time and space were broken.' But as much as Celeste craved these experiences, they also alarmed her; she was acutely aware that they might be indicative of psychological or neurological dysfunction. This article chronicles Celeste's struggles to make sense of her experiences in light of competing explanatory models. Her ultimate resolution suggests intriguing new directions for transcultural psychiatric research.

  12. Atmospheric sulfur and climate changes: a modelling study at mid and high-southern latitudes; Soufre atmospherique et changements climatiques: une etude de modelisation pour les moyennes et hautes latitudes Sud

    Energy Technology Data Exchange (ETDEWEB)

    Castebrunet, H

    2007-09-15

    The mid and high-southern latitudes are still marginally affected by anthropogenic sulfur emissions. They are the only regions in the world where the natural cycle of the atmospheric sulfur may still be observed. Sulfur aerosols are well-known for their radiative impact, and thus interact with climate. Climate can in turn affect atmospheric sulfur sources, distribution and chemistry. Antarctic ice cores provide information on the evolution of climate and sulfur deposition at the surface of the ice sheet at glacial-interglacial time scales. The aim of this thesis is to develop and use modeling towards a better understanding of the atmospheric sulfur cycle in antarctic and sub-antarctic regions. Ice core data are used to validate model results under glacial climate conditions. An Atmospheric General Circulation Model (AGCM) coupled to a sulfur chemistry module is used: the LMD-ZTSulfur model, version 4. An update of both the physical and chemical parts of the model. The model was first performed. The impact of there changes on modelled sulfur cycle are evaluated for modern climate. Further, boundary conditions are adapted to simulate the atmospheric circulation and sulfur cycle at the Last Glacial Maximum, approximately 20,000 years ago. In the model, sulfur is found to be highly sensitive to antarctic sea-ice coverage, which is still poorly known during the ice age. An original dataset of ice-age sea-ice coverage was developed. Its impact on the oceanic emissions of dimethyl sulfide, main precursor of sulfur aerosols at high-southern latitudes, is discussed. Using the same oceanic sulfur reservoirs as for present day climate, the model broadly reproduces the glacial deposits of sulfur aerosols on the Antarctic plateau, suggesting little impact of climate on oceanic sulfur production in the Antarctic region. Sensitivity tests were carried out to draw an up-to-date status of major uncertainties and difficulties facing future progress in understanding atmospheric sulfur and climate. (author)

  13. Evaluation of sanitary impact of urban air pollution. Agglomeration of Bordeaux impact at short and long term; Evaluation de l'impact sanitaire de la pollution atmospherique urbaine. Agglomeration de Bordeaux impact a cour et long terme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-06-15

    A health impact assessment of air pollution based on the I.n.V.S. guidelines has been conducted in Bordeaux area. Atmospheric pollution indicators analyzed were ozone, nitrogen dioxide and particles having diameter below 10 {mu}m. Short term impact of atmospheric pollution has been estimated in term of mortality (total, cardiovascular and respiratory mortality) and hospital admissions (for respiratory, cardiovascular and cardiac reasons) attributable to air pollution. Long-term impact was also assessed by the number of deaths due to atmospheric pollution. The study has been carried out in 22 cities homogeneously exposed belonging to Bordeaux agglomeration, representing a study population of 604,238 inhabitants. In 2001, the atmospheric pollution has directly been responsible in the studied area of 56 anticipated deaths, including half for cardiovascular reasons and 7 for respiratory reasons. Regarding morbidity, 29 hospital admissions for respiratory disease were attributable to air pollution in 2002, including two-thirds among elderly people (aged 65 years and over). Further more, 81 hospitalizations for cardiovascular diseases that occurred in 2002 were attributable to air pollution, including 27 for cardiac reasons. A decrease by 25% of the pollutants could have allowed avoiding about half of the premature deaths and hospital intakes attributable to air pollution. Concerning long term effects, about 200 annual deaths are attributable to chronic exposure to air pollution, and a decrease by 5{mu}g/m{sup 3} of the annual mean of PM{sub 10} could allow avoiding half of these deaths. The results have to be interpreted with care because of the limits of the H.I.A. method. However, they show that air pollution has a non negligible impact even in a city like Bordeaux where target values are mostly respected. They also show that reducing air pollution can have a significant impact in term of mortality and morbidity. However, a policy of atmospheric pollution reduction only based on not exceeding the standard levels would not have the expected benefits on the public health point of view, and to decrease at the source the every day pollutants emission would be more efficient. (author)

  14. Study and management of atmospheric exhaust gas in acetic acid fermentation developing a new process for alcohol vinegar production; Etude et maitrise des rejets atmospheriques en vinaigrerie, developpement d'un procede nouveau de conduite de la fermentation acetique

    Energy Technology Data Exchange (ETDEWEB)

    Pochat Bohatier, C

    1999-12-06

    The aim of the study was to examine emissions of volatile organic compounds (VOCs) during acetic (acid) fermentation. The first part of the study presents the methodology developed to reproduce production cycles for spirit vinegar and to analyse gas effluents. The second part describes the origin and quantification of the emissions (ethanol, acetic acid, acetaldehyde and ethyl acetate). The acetic acid is produced by bacterial metabolism while the ethyl acetate is a result of the chemical reaction of esterification. By modelling the emissions during batch processing we were able to identify the various parameters involved when VOCs are carried along by the fermentation gases. The quantities of ethyl acetate depend on the length of time the diluted alcohol is stored, and on its composition. By using a fed-batch method with a continuous supply of ethanol we could reduce alcohol emissions. The third part of the study develops the kinetics studies carried out to adapt the fed-batch process to acetic acid fermentation. The influence of ethanol, either in terms of deficiency or inhibition, is minimized between 8 and 16 g.1-1. A study of the growth rate of bacteria in relation to the amount of acetic acid showed that the latter was highly inhibitive. There is a critical concentration of acetic acid at which the growth of bacteria stops, and the death rate of the culture increases rapidly. The latter depends on the composition of the culture's medium; the corresponding pH of the concentration is between 2.25 and 2.28. By limiting the formation of ethyl acetate in the diluted alcohol and by controlling the concentration of ethanol at 16 g.l -1 per fermentation, the VOC emissions are reduced by 30% and the yield increases as a result. (author)

  15. Effects of atmospheric fallouts of sulfur and nitrogen on soils and fresh waters in France; Effets des depots atmospheriques de soufre et d'azote sur les sols et les eaux douces en France

    Energy Technology Data Exchange (ETDEWEB)

    Le Gall, A.Ch.

    2004-11-15

    The sulfur oxides, nitrogen oxides, the ammonia and the chlorine emitted in the environment by human activities contribute to the soils and waters acidity. After a presentation of the acidification and the eutrophication, the author describes and qualifies the mechanisms. In a second part she discusses the mathematical models of the acidification and the eutrophication, the biological criteria and the uncertainties. The last part presents the french situation and general recommendations on land restoration. (A.L.B.)

  16. Lichens and air pollution: effect of SO'' on the growth of Hypogymnia physodes (L. ) Nyl. Lichens et pollution atmospherique: l'effet du SO/sub 2/ sur les soredies k Hypogymnia physodes (l. ) Nyl

    Energy Technology Data Exchange (ETDEWEB)

    Margot, J

    1972-01-01

    Experiments were performed to determine the relative susceptibility of lichens to the effect of sulfur dioxide. Attention was focused on Hypogymnia physodes, with brief studies on several other species. Evernia prunastri and Parmeliopsis ambigua were more sensitive to sulfur dioxide than Hypogymnia physodes. 145 references, 33 figures, 43 tables.

  17. Toward an estimation of daily european CO{sub 2} fluxes at high spatial resolution by inversion of atmospheric transport; Vers une estimation des flux de CO{sub 2} journaliers europeens a haute resolution par inversion du transport atmospherique

    Energy Technology Data Exchange (ETDEWEB)

    Carouge, C

    2006-04-15

    Since the end of the 1980's, measurements of atmospheric carbon dioxide have been used to estimate global and regional fluxes of CO{sub 2}. This is possible because CO{sub 2} concentration variation is directly linked to flux variation by atmospheric transport. We can find the spatial and temporal distribution of fluxes from concentration measurements by 'inverting' the atmospheric transport. Until recently, most CO{sub 2} inversions have used monthly mean CO{sub 2} atmospheric concentration measurements to infer monthly fluxes. Considering the sparseness of the global CO{sub 2} measurement network, fluxes were a priori aggregated on sub-continental regions and distributed on a fixed spatial pattern within these regions. Only one flux coefficient per month for each region was optimized. With this strong constraint, estimated fluxes can be biased by non-perfect distribution of fluxes within each region (aggregation error). Therefore, flux estimation at model resolution is being developed where the hard constraint of a fixed distribution within a region is replaced by a soft constraint of covariances between flux uncertainties. The use of continuous observations from an increasing number of measurement sites offers a new challenge for inverse modelers. We investigate the use of daily averaged observations to infer daily CO{sub 2} fluxes at model resolution over Europe. We have developed a global synthesis Bayesian inversion to invert daily fluxes at model resolution (50 x 50 km over Europe) from daily averaged CO{sub 2} concentrations. We have obtained estimated fluxes for the year 2001 over Europe using the 10 European continuous sites from the AEROCARB network. The global atmospheric model LMDZt is used with a nested grid over Europe. It is necessary to add a priori spatial and temporal correlations between flux errors to constrain the Bayesian inversion. We present the impact on estimated fluxes of three different spatial correlations based on distance between pixels, climate and vegetation distribution over Europe. To study the potential of this method, we used synthetic data generated from forward simulations of LMDZt (driven by flux fields generated from the biosphere model ORCHIDEE). We have found that the current network is not dense enough to constrain fluxes at model resolution. However, fluxes that are aggregated spatially over a region of 850 x 850 km in the Western Europe and temporally over 8-10 days compare very well with the ORCHIDEE fluxes. Preliminary inversion results using real data indicate that synoptic variations of estimated fluxes are in phase with the variations of the ORCHIDEE biosphere model flux and the variations observed in atmospheric concentrations. However, the quality of the flux estimates are highly dependant on transport model errors and in particular, on the quality of modelling small scale transport. Moreover, fossil fuel emissions are prescribed in this inverse model and the quality of their distribution is shown to be crucial. Data selection also has a large impact on estimated fluxes. The use of the daytime only data to calculate daily averaged concentrations greatly improves the estimated fluxes by reducing bias inferred from model transport errors. (author)

  18. Study of short time effect on health of a local air pollution source. Epidemiological approach; Etude des effets a court terme sur la sante d'une source locale de pollution atmospherique. Approche epidemiologique

    Energy Technology Data Exchange (ETDEWEB)

    Guzzo, J.Ch. [Institut National de Veille Sanitaire, Reseau National de Sante Publique, 94 - Saint-Maurice (France)

    2000-07-01

    This document applies to health professionals who are facing with a problem of risks evaluation relative to a local source of air pollution and envisage to realize an epidemiological study. In this document, only the short term effects are considered and the situations of accidental pollution are not treated. Without being a methodological treatise it can be a tool to better understand the constraints and the limits of epidemiology to answer the difficult question of the impact evaluation on health of populations living near a local source of air pollution. (N.C.)

  19. Study of the coastal atmospheric boundary layer during ESCOMPTE 2001. Evaluation and improvement of the efficiency of a UHF radar; Etude de la couche limite atmospherique cotiere durant ESCOMPTE 2001. Evaluation et amelioration des performances d'un radar UHF

    Energy Technology Data Exchange (ETDEWEB)

    Puygrenier, V

    2005-12-15

    Forecasting of pollution events was the main objective of the ESCOMPTE-2001 campaign, which took place in the Marseille/Fos/Berre heterogeneous area (southeastern France) in the early summer 2001. This goal requires good understanding and taking into account, by physico-chemical numerical models, of the physical processes in the Atmospheric Boundary Layer (ABL), in which pollutants are emitted, transported and diffused. In the ESCOMPTE-2001 campaign context, this work was devoted to study the low troposphere during sea breeze events, related to meteorological conditions responsible for poor air quality of coastal areas. It presents notably an oscillation of the sea breeze intensity and competitions of locals and regional sea breeze, which change the advective time of the marine air above the continental surface and thus influence the ABL development and its pollutants concentration. This study is based principally on the network of four UHF wind profilers radars set up on the coastal area of Marseille/Fos/Berre, allowing a continuous three-dimensional description of the sea breeze flow and the ABL. For the needs of this phenomenological work, methodological developments was realized to improve the measurement of ABL turbulent properties with UHF radars (terms of turbulent kinetic energy budget) and the use of wind profilers network for the study of pollutants plumes trajectory-graphy. (author)

  20. Inverse modeling for the optimization of primary sources of atmospheric pollution at a regional scale; Modelisation inverse pour l'optimisation des sources primaires de pollution atmospherique a l'echelle regionale

    Energy Technology Data Exchange (ETDEWEB)

    Pison, I

    2005-12-15

    Atmospheric pollution at a regional scale is the result of various interacting processes: emissions, chemistry, transport, mixing and deposition of gaseous species. The forecast of air quality is then performed by models, in which the emissions are taken into account through inventories. The simulated pollutant concentrations depend highly on the emissions that are used. Now inventories that represent them have large uncertainties. Since it would be difficult today to improve their building methodologies, there remains the possibility of adding information to existing inventories. The optimization of emissions uses the information that is available in measurements to get the inventory that minimizes the difference between simulated and measured concentrations. A method for the inversion of anthropogenic emissions at a regional scale, using network measurements and based on the CHIMERE model and its adjoint, was developed and validated. A kriging technique allows us to optimize the use of the information available in the concentration space. Repeated kriging-optimization cycles increase the quality of the results. A dynamical spatial aggregation technique makes it possible to further reduce the size of the problem. The NO{sub x} emissions from the inventory elaborated by AIRPARIF for the Paris area were inverted during the summers of 1998 and 1999, the events of the ESQUIF campaign being studied in detail. The optimization reduces large differences between simulated and measured concentrations. Generally, however, the confidence level of the results decreases with the density of the measurement network. Therefore, the results with the higher confidence level correspond to the most intense emission fluxes of the Paris area. On the whole domain, the corrections to the average emitted mass and to the matching time profiles are consistent with the estimate of 15% obtained during the ESQUIF campaign. (author)

  1. Evaluation of sanitary impact of urban air pollution. Agglomeration of Bayonne impact at short and long term; Evaluation de l'impact sanitaire de la pollution atmospherique urbaine. Agglomeration de Bayonne impact a cour et long terme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-06-15

    A health impact assessment of air pollution based on the I.n.V.S. guidelines has been conducted in Bayonne according to the regional Plan for the quality of air in the region of Aquitaine. It has been carried out in 16 cities homogeneously exposed, belonging to Bayonne agglomeration, representing a study population of 148,742 inhabitants. Atmospheric pollution indicators analyzed are ozone, nitrogen dioxide and particles having diameter below 10 {mu}m. Short-term impact of atmospheric pollution has been estimated in term of mortality (total, cardiovascular and respiratory mortality) and on hospital intakes (for respiratory, cardiovascular and cardiac reasons) attributable to air pollution. Long term impact was also assessed by the number of deaths due to atmospheric pollution. In 2001, the atmospheric pollution has directly been responsible in the studied area for 20 anticipated deaths. A decrease by 25% of the pollutants could allow avoiding half of the premature deaths and hospital intakes attributable to air pollution. Concerning long term effects, a decrease by 5 {mu}g/m{sup 3} of the annual mean of PM{sub 10} could allow avoiding 32 deaths per year. These results should be interpreted with care because of the limits of the method. However, they show that air pollution impact is non negligible even in a small agglomeration like Bayonne, since everyone is exposed to air pollution. They also suggest that a policy of atmospheric pollution reduction only based on not exceeding the standard levels would not have the expected benefits on the public health point of view. To decrease at the source the everyday and total pollutants emissions would be more efficient. (author)

  2. Evaluation of sanitary impact of urban air pollution. Montpellier area impact at short and long term; Evaluation de l'impact sanitaire de la pollution atmospherique urbaine. Zone de Montpellier impact a court et long terme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    The assessment of the health impact of urban atmospheric pollution in Montpellier agglomeration has been carried out as part of the development of atmosphere protection plan. The study, based on the four standardised steps of health risk assessment, has two objectives. First of all, it aims at assessing the short-term impact of atmospheric pollution on mortality (total, cardiovascular and respiratory mortality) and on hospital intakes (for respiratory, cardiovascular and cardiac reasons). Second, the long-term impact is assessed by the number of deaths due to atmospheric pollution. On the other part, the computation of the expected health gain, as a function of different scenarios of atmospheric pollutants reduction, can allow to plan air quality improvement measures. The assessment of atmospheric pollution impact has been carried out in eleven cities, homogeneously exposed, belonging to Montpellier agglomeration (Castelnau-le-Lez, Clapiers, Le Cres, Grabels, Jacou, Juvignac, Montferrier-sur-Lez, Montpellier, Saint-Clement-de-Riviere, Saint- Jean-de-Vedas, Vendargues). It is based on the analysis of mortality figures during two years (1999 and 2000) and of hospital intakes during four years (from 1999 to 2002). The studied population is made up 288.059 inhabitants. Atmospheric pollution indicators analysed are ozone, nitrogen dioxide, sulphur dioxide and particles having diameter below 10 {mu}m. Every year, the atmospheric pollution is directly responsible in the studied area of 34 anticipated deaths, among including 13 for cardiovascular reason and 4 for respiratory reason. For morbidity, it generates every year 79 hospital admissions for cardiovascular reason, 15 for cardiac reason, 9 for respiratory reason for older than 65 years old people and 4 for 15-64 years old people. Older than 65 years old people are proportionally more impacted. These events could theoretically be avoided with pollution levels in the order of those reached the less polluted days. Health gains connected with a reduction of the pollution have been computed according to two scenarios. The short term health gains are lower with a suppression of the pollution peaks than with a 25% decrease of the background pollution. The long-term health gains are also more important when the mean levels of pollution are decreased by 25% (40 deaths avoided) or by 5 {mu}g/m{sup 3} (37 deaths avoided) than an annually decrease according to the European standards levels of 2010 (20 deaths avoided). Even for low exposure levels, the health impact of the atmospheric pollution has already been shown from another source. This study does not aim at showing it, but at quantifying this impact at the local extent. It also aims at allowing authorities to establish a policy for the reduction of the pollution based on local health arguments. Anyway, a policy of atmospheric pollution reduction only based on not exceeding the standard levels would not have the expected benefits on the public health point of view. To decrease at the source the every day and total pollutants emissions would be more efficient. The atmospheric pollution in Montpellier agglomeration is mainly due to road traffic. These emissions should be decreased first of all. (author)

  3. Evaluation of urban air pollution impact. Brest and Nantes impact at long term; Evaluation de l'impact sanitaire de la pollution atmospherique urbaine. Brest et Nantes impact a long terme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    The assessment for Brest and Nantes of the health impact in 1999 of chronic exposure to air pollution relies on four stages: health outcome identification, the selection of exposure-response functions, exposure assessment and risk characterization. The study characterizes: - the health gain due to a 25% decrease in air pollution levels; - the expected health impact of a 15% rise in air pollution levels. The results give the number of deaths attributable to air pollution. As for the health gain, the gain in days of life expectancy is also calculated. The study for Brest relies on one single exposure-response function. Concerning Nantes, the air control network is more complete and allows to use four exposure-response functions. The health gain due to a 25% decrease in air pollution levels is interpreted as a prudent evaluation of the health impact of air pollution. The estimated number of deaths due to the impact is around 38 (23 - 53) for Brest and around 40 (14 - 65) for Nantes. It means a decrease in the lifespan of 48 (29 - 68) days for Brest and 51 (17 - 84) days for Nantes. The uncertainty about exposure evaluation, the use of American exposure-response functions and of strong hypotheses to calculate the lifespan reduction generate more errors and uncertainty than for short term health impact assessment. (author)

  4. The multimedia models for the evaluation of exposure bond to the atmospheric emissions of classified installations; Les modeles multimedia pour l'evaluation des expositions liees aux emissions atmospheriques des installations classees

    Energy Technology Data Exchange (ETDEWEB)

    Bonnard, R

    2001-12-15

    Risk assessment and environmental impacts studies are realized to preserve the public health. Today one of the most used approach is the use of an atmospheric dispersion model to assess the risks. The data are then injected in a calculation software of exposure bond to polluted soils, to evaluate the risks of non direct exposure. This report details and evaluates the models corresponding to the need: the methodology for assessing Health Risks associated with multiple pathways of exposure to combustor, human health risk assessment proto col for hazardous waste combustion facilities, EUSES, CALTOX, MEPAS, MEND-TOX, RESRAD, MMSOILS, FRAMES-HWIR, PC-GEMS and TRIM. (A.L.B.)

  5. Characterization of the atmospheric pollution level in Sfax (Tunisia): influence of sources and meteorological factors; Caracterisation du niveau de pollution atmospherique dans la ville de Sfax (Tunisie): influence des sources et des facteurs meteorologiques

    Energy Technology Data Exchange (ETDEWEB)

    Azri, Ch.; Maalej, A.; Medhioub, K. [Ecole Nationale d' ingenieurs de Sfax, Unite de Recherche Etude et Gestion des Environnements Cotiers et Urbains (Tunisia); Tlili, A. [Faculte des Sciences de Sfax, Dept. de Geologie (Tunisia)

    2002-01-01

    This study held in Sfax City (Tunisia), showed that the atmospheric pollution level is strongly influenced by industrial sources, obstacles and meteorological factors. The factory of phosphate treatment 'SIAPE' displayed the main polluting source in the City. It is the principal issuing of SO{sub x} and toxic metals. The phosphogypsum deposit displayed an obstacle to the atmospheric diffusion of pollutants. Their stagnation is accentuated under smoky conditions. Several episodes of SO{sub 2} and dust are attributed to the effect of marked thermal inversions and the sirocco wind. The limited influence of traffic was proved by the registration of NO{sub x}, which showed low concentrations. It is conditioned by the change of fashion life of people and their customs of work (Ramadan month, agricultural activities). As a result, the adequate treatment of atmospheric industrial emanations (notably those of SIAPE) and the evacuation of artificial obstacles have to be considered. (authors)

  6. Opinions and attitudes on the wastes management, the eco-products consumption and the atmospheric pollution; Opinions et attitudes sur la gestion des dechets, sur la consommation des eco-produits et sur la pollution atmospherique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    This document presents the results of the inquiry on the ''way of life and french aspiration'' concerning the energy. The inquiry was realized at the beginning of 2001 on a sample of 2000 people. The questions dealt with the three following topics: the french attitude facing the atmospheric pollution, consumption and the environment preservation, the opinion on the wastes management. (A.L.B.)

  7. Atmospheric pollution, eco-products, wastes management: some opinions and attitudes at the beginning of 2002; Pollution atmospherique, eco-produits, gestion des dechets: quelques opinions et attitudes au debut 2002

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This document presents the results (statistical data) to the questions asked by the ADEME in the inquiry of the CREDOC concerning the ''French way of life and aspirations'' and realized in the beginning of the year 2002. The questions dealt with the following five topics: the french attitude facing the atmospheric pollution; the renouncing of the vehicle during the days of high urban pollution; the French and the remote-working; the consumption and the environment control. (A.L.B.)

  8. Detection, in real time, of metallic pollutants present in the industrial atmospheric effluents by inductively coupled plasma torch; Detection, en temps reel, d'elements metalliques presents dans les rejets atmospheriques industriels par torche a plasma a couplage inductif

    Energy Technology Data Exchange (ETDEWEB)

    Vacher, D.

    2001-12-15

    This work is devoted to the development of a process of detection in real time of metallic pollutants present in industrial atmospheric effluents. The method of measurement is the atomic spectrometry of emission coupled to an ICP torch (Inductively coupled Plasma). The technology of the fluidized beds is used as system of introduction of the metallic particles into the ICP torch, the interest of the principle of detection resting on the stamping from the usual procedure of calibration of the analytical system. The results are presented in two parts. The first relates to the diagnosis of plasmas formed with various mixtures of N{sub 2}/O{sub 2} which one corresponds to pure air, the second presents the setting process of detection in real time starting from the intensities ratios of the spectral lines of the metallic element with those of the plasma-producing element (argon or pure air) The study of the diagnosis of plasmas made up of mixtures N{sub 2}/O{sub 2} relates to the determination of the atomic excitation temperature from the spectral lines of the copper element and the evaluation of the thermal disequilibrium q Te/Th. This last is obtained by considering the mass enthalpy of various mixtures N{sub 2}/O{sub 2}. The existence of a small thermal disequilibrium is highlighted. The study of detection in real time by ICP torch, without calibration of the system, is based on three points: - spectroscopic data processing to determine the values of the intensities ratios of spectral lines; - the insertion of the intensities ratios and the characteristics of plasma (argon or pure air) into a calculation code of plasma composition; - the comparison of the mass flux values of the metallic pollutants, in real time, obtained by experiments with those resulting from the elutriation calculation, term which defines the phenomenon of entrainment of the particles out of the fluidized bed. The results made it possible to show the similarity of the analytical system response between the use of argon plasma and that of air. (author)

  9. Unified fit of solar and atmospheric neutrinos: towards the MNSP matrix; Ajustements globaux des resultats des experiences de neutrinos solaires et atmospheriques: vers la determination de la matrice de melange des neutrinos (dite MNSP)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-01-01

    Present solar and atmospheric neutrino give a strong indication that neutrinos oscillate between the three active species. This is the first step towards the determination of their mass. But we have also to determine the 3 x 3 neutrino mixing matrix (3 angles and one or several phases linked to CP violation), called MNSP (Maki-Nakagawa-Suzuki-Pontecorvo) and similar to the quark mixing matrix, called CKM (Cabibbo-Kobayashi-Maskawa). The purpose of the colloquium (one day) is to give an overview of the present situation and what progresses are expected in the forthcoming years. 3 guidelines: pedagogical approach, critical review of the experimental situation and of the different analyses, lookout to the future. (author)

  10. Evaluation of the sanitary impact of urban air pollution. Update version of the methodological guide; Evaluation de l'impact sanitaire de la pollution atmospherique urbaine. Version actualisee du guide methodologique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-03-15

    In order to bring a help to the evaluation of effects of air quality on health, the Institute of Sanitary surveillance published in 1999 a method guide for the realisation of sanitary impact evaluations of the urban air pollution. This work to prepare to an update version of the guide presents the first recommendations that can be made today for the realisation of sanitary impact evaluations at short and long term at a local level, taking into account the knowledge evolution. (N.C.)

  11. Evaluation of sanitary impact of urban air pollution. Agglomeration of Agen impact at short and long term; Evaluation de l'impact sanitaire de la pollution atmospherique urbaine. Agglomeration d'Agen impact a court et long terme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    A health impact assessment of air pollution based on the I.n.V.S. guidelines has been conducted in Agen according to the regional Plan for the quality of air in the region of Aquitaine to assess short term effects of pollutants on morbidity (hospital admissions in 2002) and mortality (deaths in 2001), and long-term effects on mortality. This study is based on the four standardised steps of health risk assessment. It has been carried out in 8 cities homogeneously exposed, belonging to Agen agglomeration, representing a study population of 60,515 inhabitants. Atmospheric pollution indicators analysed are ozone and particles having diameter below 10 {mu}m. Short-term impact of atmospheric pollution has been estimated in term of mortality (total, cardiovascular and respiratory mortality) and on hospital intakes (for respiratory, cardiovascular and cardiac reasons) attributable to air pollution.Long-term impact was also assessed by the number of deaths due to atmospheric pollution. In 2001, the atmospheric pollution has directly been responsible in the studied area of 4 anticipated deaths, including 2 for cardiovascular reason. A decrease by 25% of the pollutants could allow avoiding 2 premature deaths per year among the 4 attributable to air pollution. Concerning long-term effects, a decrease by 5 {mu}g/m{sup 3} of the annual mean of P.M.10 would allow avoiding 11 premature deaths per year. The results of this study should be interpreted with care because of the limits of the method. However, they show that air pollution can have a health impact even in a small city like Agen, since everyone is exposed to air pollution. (author)

  12. Evaluation of sanitary impact of urban air pollution. Agglomeration of Pau impact at short and long term; Evaluation de l'impact sanitaire de la pollution atmospherique urbaine. Agglomeration de Pau impact a cour et long terme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    A health impact assessment of air pollution based on the I.n.V.S. guidelines has been conducted in Pau according to the regional Plan for the quality of air in the region of Aquitaine. Short-term effects of pollutants on morbidity (hospital admissions in 2002) and mortality (deaths in 2001) have been estimated. Long-term effect on mortality was also assessed. This study is based on the four standardised steps of health risk assessment. It has been carried out in twenty-nine cities homogeneously exposed, belonging to Pau agglomeration, i.e. a study population of about 150,000 inhabitants. Atmospheric pollution indicators analysed are ozone, nitrogen dioxide, and particles having diameter below 10 {mu}m. Short-term impact of atmospheric pollution has been estimated in term of mortality (total, cardiovascular and respiratory mortality) and on hospital intakes (for respiratory, cardiovascular and cardiac reasons) attributable to air pollution. Long term impact was also assessed by the number of deaths due to atmospheric pollution. In 2001, the atmospheric pollution has directly been responsible in the studied area for 17 anticipated deaths, including 7 for cardiovascular reason and 2 for respiratory reason. Concerning morbidity, it generated 20 hospital admissions for cardiovascular reason in 2002, 11 for cardiac reason, and 7 for respiratory reason among elderly people. Regarding long-term health gains, an annually decrease according to the European standards levels of 2010 could allow avoiding 12 deaths per year, and a decrease by 30% of the pollutants could allow avoiding 33 premature deaths per year. This study shows that, even if the relative risks associated to air pollution are quite low, the number of attributable cases is non negligible since everyone is exposed to air pollution. It also shows that a policy of atmospheric pollution reduction only based on not exceeding the standard levels would not have the expected benefits on the public health point of view. To decrease at the source the every day and total pollutants emissions would be more efficient. (author)

  13. Evaluation of urban air pollution impact. Agglomeration of Toulon impact at short and long term; Evaluation de l'impact sanitaire de la pollution atmospherique urbaine. Agglomeration de Toulon impact a cour et long terme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    A health impact assessment of air pollution based on the I.n.V.S. guidelines has been conducted in Toulon according to the Regional Plan for the quality of air in the region of Provence-Alpes-Cote d Azur. Short-term effects on morbidity (hospital admissions) and mortality and long-term effects on mortality were estimated. Four cities were included in the study area: Toulon, La Garde, La Seyne-sur-mer and La Valette-du-Var (population: 267.808 inhabitants. Two periods of study have been defined: 1999 for the mortality analysis and 2000 for the morbidity analysis and the long- term effects. For 1999, number of advanced deaths due to air pollution is around 84 for total mortality including 30 deaths due to cardio-vascular diseases and 10 deaths due to respiratory diseases. The different scenarios of air pollution reduction showed that the most effective ones are those which lead to reduce of 25% the mean of the involved pollutant. Regarding long-term effects, the different scenario showed that the respect of the European Community limits value for the year 2010 would allow to avoid 118 deaths over one year. Results showed that air pollution are even resulting in health effects for some levels of pollution lower than current French limits. The most effective actions should therefore associate reduction of the source emissions on a daily basis and decrease of the over-limits levels of pollution. (author)

  14. Evaluation of sanitary impact of urban air pollution. Agglomeration of Perigueux impact at short and long term; Evaluation de l'impact sanitaire de la pollution atmospherique urbaine. Agglomeration de Perigueux impact a court et long terme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-15

    A health impact assessment of air pollution based on the I.n.V.S. guidelines has been conducted in Perigueux according to the regional Plan for the quality of air in the region of Aquitaine. It has been carried out in 5 cities homogeneously exposed, belonging to Perigueux agglomeration, representing a study population of 52,948 inhabitants. Atmospheric pollution indicators analysed are ozone, nitrogen dioxide and particles having diameter below 10 {mu}m. Short-term impact of atmospheric pollution has been estimated in term of mortality (total, cardiovascular and respiratory mortality) and on hospital intakes (for respiratory, cardiovascular and cardiac reasons) attributable to air pollution. Long term impact was also assessed by the number of deaths due to atmospheric pollution. In 2001, the atmospheric pollution has directly been responsible in the studied area for 5 anticipated deaths. A decrease by 25% of the pollutants could allow avoiding half of the premature deaths and hospital intakes attributable to air pollution. Concerning long term effects, a decrease by 5 {mu}g/m{sup 3} of the annual mean of P.M.10 could allow avoiding 10 deaths per year. These results should be interpreted with care because of the limits of the method. However, they show that air pollution can have an impact even in a small agglomeration like Perigueux, since everyone is exposed to air pollution. They also suggest that a policy of atmospheric pollution reduction only based on not exceeding the standard levels would not have the expected benefits on the public health point of view. To decrease at the source the every day and total pollutants emissions would be more efficient. (author)

  15. Ozone production by pulsed dielectric barrier discharges in air at atmospheric pressure; Efficacite de production d'ozone par decharge electrique pulsee sur barriere isolante dans l'air a pression atmospherique

    Energy Technology Data Exchange (ETDEWEB)

    Odic, E.; Karimi, Ch. [Supelec, Service Electrotechnique et Electronique Industrielle, 91 - Gif-sur-Yvette (France); Dhainaut, M.; Goldman, A.; Goldman, M. [Supelec, Laboratoire de Physique des Gaz et des Plasmas (Univ. Paris-Sud/CNRS), Equipe Decharges Electriques et Environnement, 91 - Gif sur Yvette (France)

    2005-02-01

    Non-thermal plasmas have been extensively studied these past 20 years from a theoretical point of view, but also for practical applications. Atmospheric pressure electrical discharges appear as promising technologies for gas phase and aqueous phase pollution control applications. In such arrangements, arcing i.e. transition to thermal plasma, is classically prevented either by application of short high voltage pulses or by insulating one or both electrodes with a dielectric material. The aim of this paper is to report recent results on ozone formation indicating a significant increase of the energy yields by coupling these two techniques. The chemical behaviour of the discharge is correlated to its electrical characteristics. The physical role plaid by the dielectric surface is highlighted and an interpretation is proposed. (authors)

  16. L'IIASA and the integrated simulation of the trans-border atmospheric pollution assessment and evaluation; L'IIASA et la modelisation integree de la pollution atmospherique transfrontiere. Bilan et evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Soleille, S.; Brignon, J.M.; Farret, R.; Landrieu, G.; Le Gall, A.C.; Rouil, L

    2003-09-15

    The RAINS model is an integrated evaluation model for many pollutants and many effects, developed by he IIASA. This model studies the emissions of 4 atmospheric pollutants (nitrogen oxides, sulfur oxides, ammonium and volatile organic compounds) and the necessary costs to reduce them and the dispersion of these pollutants and their effects (tropospheric ozone formation, acidification and eutrophication). The model can be used in activities scenario mode (energy, agriculture, transports...) to calculate the emissions and their effects or in optimization mode to calculate strategies of emissions control from environmental constraints. (A.L.B.)

  17. Epidemiological surveillance - air and health. Surveillance of effects on health linked to air pollution; Surveillance epidemiologique air et sante. Surveillance des effets sur la sante lies a la pollution atmospherique en milieu urbain

    Energy Technology Data Exchange (ETDEWEB)

    Quenel, Ph; Cassadou, S; Eilstein, D; Filleul, L; Le Goaster, C; Le Tertre, A; Medina, S; Pascal, L; Prouvost, H; Saviuc, Ph; Zeghnoun, A [Institut National de Veille Sanitaire, 94 - Saint Maurice (France); Declerq, Ch [Observatoire Regional de Sante Nord Pas de Calais (France)

    1999-03-01

    In the field of air pollution, the France is the first country to be endowed with a device of epidemiological surveillance allowing to to evaluate and monitor the impact of urban air pollution on the health of population. This new approach is based on the analysis of relationship between pollution indicators and health indicators, it leads to confirm the partnership between actors of environment and health, at the national level as well at the local level. It confirms the development of assessment in the field of environmental health. (N.C.)

  18. Modelling the long-range transport. Atmospheric model from the Oslo EMEP-W center; Modelisation du transfert a longue distance modele atmospherique du centre Emep-W- a Oslo

    Energy Technology Data Exchange (ETDEWEB)

    Joffre, S. [Institut Meteorolique de Finlande Geographical Research Vuorikatu, Helsinki (Finland)

    1997-12-31

    In the framework of the European Monitoring and Evaluation Program (EMEP) concerning transfrontier air pollution in Europe, a model has been developed which gives, based on pollution emission and meteorological data, monthly and annual values for the atmospheric content of ten major pollutants, the deposited dry and wet compounds, and the source allocations. Physical principles of the model and its validation are described

  19. Inverse modeling for the optimization of primary sources of atmospheric pollution at a regional scale; Modelisation inverse pour l'optimisation des sources primaires de pollution atmospherique a l'echelle regionale

    Energy Technology Data Exchange (ETDEWEB)

    Pison, I.

    2005-12-15

    Atmospheric pollution at a regional scale is the result of various interacting processes: emissions, chemistry, transport, mixing and deposition of gaseous species. The forecast of air quality is then performed by models, in which the emissions are taken into account through inventories. The simulated pollutant concentrations depend highly on the emissions that are used. Now inventories that represent them have large uncertainties. Since it would be difficult today to improve their building methodologies, there remains the possibility of adding information to existing inventories. The optimization of emissions uses the information that is available in measurements to get the inventory that minimizes the difference between simulated and measured concentrations. A method for the inversion of anthropogenic emissions at a regional scale, using network measurements and based on the CHIMERE model and its adjoint, was developed and validated. A kriging technique allows us to optimize the use of the information available in the concentration space. Repeated kriging-optimization cycles increase the quality of the results. A dynamical spatial aggregation technique makes it possible to further reduce the size of the problem. The NO{sub x} emissions from the inventory elaborated by AIRPARIF for the Paris area were inverted during the summers of 1998 and 1999, the events of the ESQUIF campaign being studied in detail. The optimization reduces large differences between simulated and measured concentrations. Generally, however, the confidence level of the results decreases with the density of the measurement network. Therefore, the results with the higher confidence level correspond to the most intense emission fluxes of the Paris area. On the whole domain, the corrections to the average emitted mass and to the matching time profiles are consistent with the estimate of 15% obtained during the ESQUIF campaign. (author)

  20. A campaign to study atmospheric pollution at the regional scale: the Escompte programme; Une experience d'etude de la pollution atmospherique a l'echelle regionale. Le programme Escompte

    Energy Technology Data Exchange (ETDEWEB)

    Durand, P. [Meteo-France - Centre National de Recherches Meteorologiques, Centre National de la Recherche Scientifique (CNRS URA 1357), 31 - Toulouse (France); Cros, B. [Observatoire Midi-Pyrenees, Lab. d' Aerologie, Centre National de la Recherche Scientifique (CNRS UMR 5560), 31 - Toulouse (France)

    2004-02-01

    The Escompte programme was set up to improve and validate regional scale chemistry-transport numerical models. During summer 2001, an ambitious field campaign collected data on the meteorological and chemical parameters of the atmosphere during some photo-oxidant pollution events. Performed in the region of Marseille city and Berre lake, this campaign deployed a huge quantity of instruments, and constitutes one of the major operations in this field. (authors)

  1. Evaluation of sanitary impact of the urban air pollution. Avignon area impact at short and long term; Evaluation de l'impact sanitaire de la pollution atmospherique urbaine. Zone d'Avignon impact a court et long terme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    An health impact assessment of air pollution based on the I.n.V.S. guidelines has been conducted in Avignon according to the Regional Plan for the quality of air in the region of Provence Alpes Cote d'Azur. Short term impact of atmospheric pollution has been estimated in term of mortality (total, cardiovascular and respiratory mortality) and hospital admissions (for respiratory, cardiovascular and cardiac reasons) attributable to air pollution. Long-term impact was also assessed by the number of deaths due to atmospheric pollution. The study has been carried out in seven cities homogeneously exposed belonging to Vaucluse (Avignon, Le Pontet, Morieres les Avignon, Sorgues and Vedene) and two cities of the Gard department (les Angles and Villeneuve les Avignon) representing a study population of 153,624 inhabitants. Two period of study have been defined: period 1999-2000 for short and long term evaluations on the mortality and the year 2001 for the morbidity analysis. This study rests on methodological principles of E.I.S. (evaluation of sanitary impact) of urban air pollution whom methodology is in four steps: identification of dangers, exposure estimation, choice of exposure-risk relationship and risk characterisation. The pollutions indicators are built from four pollutants nitrogen dioxide, ozone, sulfur dioxide and PM{sub 10}. The exposure-risk relationships used come from epidemiological studies realised in general population, by preferring the multi centers studies and European ones. The number of deaths by year due to air pollution is 23, whom 10 by cardiovascular diseases, 2 by respiratory diseases. The most efficient scenario are these ones corresponding to air pollution decreases of 25% in the considered pollutant. About the long term sanitary benefits, the different scenario show that the European norm forecasted for 2005 is respected. The respect of the European norm expected for 2010 should allow to avoid 10 deaths on the totality of registered deaths on a year, whereas a 25% decrease of the year average should allow to avoid 25 ones. According to the uncertainties and limits of the used methodology, the results must be interpreted as order of magnitude of the impact of air pollution on population health in the studied area. This study shows that even if the risks relative to air pollution are low, the proportion of exposed persons leads to a non negligible impact on mortality. It shows that sanitary effects appear at levels under that these ones actually measured and then the most efficient measures would be these ones that would associate a reduction of emissions at the source with an important reduction of the pollution peaks number. (N.C.)

  2. Modeling of atmospheric pollution at the regional scale: application to the Esquif campaign; Modelisation a l'echelle regionale de la pollution atmospherique: application a la campagne Esquif

    Energy Technology Data Exchange (ETDEWEB)

    Sarrat, C.

    2003-06-01

    The Esquif experimental campaign (study and simulation of air quality in Ile-de-France (Paris region, France)) took place between 1998 and 2000 with the aim of better understanding the dynamical and chemical processes leading to atmospheric pollution peaks in Paris. The construction of a rich and diversified database (12 periods of intensive monitoring (PIM)) has been implemented with the aim of improving the existing chemical-transport models in general and air quality forecasting models in particular. In the framework of this study, the data collected during PIM 2 and 6 were used for the validation and analysis of situations of intensive pollution, simulated with the meso-scale numerical meteorological and chemical model Meso-NHC. The validation of both the dynamic fields (temperature and potential temperature, wind, height of the boundary layer) and the chemical fields (mainly O{sub 3}, NO{sub x}, NO{sub y}, PAN, isoprene) of the model allows to discuss some of the parameters of the model such as the initialization, the boundary forcing and the resolution. Then, a study of the dynamical processes allows to analyze the formation and reinforcement of the pollution conditions. Stress is put on the interaction of the regional scale processes with the photochemical pollution events. In this framework, the dynamical-chemical interaction processes are analyzed in detail, in particular when pollution levels are reinforced by the intrusion of residual ozone inside the convective boundary layer, dragged by the turbulence. Also, the impact of the urban hot island and of the urban wind on the redistribution of primary and secondary pollutants are considered. An analysis of the impact of hydrocarbons of biogenic origin on the ozone concentrations with respect to the temperature and to the presence of primary compounds has been performed for the PIM 2 and 6 of the Esquif campaign. (J.S.)

  3. Ambient air pollution and hospitalization for congestive heart failure among elderly people in seven large US cities; Pollution atmospherique ambiante et hospitalisations pour insuffisance cardiaque congestive chez les personnes agees dans sept grandes villes des Etats-Unis

    Energy Technology Data Exchange (ETDEWEB)

    Morris, R.D.; Naumova, E.N.; Munasinghe, R.L.M.

    2001-01-01

    The aim of this study is the temporal associations between the urban atmospheric pollution, in particular the carbon monoxide, and the hospitalization for congestive heart failure in elderly people, in seven large US cities. (A.L.B.)

  4. Opinions of the French on the atmospheric pollution, the wastes management and the eco-products; Opinions des francais sur la pollution atmospherique, la gestion des dechets et les eco-produits

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-06-01

    Five main opinions can be presented from the answers analysis to the inquiry realized in 1999 by the ADEME on the French way of life and aspirations. The French think that the atmospheric pollution is dangerous for the health and that they are badly informed about the air quality of their town. 87% of the motorists are ready to leave their vehicles the days of high urban pollution level. In less of two years the green products credibility is worsening. Nevertheless the consumer believes sensitive to the ecological arguments. Finally the French are very favorable to the domestic wastes control. (A.L.B.)

  5. The research for a method for controlling atmospheric pollution in a plutonium treatment cell; Recherche d'une methode de controle de la pollution atmospherique dans une cellule traitant le polonium

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    The aerosols likely to contain {sup 210}Po are trapped by bubbling through an acid solution. The problem of determining the polonium concentration of the solution has been solved by combining it with telluric acid. The reduction is carried out at pH = 0 using a solution of stannous chloride. We have studied the factors influencing coprecipitation; nature of the medium, pH, amounts of telluric acid and of stannous chloride. The average yield for the precipitation is 93 per cent. After precipitation, the polonium is filtered on paper and its activity is measured by means of a scintillation counter. The method makes it possible to measure 1/20 of the maximum permissible dose with an accuracy of 20 per cent. (author) [French] Les aerosols susceptibles de contenir du {sup 210}Po sont captes par barbotage dans une solution acide. Le probleme de la concentration de la solution en polonium a ete resolu en entrainant celui-ci avec de l'acide tellurique. La reduction est effectuee a pH = 0 par une solution de chlorure stanneux. Nous avons etudie les facteurs influencant la coprecipitation: nature du milieu, pH, quantite d'entraineur, quantite de chlorure stanneux. Le rendement moyen de la precipitation est de 93 pour cent. Apres precipitation, le polonium est filtre sur papier et son activite mesuree au compteur a scintillations. La methode permet de mesurer le 1/20 de la dose maximum permise avec une precision de 20 pour cent. (auteur)

  6. Heat wave during the summer 2003: relationship between temperature, air pollution and mortality in nine French towns; Vague de chaleur de l'ete 2003: relations entre temperatures, pollution atmospherique et mortalite dans neuf villes francaises

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    The objective of this study is to estimate, by taking the a particular period of summer 2003, the relationship between the exposure to ozone and the mortality risk. This estimation has for aim to realize a more valid, scientifically, evaluation of sanitary impact, for the period of heat wave that this one that could has been lead from anterior results. This study searches also to estimate, for the period of heat wave, the excess of mortality risk linked with the exposure to temperature and air pollution and the relative part of each of these factors in this combined effect. The analysis searches to evaluate an eventual displacement of mortality at short term that is to say a period of under mortality occurring at the immediate declining of the heat wave. (N.C.)

  7. Study and management of atmospheric exhaust gas in acetic acid fermentation developing a new process for alcohol vinegar production; Etude et maitrise des rejets atmospheriques en vinaigrerie, developpement d'un procede nouveau de conduite de la fermentation acetique

    Energy Technology Data Exchange (ETDEWEB)

    Pochat Bohatier, C.

    1999-12-06

    The aim of the study was to examine emissions of volatile organic compounds (VOCs) during acetic (acid) fermentation. The first part of the study presents the methodology developed to reproduce production cycles for spirit vinegar and to analyse gas effluents. The second part describes the origin and quantification of the emissions (ethanol, acetic acid, acetaldehyde and ethyl acetate). The acetic acid is produced by bacterial metabolism while the ethyl acetate is a result of the chemical reaction of esterification. By modelling the emissions during batch processing we were able to identify the various parameters involved when VOCs are carried along by the fermentation gases. The quantities of ethyl acetate depend on the length of time the diluted alcohol is stored, and on its composition. By using a fed-batch method with a continuous supply of ethanol we could reduce alcohol emissions. The third part of the study develops the kinetics studies carried out to adapt the fed-batch process to acetic acid fermentation. The influence of ethanol, either in terms of deficiency or inhibition, is minimized between 8 and 16 g.1-1. A study of the growth rate of bacteria in relation to the amount of acetic acid showed that the latter was highly inhibitive. There is a critical concentration of acetic acid at which the growth of bacteria stops, and the death rate of the culture increases rapidly. The latter depends on the composition of the culture's medium; the corresponding pH of the concentration is between 2.25 and 2.28. By limiting the formation of ethyl acetate in the diluted alcohol and by controlling the concentration of ethanol at 16 g.l -1 per fermentation, the VOC emissions are reduced by 30% and the yield increases as a result. (author)

  8. Effects of air pollution from cars on police health in Paris; Effets de la pollution atmospherique d`origine automobile sur la sante des policiers affectes a la circulation a Paris

    Energy Technology Data Exchange (ETDEWEB)

    Bugajny, Ch.; Delaunay, C.; Viellard, H. [Prefecture de Police de Paris, 75 (France). Laboratoire Central; Petit-Coviaux, F.; Coiron, C.; Squinazi, F. [Laboratoire d`Ygiene de la Ville de Paris, 75 (France); Lecomte, D. [Prefecture de Police de Paris, 75 (France). Dirt. Prevention des Risques Sanitaires

    1999-01-01

    The aim of this study was to assess the effects of car pollution on police health in Paris, more particularly for policemen who are working near streets and crossroads. A population of non-exposed policemen has also been studied as a reference. This work included individual exposure measurements to some urban pollution main indicators and biological determinations to estimate the effects of these pollutants on health. Biological measurements in blood, including determinations of carboxyhemoglobin and lead, were realized on 204 men and women employed by the Prefecture de Police. Carbon monoxide and benzene individual exposure had been measured on 38 men among these policemen, by the use of individual analyzers or pump sampling. Three classes of exposure, which depends on police activities, could be characterized according to CO and benzene exposure levels and carboxyhemoglobin concentrations. Carboxyhemoglobin mean values before traffic exposure are four to five times more important for smokers (4.5 % HbCO) than for no-smokers (1.0 % HbCO). After work, these mean values are respectively 5.3 % and 1.1 % HbCO). We could conclude that no-smokers agents don`t reach the WHO value (2.5 % HbCO), which should not been exceeded, while average HbCO percentage for smokers after work is twice more important than OMS value. So, smoking contributes to higher levels of CO in blood than car exhaust pollutants, even for high air pollutants concentrations. CO exposure levels are lower than the WHO recommendations for all the durations, and therefore lower than limit values fixed in working places (55 mg.m{sup 3} for 8 hours). No level for airborne benzene is recommended by WHO, as this compound is carcinogenic to humans; WHO indicated that for an air concentration of 1 {mu}g.m{sup 3}, the estimated lifetime risk of leukaemia is 4.10{sup -6}. Individual benzene measurements are lower than limit concentrations for working place (16 mg.m{sup 3} for 8 hours). Lead blood levels, which average value is 45 {mu}g/l, are clearly smaller that the WHO value (200 {mu}g/l), considered for the beginning of a chronical lead poisoning. (authors) 10 refs.

  9. Veinijutud Torresega / Kertu Lukas

    Index Scriptorium Estoniae

    Lukas, Kertu, 1980-

    2005-01-01

    Oktoobri keskel käis kuulsa Torrese veiniperekonna marketingijuhist perepoeg Miguel Torres Jr Eestis, et tutvustada siinsetele veinisõpradele esimest Torrese Ribera del Duero piirkonna veini - Celeste Tempranillo 2003

  10. Fulltext PDF

    Indian Academy of Sciences (India)

    such an effect, because the plane of the moon's orbit turns once in about eighteen ... Dividing by zero is bad. Dividing ... instituted for the best solution 3. Poincare's ... Nouvelles de la Mecanique Celeste' (New methods of Celestial. Mechanics) ...

  11. High resolution and high precision absorption spectroscopy using high finesse cavities: application to the study of molecules with atmospheric interest; Cavites de haute finesse pour la spectroscopie d'absorption haute sensibilite et haute precision: application a l'etude de molecules d'interet atmospherique

    Energy Technology Data Exchange (ETDEWEB)

    Motto-Ros, V.

    2005-12-15

    High finesse cavities are used to measure very weak absorption features. Two different methodologies are investigated and applied to the study of molecules with atmospheric interest. First, Continuous Wave - Cavity Ring Down Spectroscopy (CW-CRDS) is used to study the atmospheric spectra of water vapour in the near infrared range. These measurements are performed for temperature and pressure of atmospheric relevance for DIAL applications (Differential Absorption Lidar). This study, financed by the European Space Agency (ESA), goes with the WALES mission (Water Vapour Lidar Experiment in Space). The experimental setup was conceived in order to control pressure, temperature and relative humidity conditions. A particular attention is done to characterize and describe the spectrometer. Then, measurements of red Oxygen B band are performed to demonstrate the huge performance of Optical Feedback Cavity Enhanced Absorption Spectroscopy (OF-CEAS). The desired optical feedback is obtained by light injection into the high finesse cavity through a glass plate placed inside the cavity and closed to the Brewster angle. We show a measurement dynamical range of 5 orders of magnitude (10{sup -5} to 10{sup -10} /cm) and a sensitivity of 10{sup -10} /cm/{radical} Hz. Also, sampling absorption spectra by the super linear cavity frequency comb allows very precise frequency measurements. This is demonstrated by the determination of Oxygen pressure shifts with an absolute accuracy of around 5 x 10{sup -5} cm{sup -1}/atm. To our knowledge, we provide the highest accuracy ever reported for this parameter. (author)

  12. Study of the carbonaceous fraction of the atmospheric aerosol in Chamonix and St Jean de Maurienne: seasonal evolutions, source and chemical characteristics; Etude de la fraction carbonee de l'aerosol atmospherique a Chamonix et St Jean de Maurienne: evolutions saisonnieres, sources et caracteristiques chimiques

    Energy Technology Data Exchange (ETDEWEB)

    Aymoz, G

    2005-03-15

    The atmospheric aerosols play an important role in the earth climatic system. They are also at the origin of air pollution problems in urban areas. However, their influence on the global climactic change, as well as their chemical properties in urban zone, is still very poorly known. One of the main reasons to that is the lack of information on one of the major components of aerosol, the carbonaceous matter. This work focuses on a better knowledge of this particulate carbonaceous matter. This study presents measurements of carbonaceous matter (OC and EC) in aerosol (PM10) performed within the framework of the program POVA, between February 2001 and June 2003 in Chamonix and St Jean de Maurienne (French Alps). This series represents one of the first of this type for basic sites of alpine valleys, characterized by emissions located in the bottom of the valleys and strong temperature inversions in winter, limiting the dispersion of pollutants. The POVA program, centred on the study of air pollution in these valleys, was proposed following the closing of the 'Tunnel du Mont Blanc', in 1999. One of the main objectives was to evaluate the sources of pollution by particles, in particular the share due to the international heavy duty traffic. We could establish that, on the two sites and while the international heavy duty traffic was not restored in the Chamonix Valley, this source represented approximately a third of the observed mass of particles, and was at the origin of a weaker fraction of the carbonaceous matter mass. The extremely primary character of the carbonaceous matter is a remarkable specificity of our sites. The source of carbonaceous matter represented by light vehicles emissions could not be studied. Then, it appears that combustion of biomass (probably from fireplaces) plays an important role, increased in the case of low temperatures, on the levels of pollution by particles. Lastly, the potential impact of the semi-volatile matter condensation at the low temperatures remains an assumption to be tested. On a more general point of view, several results can be pointed out concerning the organic matter: 1. The conversion factor of organic carbon mass to organic matter mass is undoubtedly very variable for a given site (in particular, its variability is probably largely higher than 0,2). 2. The generally allowed assumptions for the calculation of the secondary fraction of OC appeared false in the case of our study, and the method seems in the general case very dubious. 3. The soluble fraction of OC is very important on our sites. The primary source of biomass combustions is an important primary source of WSOC. This result is in disagreement with the general assumption that WSOC is mostly with a secondary origin. (author)

  13. Presentation of the health impact evaluation study of atmospheric emissions of a major coal combustion installation; Mise a jour de l'etude d'evaluation de l'impact sur la sante des rejets atmospheriques des tranches charbon d'une grande installation de combustion

    Energy Technology Data Exchange (ETDEWEB)

    Bonnard, R

    2004-12-15

    In the framework of a working group on the major installations, a study has been realized on a today coal combustion installation. The direct risk by inhalation and the risks bond to indirect exposure of atmospheric releases were analyzed. The calculation method is explained and the uncertainties are discussed to present the results. (A.L.B.)

  14. Short term effect of urban air pollution on respiratory disease, especially chronic obstructive pulmonary disease (COPD). Analysis of studies published from 1962 to january 2000; Impact a court terme de la pollution atmospherique urbaine sur l'insuffisance respiratoire par bronchopneumopathie chronique obstructive (BPCO). Synthese des etudes, publiees de 1962 a janvier 2000

    Energy Technology Data Exchange (ETDEWEB)

    Desqueyroux, H.; Momas, I. [Universite Rene Descartes, Faculte des Sciences Pharmaceutiques et Biologiques, Lab. d' Hygiene et de Sante Publique, 75 - Paris (France)

    2001-02-01

    This review presents a synthesis of studies published from 1962 to 2000 on the relations between air pollution and chronic obstructive pulmonary disease (COPD): 12 ecological epidemiological studies, 6 epidemiological panel studies, and 11 controlled human exposure trials. The controlled trials, ecological time-based epidemiological studies and panels are examined successively followed by a discussion of their methodology and results. The controlled trials either do no highlight effects or show effects having no clinical significance since variations are similar to physiological variability. For epidemiological studies reporting individual data, the results point to a particle effect (two studies). This effect of particles is found in ecological studies which also describe an impact of ozone, sometimes of sulfur dioxide and less often of nitrogen dioxide. In conclusion, patients suffering from COPD are generally regarded as a group sensitive to air pollution, as suggested by the results of numerous ecological epidemiological studies. Rare individual studies provide a few arguments supporting this assumption. (authors)

  15. Programme of air surveillance and health 9 towns. Synthesis review. Surveillance of effects on the health in relation with air pollution in urban area. Phase 2; Programme de surveillance Air et Sante 9 villes. Revue de synthese. Surveillance des effets sur la sante lies a la pollution atmospherique en milieu urbain. Phase 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-06-15

    The InVS published its first results on the Nine-City Air and Health Surveillance Programme (PSAS-9) in March 1999. This phase I pointed out that it was possible for various specialists in the field of air pollution and health to gather around a common set of problems. They also found a link between the daily variations of all the urban air pollution indicators and the total, cardio-vascular and respiratory mortality which, based on French data, contributed to strengthen scientific knowledge in this field. Today's report presents the results of phase Il of the PSAS-9 programme which essentially aimed at assessing the short-term exposure-risk relationships between pollution indicators and hospital admission indicators. This second phase also allowed to confirm the results of phase I on the short-term effect of air pollution on mortality thanks to longer periods of study. Exploratory analysis using new indicators and sensitivity analysis on the pertinence of results were also conducted. Finally, methodological tools were developed in order to optimise data collection and statistical modelization. All these results enabled the quantification of the short-term health impact of air pollution on the PSAS-9 cities. PSAS-9 is now an ongoing epidemiological surveillance programme on the effects of urban air pollution on health, providing information tools to decision-makers and the general population. (author)

  16. Application of the 'CORINAIR' method for the estimation of atmospheric pollution due to the Park ONE thermal power plants in Morocco; Application de la methode 'CORINAIR' pour l'evaluation de la pollution atmospherique due au centrales thermiques du parc ONE du Maroc

    Energy Technology Data Exchange (ETDEWEB)

    Benzha, F.; Tahiri, M.; Souabi, S.; Darif, A.; Khatami, A. [University of Hassan 2, Mohammadia (Morocco)

    2009-07-01

    Burning oil, gas, coal and pet coke are the main source of gaseous and particulate emissions. In Morocco, the production of electricity is largely dependent on fossil fuels that are highly polluting. In this work the authors assess the impact of these pollutants on the environment, a study which aims to know the emission levels from the power stations of the National Office of Electricity (ONE) in Morocco.

  17. Bulky PAH-DNA induced by exposure of a co-culture model of human alveolar macrophages and embryonic epithelial cells to atmospheric particulate pollution; Adduits encombrants a l'ADN dans des cocultures de cellules pulmonaires humaines exposees a une pollution atmospherique particulaire

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, Imane; Garcon, Guillaume; Billet, Sylvain; Shirali, Pirouz [Universite Lille Nord de France - Lille (France); Unite de Chimie Environnementale et Interactions sur le Vivant, MREI, Universite du Littoral Cote d' Opale, Dunkerque (France); Andre, Veronique; Le Goff, Jeremie; Sichel, Francois [GRECAN, Universite de Caen Basse-Normandie et centre Francois Baclesse, Caen (France); Roy Saint-Georges, Francoise; Mulliez, Philippe [Service de Pneumologie, Hopital Saint-Philibert, GHICL, Lille (France)

    2012-01-15

    Because of their deep penetration in human lungs, fine airborne particulate matter were described as mainly responsible for the deleterious effects of exposure to air pollution on health. Organic constituents are adsorbed on particles surface and, after inhalation, some (polycyclic aromatic hydrocarbons, PAHs) can be activated into reactive metabolites and can bind to DNA. The formation of bulky DNA adducts has been researched after exposure of mono-and co-cultures of alveolar macrophages (AM) and human embryonic human lung epithelial (L132), to fine air pollution particulate matter Air samples have been collected with cascade impactor and characterized: size distribution (92.15% < 2.5{mu}.m), specific surface area (1 m{sup 2}/g), inorganic (Fe, AI, Ca, Na, K, Mg, Pb, etc.) and organic compounds (PAHs, etc.). {sup 32}P post-labeling method was applied to detect bulky DNA adducts in AM and L132, in mono-and co-cultures, 72 h after their exposure to atmospheric particles at their Lethals and Effects concentrations or (LC or CE) to 50% (i.e. MA: EC{sub 50} = 74.63 {mu}g/mL and L132: LC-5-0 = 75.36 {mu}g/mL). Exposure to desorbed particles (MA: C1= 61.11 {mu}g/mL and L132 : C2 = 61.71 {mu}g/mL) and B[a]P (1 {mu}M) were included. Bulky PAH-DNA adducts were detected in AM in mono-culture after exposure to total particles (Pt), to B[a]P and desorbed particles (Pd). Whatever the exposure, no DNA adduct was detected in L132 in mono-culture. These results are coherent with the enzymatic activities of cytochrome P450 l Al in AM and L132. Exposure of co-culture to Pt, or Pd induced bulky adducts to DNA in AM but not in L132. Exposure to B[a]P alone has altered the DNA of AM and L132, in co-culture. Exposure to Pt is closer to the environmental conditions, but conferred an exposure to amounts of genotoxic agents compared to studies using organic extracts. The formation of bulky DNA adducts was nevertheless observed in AM exposed to Pt, in mono- or co-culture, indicating that they were competent in terms of metabolic activation of PAHs. The DNA damage in the L132 in co-culture following exposure to B[a]P have suggested that some PAH metabolites generated by the MA could be have a genotoxic action on L132. (authors)

  18. Mutational pattern of TP53 tumor suppressor gene in human lung cells exposed to air pollution PM{sub 2.5}; Spectre mutationnel de TP53 en reponse a une exposition in vitro a un aerosol atmospherique particulaire PM{sub 2,} {sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Billet, Sylvain; Paget, Vincent [Universite Lille Nord de France, Lille (France); Unite de Chimie Environnementale et Interactions sur le Vivant, Maison de la Recherche en Environnement Industriel, Universite du Littoral Cote d' Opale, Dunkerque (France); GRECAN, Universite de Caen Basse-Normandie et Centre Regional de Lutte Contre le Cancer Francois Baclesse, Caen (France); Garcon, Guillaume; Verdin, Anthony; Shirali, Pirouz [Universite Lille Nord de France, Lille (France); Unite de Chimie Environnementale et Interactions sur le Vivant, Maison de la Recherche en Environnement Industriel, Universite du Littoral Cote d' Opale, Dunkerque (France); Andre, Veronique; Heutte, Natacha; Sichel, Francois [GRECAN, Universite de Caen Basse-Normandie et Centre Regional de Lutte Contre le Cancer Francois Baclesse, Caen (France)

    2012-01-15

    Environmental exposure to fine airborne particulate matter (PM 2.5) is thought to be responsible for cardiopulmonary diseases, including lung cancer. However, the mechanisms of action potentially involved in PM{sub 2.5} toxicity are not yet fully described. Mutations in the TP53 gene are the most common alterations in human solid tumors. TP53 mutational patterns have sometimes been linked to carcinogen exposure. The purpose of this study was to determine the mutations that alter the functionality of this transcription factor in a model of human epithelial lung cells (A549) exposed to the fine particulate fraction (PM{sub 2.5}) of an atmospheric aerosol sampled under urban and industrial influences. PM{sub 2.5} was collected in Dunkerque City by cascade impaction. Its physicochemical characterization revealed the presence of many inorganic and organic compounds, including some that are known for their toxicity. The search for mutations altering the functionality of the P53 protein was performed 72 h after exposure of A549 cells to PM{sub 2.5} at its lethal concentration at 50% (LC{sub 50}, 118.60 {mu}g/mL = 31.63 {mu}g/cm{sup 2}), using the Functional Analysis of Separated Alleles in Yeast (FASAY). Sixteen mutations altering P53 function were detected after A549 cells exposure to the collected PM{sub 2.5}: eight deletions of one or two nucleotides and eight nucleotide substitutions, mainly transitions A > G and G > A. These mutations are described in the literature as possibly caused by endogenous mechanisms, such as oxidative stress. This kind of alteration can be induced by metal content of the PM{sub 2.5}, as well as by metabolic activation of the organic compounds coated onto its surface. Involvement of oxidative stress in TP53 mutations was confirmed by the detection of an oxidative DNA adduct, 8-hydroxy-2'-deoxyguanosine (8-OHdG), in A549 cells exposed to the collected PM. (authors)

  19. Determination of some fundamental characteristics of Geiger-Mueller counters. Applications to the study of delayed particles from cosmic-ray shower; Sur la determination de quelques caracteristiques fondamentales de compteurs de geiger-muller applications a l'etude des particules retardees des gerbes atmospheriques du rayonnement cosmique

    Energy Technology Data Exchange (ETDEWEB)

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

    1954-06-15

    After some historic recalls, the different phases of discharge of a Geiger-Mueller counter is studied. It measures, by oscillograph method, the time between the flow of a particle through a determined area of the counter and the response of the associated amplifier. This time length is composed by the latency period and the delay itself which depends on the amplifier sensitivity. The selection of particles which generate a discharge in the studied counter is obtained with a two coincidence counters telescope in which the aperture is limited by four counters in anticoincidence with the first two counters. The measures have been done with different distance values and an overvoltage V{sub s} which was applied to the counter. The dead time of a GM counter is also measured with a delayed coincidences method. The counter pulses which supply the coincidence circuit are delivered directly or with a known and variable delay. This method allows also to study the spurious pulses which are due to the positive ions impact on the counter cathode. Results for counters working in different conditions are given. It describes the system to limit the discharge which induces the increase of the life working of a counter, the decrease of its dead time and the reduction of the number of spurious pulses. In a second part, it describes the system to study the time correlation between different particles of the cosmic ray. An experiment concerning the presence of delayed particles in cosmic showers has permitted to specify the superior limit of this phenomena which is directly connected to the presence of heavy nuclear particles in the cosmic shower. (M.P.)

  20. Evaluation of sanitary impact of the urban air pollution. Agglomeration of Angouleme, Niort and Poitiers impact at short and long term; Evaluation de l'impact sanitaire de la pollution atmospherique urbaine. Agglomeration d'Angouleme, Niort et Poitiers impact a cour et long terme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    An health impact assessment of air pollution based on the I.n.V.S. guidelines has been conducted in Angouleme, Niort and Poitiers according to the Regional Plan for the quality of air in the region of Poitou- Charentes. Short-term effects on morbidity (hospital admissions in 2001 and 2002) and mortality were estimated. Long-term effects due to air pollution on mortality were also evaluated. The estimated numbers of hospitalizations for cardiovascular and respiratory admissions due to air pollution are 19 in Angouleme, 11 in Niort and 19 in Poitiers. For long-term mortality the estimated impact is 25 in Angouleme, 19 in Niort and 23 in Poitiers. The different scenarios of air pollution reduction showed that the most effective ones are those which lead to reduce of 25% the mean of the involved pollutant. Results showed that air pollution are even resulting in health effects for some levels of pollution lower than current limits. The most effective actions should therefore associate reduction of the source emissions on a daily basis and decrease of the over-limits levels of pollution. (author)

  1. Evaluation of sanitary impact of urban air pollution. Agglomeration of Orleans and Tours impact at short and long term; Evaluation de l'impact sanitaire de la pollution atmospherique urbaine. Agglomeration d'Orleans et de Tours impact a cour et long terme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    An health impact assessment of air pollution based on the I.n.V.S. guidelines has been conducted in Orleans and Tours according to the regional Plan for the quality of air in the region of Centre. Short-term effects on morbidity (hospital admissions in 2002 and 2003) and mortality. Long-term mortality was also estimated. The estimated numbers of hospitalizations are: Orleans: 11 [2-23]* for respiratory admissions and 26 [16-36]* for cardiovascular admissions; Tours: 11 [3-22]* for respiratory admissions and 34 [20-48]* for cardiovascular admissions. For long-term mortality the estimated impact is 59 [36-84]* in Orleans and 61 [37-86]* in Tours. The different scenarios of air pollution reduction showed that the most effective ones are those which lead to reduce of 25% the mean of the involved pollutant. Results showed that air pollution are even resulting in health effects for some levels of pollution than current limits. The most effective actions should therefore associate reduction of the source emissions on a daily basis and decrease of the over-limits levels of pollution. (author)

  2. Situation of regional plans for air quality. Acknowledgement of sanitary aspects. Situation of realised impact studies of urban air pollution; Bilan des plans regionaux pour la qualite de l'air. Prise en compte des aspects sanitaires. Bilan des etudes d'impact de la pollution atmospherique urbaine realisees

    Energy Technology Data Exchange (ETDEWEB)

    D' Helf, M.; Cassadou, S

    2005-07-01

    The law on air and use of energy recommended in 1996 the implementation of regional plans for air quality (P.Q.R.A.) that have to rely on an evaluation of air pollution effects on health. 21 P.Q.R.A. have been published and the report gives the situation, their sanitary orientations and their applications. An inquiry lead in the 21 regions, near the different regional actors in the air and health field completes the report. (N.C.)

  3. Considering the sanitary aspects in regional plans for air quality. Situation of sanitary impacts of urban air pollution studies; Prise en compte des aspects sanitaires dans les Plans regionaux pour la qualite de l'air. Bilan des etudes d'impact sanitaires de la pollution atmospherique urbaine realisees

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-12-15

    The law on air and the rational use of energy of the 30. september 1996 forecasts the setting up of regional planning for the air quality that have to rely on the support of an evaluation of sanitary effects of air pollution. To help the local sanitary authorities in this mission, the National Institute of Sanitary Surveillance and the C.I.R.E. have realised a methodological guide on evaluation of sanitary impact of urban air pollution in different contexts. (N.C.)

  4. Indoor air pollution: measurement campaign in six dwellings occupied by elderly. Relation between indoor air quality and declared symptoms; Pollution atmospherique interieure: campagne de mesures dans six logements occupes par des personnes agees, relation entre qualite de l'air et symptomes declares

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, C.

    2004-10-15

    The objective of this work was to analyse the indoor air quality in dwellings occupied by old people and to correlate pollutants with life habits and health statement. A sociological survey on 96 elderly people living in social housing was firstly undertaken in order to determine risk factors responsible for poor health. Then measurements of several pollutants (CO{sub 2}, CO, NO{sub X}, O{sub 3}, COVT, PM2,5, PS>0,3 and aero-biological counts) were carried out during five days in six typical dwellings. Results were analyzed in the light of activities and reported symptoms by the old people. Besides discomfort due to CO{sub 2} accumulation, several pollutants with levels near or over guidelines were identified in particular particulate matter under 1 {mu}m, airborne microbiological counts, permanent TVOC levels. Dust was at the origin of cough, eyes and throat irritations and flows of the nose, and fungi and bacteria seem to be responsible for skin irritations, digestive disorders, sneezes and rhinitis. However, most symptoms appeared after 10 hours of exposure time for people of all ages. The risks factors were amplified by ignorance about the hazard of inadequate ventilation. Experiences in laboratory were also performed to complement some observations and introduce further research. (author)

  5. Is acidification still a major air pollution concern? The analysis from the French Agriculture and Fishing Department; Le probleme de l`acidification d`origine atmospherique est-il toujours d`actualite? l`analyse du Ministere de l`agriculture et de la peche

    Energy Technology Data Exchange (ETDEWEB)

    Landmann, G. [Ministere de l`Agriculture et de la Peche, 75 - Paris (France). Direction de l`espace rural et de la foret

    1997-12-31

    The acidification issues related to agriculture and their effects on ecosystems are analyzed: through ammonium emissions, agriculture is largely contributing to acidification and eutrophication of ecosystems; enhancements of cultivation and fertilization techniques have been achieved in order to decrease these emissions; natural soils and waters, and more especially forests, are still affected by acid and nitrogenous pollution, leading to modifications with soil degradation and eutrophication of forest soils and waters

  6. Programme of air surveillance Air and Health 9 towns. Surveillance of effects on health in relation with air pollution in urban area. Phase 2; Programme de surveillance Air et Sante 9 villes. Surveillance des effets sur la sante lies a la pollution atmospherique en milieu urbain. Phase 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-06-15

    The InVS published its first results on the Nine-City Air and Health Surveillance Programme (PSAS-9) in March 1999. This phase I pointed out that it was possible for various specialists in the field of air pollution and health to gather around a common set of problems. They also found a link between the daily variations of all the urban air pollution indicators and the total, cardio-vascular and respiratory mortality which, based on French data, contributed to strengthen scientific knowledge in this field. Today's report presents the results of phase Il of the PSAS-9 programme which essentially aimed at assessing the short-term exposure-risk relationships between pollution indicators and hospital admission indicators. This second phase also allowed to confirm the results of phase I on the short-term effect of air pollution on mortality thanks to longer periods of study. Exploratory analysis using new indicators and sensitivity analysis on the pertinence of results were also conducted. Finally, methodological tools were developed in order to optimise data collection and statistical modelization. All these results enabled the quantification of the short-term health impact of air pollution on the PSAS-9 cities. PSAS-9 is now an ongoing epidemiological surveillance programme on the effects of urban air pollution on health, providing information tools to decision-makers and the general population. (author)

  7. Study of atmospheric photo-oxidation mechanisms by concentration measurements of peroxy radicals by chemical amplification in the laboratory and in the atmosphere; Etudes des mecanismes de photooxydation atmospherique par mesure des radicaux peroxyles par amplification chimique au laboratoire et dans l'atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Pinceloup, St.

    2002-10-01

    In this thesis, we have continued to develop and to automate a chemical amplifier, with which measurements of peroxy radicals (RO{sub 2}) under real and simulated atmosphere can be made in order to better understand the atmospheric oxidation processes. Firstly, some experiments in laboratory have confirmed the inhibitory effect of water vapour on the chain length of the chemical amplifier, which is a technique of measuring peroxy radicals used by the LCSR. We have shown that the decrease in the chain length is primarily due to the increase of the HO{sub 2} loss to the wall of the amplifier in presence of H2{sub O} and to the HO{sub 2} loss in the gas phase by a minority way of the reaction NO + HO{sub 2} producing HNO{sub 3}. This reaction was studied using a turbulent flow reactor coupled to an ion molecule reactor with mass spectrometric detection. Secondly, the photo-oxidation of formaldehyde has been studied in the atmospheric simulation chamber of the LISA at Creteil coupled with the chemical amplifier. This study has allowed us to determine realistic values of the photolysis constants of radical and molecular ways of formaldehyde and the thermal decomposition constant at 298 K of the adduct HOCH{sub 2}O{sub 2} formed by reaction of HO{sub 2} with HCHO, thanks to the peroxy radicals measurements effectuated. Finally, we have participated in the field campaign, ESCOMPTE, during which concentrations of RO{sub 2}, NO, NO{sub 2} and ozone were measured continuously at the Dupail site. The measured concentrations were typical of a rural site. Using these measurements and those accomplished by other teams, we have determined the production rate of ozone by the radical budget method. The results show that the local photochemical production was important on the Dupail site and controlled essentially by the nitrogen oxides (NO, NO{sub 2}) characterizing a site free of emissions. (author)

  8. Study of the carbonaceous fraction of the atmospheric aerosol in Chamonix and St Jean de Maurienne: seasonal evolutions, source and chemical characteristics; Etude de la fraction carbonee de l'aerosol atmospherique a Chamonix et St Jean de Maurienne: evolutions saisonnieres, sources et caracteristiques chimiques

    Energy Technology Data Exchange (ETDEWEB)

    Aymoz, G.

    2005-03-15

    The atmospheric aerosols play an important role in the earth climatic system. They are also at the origin of air pollution problems in urban areas. However, their influence on the global climactic change, as well as their chemical properties in urban zone, is still very poorly known. One of the main reasons to that is the lack of information on one of the major components of aerosol, the carbonaceous matter. This work focuses on a better knowledge of this particulate carbonaceous matter. This study presents measurements of carbonaceous matter (OC and EC) in aerosol (PM10) performed within the framework of the program POVA, between February 2001 and June 2003 in Chamonix and St Jean de Maurienne (French Alps). This series represents one of the first of this type for basic sites of alpine valleys, characterized by emissions located in the bottom of the valleys and strong temperature inversions in winter, limiting the dispersion of pollutants. The POVA program, centred on the study of air pollution in these valleys, was proposed following the closing of the 'Tunnel du Mont Blanc', in 1999. One of the main objectives was to evaluate the sources of pollution by particles, in particular the share due to the international heavy duty traffic. We could establish that, on the two sites and while the international heavy duty traffic was not restored in the Chamonix Valley, this source represented approximately a third of the observed mass of particles, and was at the origin of a weaker fraction of the carbonaceous matter mass. The extremely primary character of the carbonaceous matter is a remarkable specificity of our sites. The source of carbonaceous matter represented by light vehicles emissions could not be studied. Then, it appears that combustion of biomass (probably from fireplaces) plays an important role, increased in the case of low temperatures, on the levels of pollution by particles. Lastly, the potential impact of the semi-volatile matter condensation at the low temperatures remains an assumption to be tested. On a more general point of view, several results can be pointed out concerning the organic matter: 1. The conversion factor of organic carbon mass to organic matter mass is undoubtedly very variable for a given site (in particular, its variability is probably largely higher than 0,2). 2. The generally allowed assumptions for the calculation of the secondary fraction of OC appeared false in the case of our study, and the method seems in the general case very dubious. 3. The soluble fraction of OC is very important on our sites. The primary source of biomass combustions is an important primary source of WSOC. This result is in disagreement with the general assumption that WSOC is mostly with a secondary origin. (author)

  9. Contributions of the CEA-Valduc Centre control to the understanding of the transfers of atmospheric tritiated water into the different parts of the environment; Apports de la surveillance du Centre CEA-Valduc sur la connaissance des transferts de l'eau tritiee atmospherique dans les differents compartiments de l'environnement

    Energy Technology Data Exchange (ETDEWEB)

    Guetat, P.; Vichot, L. [CEA Valduc, UMR, 21 - Is-sur-Tille (France); Tognelli, A. [CEA Bruyeres-le-Chatel, 91 (France)

    2009-07-01

    After a description of the geological environment of the Valduc Centre dedicated to tritium purification and tritiated waste processing and storage, this document presents the assessment of quantities of tritiated water released by the Valduc Centre and of their evolution in the hydro-geological environment. It provides in situ macroscopically observed data on the transfer mechanisms of water into the different parts of the environment and into the food chain by means. This is made possible by the exceptional traceability of tritiated water. Finally, a comparison between computational models and experimental measurements is given

  10. Atmospheric pollution and heating plants in urban area. What technical solutions for the coal and the heavy oil? For which costs?; Pollution atmospherique et chaufferies en milieu urbain. Quelles solutions techniques pour le charbon et le fioul lourd?. A quel couts?

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    In France, furnaces fed with coal and heavy fuel and established in urban area, are bound by many restraints: a reinforcement of the regulations on atmospheric emissions, a strong social demand bound to the urban air quality improvement and a necessary costs mastership. So buildings managers and persons responsible for district heating are confronted with technical and strategical choices. To answer their questions ADEME organized a day of information around four main themes: the urban heating in France, actions on fuels, possible technics for the smokes desulfurization and nitrogen oxides reduction, costs and financing of the solutions. (A.L.B.)

  11. Association between ambient carbon monoxide levels and hospitalizations for congestive heart failure in the elderly in 10 canadian cities; Association entre les niveaux atmospheriques de monoxyde de carbone et les hospitalisations pour insuffisance cardiaque congestive des personnes agees dans 10 villes canadiennes

    Energy Technology Data Exchange (ETDEWEB)

    Burnett, R.T.; Dales, R.E.; Brook, J.R.; Raizenne, M.E.; Krewski, D.

    2001-01-01

    In 1995, two studies, realized in the USA, showed the relation between the carbon monoxide content in the urban air and the hospitalization of elderly people for congestive heart failure. This study, realized this time in the Canada, take again the protocol of one of them increasing the period (4 to 11 years) and the number of concerned towns. (A.L.B.)

  12. High resolution and high precision absorption spectroscopy using high finesse cavities: application to the study of molecules with atmospheric interest; Cavites de haute finesse pour la spectroscopie d'absorption haute sensibilite et haute precision: application a l'etude de molecules d'interet atmospherique

    Energy Technology Data Exchange (ETDEWEB)

    Motto-Ros, V

    2005-12-15

    High finesse cavities are used to measure very weak absorption features. Two different methodologies are investigated and applied to the study of molecules with atmospheric interest. First, Continuous Wave - Cavity Ring Down Spectroscopy (CW-CRDS) is used to study the atmospheric spectra of water vapour in the near infrared range. These measurements are performed for temperature and pressure of atmospheric relevance for DIAL applications (Differential Absorption Lidar). This study, financed by the European Space Agency (ESA), goes with the WALES mission (Water Vapour Lidar Experiment in Space). The experimental setup was conceived in order to control pressure, temperature and relative humidity conditions. A particular attention is done to characterize and describe the spectrometer. Then, measurements of red Oxygen B band are performed to demonstrate the huge performance of Optical Feedback Cavity Enhanced Absorption Spectroscopy (OF-CEAS). The desired optical feedback is obtained by light injection into the high finesse cavity through a glass plate placed inside the cavity and closed to the Brewster angle. We show a measurement dynamical range of 5 orders of magnitude (10{sup -5} to 10{sup -10} /cm) and a sensitivity of 10{sup -10} /cm/{radical} Hz. Also, sampling absorption spectra by the super linear cavity frequency comb allows very precise frequency measurements. This is demonstrated by the determination of Oxygen pressure shifts with an absolute accuracy of around 5 x 10{sup -5} cm{sup -1}/atm. To our knowledge, we provide the highest accuracy ever reported for this parameter. (author)

  13. Inventory of atmospheric pollutant and greenhouse gas emissions in France. Sectoral series and extended analyses - SECTEN Format, April 2011; Inventaire des emissions de polluants atmospheriques et de gaz a effet de serre en France. Series sectorielles et analyses etendues - Format SECTEN, avril 2011

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jean-Pierre; Fontelle, Jean-Pierre; Serveau, Laetitia; Allemand, Nadine; Jeannot, Coralie; Andre, Jean-Marc; Joya, Romain; Deflorenne, Emmanuel; Martinet, Yann; Druart, Ariane; Mathias, Etienne; Gavel, Antoine; Nicco, Laetitia; Gueguen, Celine; Prouteau, Emilie; Jabot, Julien; Tuddenham, Mark; Jacquier, Guillaume; Vincent, Julien

    2011-04-15

    This report supplies an update of emissions into the atmosphere in mainland France under the SNIEPA in accordance with the 'SECTEN' format defined by CITEPA. This report aims to reconstitute emissions broken down in accordance with the traditional economic sectors such as industry, residential/tertiary sector, agriculture, etc. (cf. Annex 2 for the corresponding links between SECTEN sectors and sub-sectors, and the SNAP nomenclature). Unless otherwise indicated, the results cover the period 1990-2010 (estimations for 2010 are preliminary), but also go back further in time: to 1980 for certain substances covered by the different protocols adopted under the 1979 UNECE Convention on Long-Range Transboundary Air Pollution. For other substances traditionally monitored by CITEPA for many years, the results go back to 1960 (SO{sub 2}, NO{sub x}, CO{sub 2}, CO). Data are presented for 28 different substances in total and various indicators such as those concerning acidification or the greenhouse effect. The report shows that for most substances, emissions have been drastically reduced over the last 10 or 20 years, especially during the period 1990-2009: Very sharp decrease (over 40%) SO{sub 2}, NMVOCs, CO, SF{sub 6}, PFCs in CO{sub 2} equivalent, As, Cd, Cr, Hg, Ni, Pb, Zn, dioxins and furans, PAHs, HCB, PCBs, PM{sub 2.5} and PM{sub 1.0}, Sharp decrease (between 20 and 40%) NO{sub x}, N{sub 2}O, Se, TSP, PM{sub 10} and acid equivalent index, Considerable decrease (between 5 and 20%) NH{sub 3}, CH{sub 4} without LULUCF, CO{sub 2} without LULUCF, Cu and the global warming potential index without LULUCF, Stabilisation (between -5 and +5%) No substance, Very sharp increase (over 40%) HFCs in CO{sub 2} equivalent. For more than 2/3 of substances, emission levels in 2009 were the lowest since records began (1960 to 1990 depending on the substances). For the most part of atmospheric pollutants (except the greenhouse gases), the preliminary estimations for year 2010 look rather favorable as far as the estimated level is below than observed in 2009. Regarding the greenhouse gases, the trend is rather directed in a light increase (2, 2 % between 2009 and 2010 for the CO{sub 2} and 1, 4 % in terms of PRG) because of the year 2009 is very marked by a context of economic crisis and a resumption begun in 2010. The preliminary estimations for year 2010 should therefore be considered with caution because they need to be consolidated. The results are presented at national level for each of the main sectors defined in the SECTEN format. A more detailed breakdown of each main sector is provided for the period 1990-2009. Results also focus on the different energy products and several analyses provide additional information on NMVOCs, PAHs HFCs, PFCs, global warming potential and particular sources, such as transport and off-road mobile sources (generators, machinery and vehicles used in construction, industry, agriculture and forestry, as well as household and gardening machinery). The report contains indications regarding the targets to which France has committed itself under international conventions and EU directives, in particular for climate change and for transboundary air pollution and air quality. These results show that on the whole emission trends observed are encouraging and especially reflect the reduction actions implemented. The table below summarises total emissions over the period 1990-2010 for all the above mentioned substances, as well as indicators concerning acidification and the greenhouse effect

  14. Study of the coastal atmospheric boundary layer during ESCOMPTE 2001. Evaluation and improvement of the efficiency of a UHF radar; Etude de la couche limite atmospherique cotiere durant ESCOMPTE 2001. Evaluation et amelioration des performances d'un radar UHF

    Energy Technology Data Exchange (ETDEWEB)

    Puygrenier, V.

    2005-12-15

    Forecasting of pollution events was the main objective of the ESCOMPTE-2001 campaign, which took place in the Marseille/Fos/Berre heterogeneous area (southeastern France) in the early summer 2001. This goal requires good understanding and taking into account, by physico-chemical numerical models, of the physical processes in the Atmospheric Boundary Layer (ABL), in which pollutants are emitted, transported and diffused. In the ESCOMPTE-2001 campaign context, this work was devoted to study the low troposphere during sea breeze events, related to meteorological conditions responsible for poor air quality of coastal areas. It presents notably an oscillation of the sea breeze intensity and competitions of locals and regional sea breeze, which change the advective time of the marine air above the continental surface and thus influence the ABL development and its pollutants concentration. This study is based principally on the network of four UHF wind profilers radars set up on the coastal area of Marseille/Fos/Berre, allowing a continuous three-dimensional description of the sea breeze flow and the ABL. For the needs of this phenomenological work, methodological developments was realized to improve the measurement of ABL turbulent properties with UHF radars (terms of turbulent kinetic energy budget) and the use of wind profilers network for the study of pollutants plumes trajectory-graphy. (author)

  15. Measurement equipment fitted in light vehicles used for supervision and reconnaissance by the radioprotection service at Cadarache; Equipement de mesures des vehicules legers de surveillance et de reconnaissance de la S. P. R. Cadarache

    Energy Technology Data Exchange (ETDEWEB)

    Galanti, A; Thirion, C; Grandin, M [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1967-07-01

    Normally, these vehicles are used to reinforce the atmospheric supervision network based on four fixed stations. In the case of a planned atmospheric discharge they have to control contamination levels and check that these conform to the scattering forecasts. In the case of accidental atmospheric pollution, their role is to rapidly demarcate the pollution zones and to follow the evolution of this pollution. The main measurements carried out are: - Detection of ambient gamma radiation from 10 {mu}rad/hr to 1000 rad/hr. - Detection of the alpha and gamma contamination. - Detection of the beta and gamma contamination of the ground. (authors) [French] En temps normal, ces vehicules ont pour but de completer le reseau de surveillance atmospherique qui s'appuie sur quatre stations fixes. En cas de rejet atmospherique concerte, ils doivent controler les niveaux de contamination et verifier qu'ils sont conformes aux previsions de diffusion. En cas de rejet atmospherique accidentel, ils ont pour mission de delimiter rapidement les zones de pollution et tenir a jour leur evolution. Les principales mesures effectuees sont: - Detection des gamma ambiants de lO {mu}rad/h a 1000 rad/h. - Detection de la contamination atmospherique en alpha et beta. - Detection de la contamination du sol en beta et gamma. (auteurs)

  16. Avaliação de cultivares de soja, sob manejo orgânico, para fins de adubação verde e produção de grãos Evaluation of soybean cultivars under organic management for green manuring and grain production

    Directory of Open Access Journals (Sweden)

    Milton Parron Padovan

    2002-12-01

    Full Text Available O objetivo deste trabalho foi avaliar o desempenho de seis cultivares de soja, sob manejo orgânico, para fins de adubação verde e produção de grãos. Utilizou-se delineamento experimental de blocos casualizados, com quatro repetições por tratamento (cultivar. Na época da colheita, 81 dias após a emergência das plântulas, todas as cultivares testadas (Celeste, Surubi, Campo Grande, Mandi, Lambari e Taquari mostraram excelente nodulação, variando de 545 a 760 mg/planta de massa nodular seca. As cultivares Celeste e Taquari, que produziram, respectivamente, 8,33 e 7,12 t ha-1 de biomassa seca da parte aérea, apresentaram outras características agronômicas vantajosas, tais como: ciclo curto, alta acumulação de nutrientes (N, P, K, Ca e Mg nos tecidos verdes e bom rendimento de sementes. Esses caracteres indicam potencial de 'Celeste' e 'Taquari' para adubação verde de verão em sistemas de agricultura orgânica. Cinco das cultivares avaliadas revelaram tendência ao acamamento, porém dentro de níveis aceitáveis. As cultivares Celeste, Surubi, Campo Grande, Mandi e Taquari suplantaram em 23%, 32%, 33%, 44% e 70%, respectivamente, a média nacional de produtividade de soja, estimada em 2.398 kg ha-1 nas últimas três safras.The objective of this work was to evaluate the grain and aboveground biomass production of six soybean cultivars under organic management. A randomized block design was adopted with four replications per treatment (cultivar. By harvest time, 81 days after plants emergence, all tested cultivars (Celeste, Surubi, Campo Grande, Mandi, Lambari, and Taquari had excellent nodulation ranging from 545 to 760 mg/plant of nodule mass (dry weight. The cultivars Celeste and Taquari, which yielded 8.33 and 7.12 t ha-1 of dry biomass, respectively, showed other advantageous agronomic characteristics such as: short cycle, a high accumulation of nutrients (N, P, K, Ca and Mg in green tissues, and good seed setting. These

  17. Report on the emergency evacuation review team on emergency response plans for the Perry and Davis-Besse nuclear power plants

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    This book is a report by Ohio's Emergency Evacuation Review Team, at the request of Governor Richard Celeste. The Team concludes that the current emergency response plan for Ohio's reactors is inadequate to protect the public and recommends changes in the current emergency plant requirements. The report also includes a summary of the litigation that has occurred since Celeste withdrew his support for the plans, a list of experts consulted, and sources used to prepare the report. An important document, and a study which every state should undertake

  18. 77 FR 34212 - Irradiation in the Production, Processing, and Handling of Food

    Science.gov (United States)

    2012-06-11

    ...: Celeste Johnston, Center for Food Safety and Applied Nutrition (HFS-265), Food and Drug Administration... Salmonella growth. According to the study's results, the recovery of viable Salmonella bacteria from the... recovery of Salmonella from control oranges that were not etched by the carbon dioxide laser. The amount of...

  19. Deromancing leadership: what are the behaviours of highly effective middle managers?

    NARCIS (Netherlands)

    van der Weide, J.G.; Wilderom, Celeste P.M.

    2004-01-01

    Title: Deromancing leadership: what are the behaviours of highly effective middle managers? Author: Joost Van der Weide, Celeste Wilderom Address: University of Twente, Department of Management and Organizational Behaviour, P.O. Box 217, 7500 AE Enschede, The Netherlands. ' University of Twente,

  20. NOTES AND GLEANINGS / NOTE E CURIOSITÀ

    African Journals Online (AJOL)

    User

    del Novecento, da studi sulla poesia di Alba Florio e Alda Merini, De Marco ha progressivamente ...... come «libro di una vita, ricognizione e ricapitolazione degli snodi ..... trasumanato in «celeste», nell'apoteosi della luce d'oro della pittura.

  1. A new report of serpentinites from Northern Central Indian Ridge (at 6 degrees S) - An implication for hydrothermal activity

    Digital Repository Service at National Institute of Oceanography (India)

    Ray, Dwijesh; Banerjee, R.; Iyer, S.D.; Mukhopadhyay, S.

    from the Vityaz TF near 5"S, the Vema TF near gOS, the Argo TF near 13"S, the Marie Celeste FZ near 17"s and from the Melville TF near 30°S and 60°E (Engel and Fisher, 1975). Other occurrences of serpentinite and peridotites along the Indian Ocean...

  2. Numerical Analysis of Neutral Entrainment Effect on Field-Reversed Configuration Thruster Efficiency

    Science.gov (United States)

    2014-12-01

    Δx < ζλe in order to avoid the finite grid instability. Here, ωpe is the electron plasma frequency, and λe is the electron Debye length . In an...Celeste3D results in highly efficient simulations based on ion length and timescales (and not electron scales as explicit methods do) while retaining

  3. Giuseppe Bonaviri, Silvinia, Milano: Mondadori, 1997. Muovendo da ...

    African Journals Online (AJOL)

    User

    natura, tradizione, mito, sogno, magia, ignoto, memoria, mistero, scienza, fantascienza, filosofia, tempo, storia s'intrecciano ricreando il misterioso, pulsante delirio dell'universo. Temi tutti percorsi da quell'acceso lirismo che anima l'intera produzione poetica dello scrittore, ora raccolta ne Il dire celeste (1993). È un lucido ...

  4. Characterisation and quantification of trace metal elements in atmospheric deposition and particularities in the Aspe valley (Pyrenees): implementation of road traffic air quality indicators; Caracterisation et quantification des elements traces metalliques dans les depots et les particules atmospheriques de la vallee d'Aspe (Pyrenees): Mise en place d'indicateurs de la qualite de l'air lies au trafic routier

    Energy Technology Data Exchange (ETDEWEB)

    Veschambre, S

    2006-04-15

    This study of inputs of trace metal elements (TME) in the Aspe valley (Pyrenees Atlantiques) has two objectives: (1) to define a reference state of metallic contaminants for the monitoring of road traffic emissions since the opening of the Somport tunnel and, (2) to evaluate sources and climatic conditions which contribute to TME inputs in the Aspe valley. To establish air quality indicators, TME (Al, Na, Mg, K, V, Mn, Cr, Zn, Cu, Rb, Cd, Sn, Sb, Ba, Ce, Pb and U) and lead isotopic ratios ({sup 208}Pb/{sup 206}Pb, {sup 206}Pb/{sup 207}Pb and {sup 208}Pb/{sup 207}Pb) were determined in the atmospheric receptors (fresh snow, wet deposition, atmospheric particulates and lichen). Sampling and analyses with ultra clean procedures were employed for TME quantification. Variability of atmospheric receptors studied, allows integration on a daily and pluri-annual temporal scale and a spatial scale in the North-South axis of the valley and as a function of the altitude from the road. The Aspe valley presents a level of contamination characteristic of remote European areas and the metallic contaminants identified are Cd, Sb, Zn, Cu, Pb and Sn. In the low valley, air quality indicators indicate contaminant contributions (i) from local emissions of domestic heat sources, from agricultural burning practices and road traffic, and (ii) from regional anthropogenic sources of waste incinerators, metallurgic industries and urban centres. In altitude, the valley is significantly influenced by wind erosion and long range transport of TME in the Northern Hemisphere. Characterisation of TME and the isotopic ratios of Pb in the Somport tunnel indicate (i) a significant emission of Cu, Sb, Zn and Ba and (ii) an isotopic composition from a slightly radiogenic source even though Pb concentrations indicate low emissions from road traffic emissions. Nevertheless, the low traffic volume in the Aspe valley prevents conclusive evidence of significant contamination from road traffic. (author)

  5. N.3156 National Assembly law project authorizing the approbation of the protocol at the convention of 1979 on the long way transfrontier atmospheric pollution relative to the acidification, the eutrophication and the tropospheric ozone; N.3156 Assemblee Nationale projet de loi autorisant l'approbation du protocole a la convention de 1979 sur la pollution atmospherique transfrontiere a longue distance relatif a la reduction de l'acidification, de l'eutrophisation et de l'ozone tropospherique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    This document discusses the interest for the France of the approbation of the Goteborg protocol adopted in december 1999. It describes the main dispositions of the protocol relative to the reduction of the acidification and the eutrophication. (A.L.B.)

  6. VLF observations of ionospheric disturbances in association with TLEs from the EuroSprite-2007 campaign

    DEFF Research Database (Denmark)

    NaitAmor, S.; AlAbdoadaim, M. A.; Cohen, M. B.

    2010-01-01

    ) were captured over the Mediterranean Sea by cameras at Pic du Midi (42.94°N, 0.14°E) and at Centre de Recherches Atmospheriques (CRA) in southwestern France (43.13°N, 0.37°E). The cameras observations are compared to collected VLF AWESOME data. We consider early VLF perturbations observed on 12-13, 17...

  7. FTS improvements and connection with a long White cell. Application: H216O intensity measurements around 1200 cm-1

    International Nuclear Information System (INIS)

    Regalia, L.; Oudot, C.; Thomas, X.; Von der Heyden, P.; Decatoire, D.

    2010-01-01

    Acquisition electronics, data software and optics of the Fourier transform spectrometer of the Groupe de Spectrometrie Moleculaire et Atmospherique laboratory have been optimized over the past 5 years. Among the improvements brought on to this system is the optical fitting of 50-m White cell. This cell can be used to achieve absorption path lengths as long as 2 km. This new setup allows us to perform spectroscopic analysis of very small absorption lines.

  8. Possibility of observation by the Antares telescope of the gamma ray point sources observed by the Egret detector and study of a prototype

    International Nuclear Information System (INIS)

    Saouter, S.

    2004-09-01

    The ANTARES collaboration aims to install an underwater neutrino telescope at 2 500 m deep and 40 km away from Toulon (France). The neutrinos are detected thanks to their interaction by charged current in the medium surrounding the telescope which can be rock or water. The produced muon emits Tcherenkov light along its path in water. This light is detected by a three-dimensional network of 900 photomultipliers divided into 12 independent lines. To validate the chosen techniques, a prototype made up of a fifth of line was deployed in 2003. A reconstruction algorithm was developed on simulated data whose results are presented. However, a technical failure made the data recorded by the prototype unsuitable. The detection potential of Antares to gamma ray sources observed by Egret is studied. Indeed, under the assumption of a gamma ray production via high-energy hadrons, a comparable flux of neutrinos associated is predicted. By supposing the two fluxes equal and an energy spectrum varying as E -2 eleven sources are potentially detectable in one year. The Antares sensitivity to such a spectrum depends on the declination of the source with an optimum of 3.6 10 -4 m -2 s -1 GeV -1 in one year at 90% of confidence level for a declination of - 90 deg C. (author)

  9. Possibility of observation by the Antares telescope of the gamma ray point sources observed by the Egret detector and study of a prototype; Possibilite d'observation par le telescope Antares des sources ponctuelles de rayons gamma observees par le detecteur Egret et etude d'un prototype

    Energy Technology Data Exchange (ETDEWEB)

    Saouter, S

    2004-09-01

    The ANTARES collaboration aims to install an underwater neutrino telescope at 2 500 m deep and 40 km away from Toulon (France). The neutrinos are detected thanks to their interaction by charged current in the medium surrounding the telescope which can be rock or water. The produced muon emits Tcherenkov light along its path in water. This light is detected by a three-dimensional network of 900 photomultipliers divided into 12 independent lines. To validate the chosen techniques, a prototype made up of a fifth of line was deployed in 2003. A reconstruction algorithm was developed on simulated data whose results are presented. However, a technical failure made the data recorded by the prototype unsuitable. The detection potential of Antares to gamma ray sources observed by Egret is studied. Indeed, under the assumption of a gamma ray production via high-energy hadrons, a comparable flux of neutrinos associated is predicted. By supposing the two fluxes equal and an energy spectrum varying as E{sup -2} eleven sources are potentially detectable in one year. The Antares sensitivity to such a spectrum depends on the declination of the source with an optimum of 3.6 10{sup -4} m{sup -2} s{sup -1} GeV{sup -1} in one year at 90% of confidence level for a declination of - 90 deg C. (author)

  10. Possibility of observation by the Antares telescope of the gamma ray point sources observed by the Egret detector and study of a prototype; Possibilite d'observation par le telescope Antares des sources ponctuelles de rayons gamma observees par le detecteur Egret et etude d'un prototype

    Energy Technology Data Exchange (ETDEWEB)

    Saouter, S

    2004-09-01

    The ANTARES collaboration aims to install an underwater neutrino telescope at 2 500 m deep and 40 km away from Toulon (France). The neutrinos are detected thanks to their interaction by charged current in the medium surrounding the telescope which can be rock or water. The produced muon emits Tcherenkov light along its path in water. This light is detected by a three-dimensional network of 900 photomultipliers divided into 12 independent lines. To validate the chosen techniques, a prototype made up of a fifth of line was deployed in 2003. A reconstruction algorithm was developed on simulated data whose results are presented. However, a technical failure made the data recorded by the prototype unsuitable. The detection potential of Antares to gamma ray sources observed by Egret is studied. Indeed, under the assumption of a gamma ray production via high-energy hadrons, a comparable flux of neutrinos associated is predicted. By supposing the two fluxes equal and an energy spectrum varying as E{sup -2} eleven sources are potentially detectable in one year. The Antares sensitivity to such a spectrum depends on the declination of the source with an optimum of 3.6 10{sup -4} m{sup -2} s{sup -1} GeV{sup -1} in one year at 90% of confidence level for a declination of - 90 deg C. (author)

  11. The Inner Meaning of Outer Space:Human Nature and the Celestial Realm

    Directory of Open Access Journals (Sweden)

    Timothy L. Hubbard

    2009-11-01

    Full Text Available Kant afirmaba que los seres humanos poseen un conocimiento a priori del espacio. Aunque este argumento se centra en la física de los cuerpos, también tiene implicaciones para la psicología del ser. Muchas culturas humanas organizan las estrellas en constelaciones (imponen estructura; atribuyen propiedades, conductas y habilidades a objetos en el reino celeste (esto es, determinan significado; y usan la regularidad percibida en los reinos celestes para el desarrollo de calendarios, navegaciones de grandes distancias, agricultura y astrología (buscan predicción y control. La inaccesibilidad física del reino celeste permite una potente fuente de metáforas, así como la protección de los mitos sobre el origen y la ascensión, los lugares del poder y aquellos donde habitan dioses, seres inmortales y otras almas. Los desarrollos en astronomía y cosmología influyeron las opiniones sobre la naturaleza humana y el lugar de la humanidad en el universo; estos cambios ponen en paralelo los descensos en el egocentrismo y el desarrollo humano. Las visiones acerca de los presuntos seres (como los ángeles y los extraterrestres del reino celestial (y cómo comunicarse con esos seres son antropocéntricas e ignoran factores evolutivos del desarrollo físico y cognitivo. Se sugiere que al considerar opiniones y usos del reino celeste, aprendemos no sólo acerca del universo, sino también sobre nosotros mismos.

  12. Post-storage cell wall metabolism in two sweet cherry (Prunus avium L.) cultivars displaying different postharvest performance

    OpenAIRE

    Belge, Burcu; Comabella, Eva; Graell i Sarle, Jordi; Lara Ayala, Isabel

    2015-01-01

    The biochemical processes underlying firmness loss of sweet cherry (Prunus avium L.) fruit are poorly understood.Studies on cell wall metabolism of sweet cherry have been generally undertaken during on-tree development or at harvest maturity, while published reports on postharvest changes are scarce and fragmentary. In this work, cell wall modifications after storage at 0 ºC were studied in two cherry cultivars ('Celeste' and 'Somerset') displaying different postharvest potential. Firmness wa...

  13. Reflectivity around the gold L-edges of X-ray reector of the soft X-ray telescope onboard ASTRO-H

    DEFF Research Database (Denmark)

    Maeda, Yoshitomo; Kikuchi, Naomichi; Kurashima, Sho

    2017-01-01

    We report the atomic scattering factor in the 11.2-15.4 keV for the ASTRO-H Soft X-ray Telescope (SXT)9 obtained in the ground based measurements. The large effective area of the SXT covers above 10 keV. In fact, the flight data show the spectra of the celestical objects in the hard X-ray band. I...

  14. Afnor NF D 35-330. Gas-fired central heating boilers. Type B{sub 11} and B{sub 11BIS} boilers fitted with atmospheric burners of nominal heat input not exceeding 70 kW. (European standard EN 297); Afnor NF D 35-330. Chaudieres de chauffage central utilisant les combustibles gazeux. Chaudieres des types B{sub 11} et B{sub 11BIS} equipees de bruleurs atmospheriques dont le debit calorifique nominal est inferieur ou egal a 70 kW. (Norme europeenne EN 297)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-10-01

    This standard document defines the specifications and testing techniques relative to the manufacturing, safety, energy rational use, functioning capacity, classification and labeling of gas-fueled heating plants. It replaces the previous NF D 35-331 norm from November 1989 which comprised the NF D 35-331 norm from January 1980, its additives 1 (January 1980) and 2 (June 1984), its modifications 1 (July 1980), 2 (September 1986), 3 (December 1988) and 4 (November 1989) and the D 30-005 experimental norm of November 1991. (J.S.)

  15. No.3605 report realized by the name of the Foreign Affairs Commission on the law project (no. 3156), authorizing the approbation of the protocol to the 1979 convention on the long distance transfrontier atmospheric pollution relative to the reduction of the acidification, the eutrophication and the tropospheric ozone (nine annexes); No. 3605 rapport fait au nom de la Commission des Affaires Etrangeres sur le projet de Loi (no. 3156), autorisant l'approbation du protocole a la convention de 1979 sur la pollution atmospherique transfrontiere a longue distance relatif a la reduction de l'acidification, de l'eutrophisation et de l'ozone tropospherique (ensemble neuf annexes)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-01-15

    In the framework of the 1979 convention (of Geneva), eight specific protocols have been adopted, amongch the Goteborg protocol on the long distance transfrontier atmospheric pollution. It aims to reduce of 40% to 2010, the emissions of three pollutants (sulfur dioxide, nitrogen oxides and volatile organic compounds). In this context this report presents the reinforcement of the international tools of fight against the atmospheric pollution and the Goteborg protocol in the existing devices of the air pollution abatement. (A.L.B.)

  16. Panorama histórico del estudio de los planetas del sistema solar

    Directory of Open Access Journals (Sweden)

    Fernando Francisco López-Gómez

    2016-01-01

    Full Text Available Se presenta un recorrido por los momentos más significativos de la historia de la astronomía. Se señalan los descubrimientos trascendentales que han modificado la visión que se tenía de los planetas, las estrellas y otros cuerpos celestes. A partir de un recuento de los retos más significativos a los que se enfrenta la astronomía, se argumenta en favor de hacer estudios historiográficos sobre esta ciencia. Finalmente, se subraya la necesidad de acercar estos conocimientos al público no especializado.

  17. Basic Color Terms (BCTs) and Categories (BCCs) in Three Dialects of the Spanish Language: Interaction Between Cultural and Universal Factors

    Science.gov (United States)

    Lillo, Julio; González-Perilli, Fernando; Prado-León, Lilia; Melnikova, Anna; Álvaro, Leticia; Collado, José A.; Moreira, Humberto

    2018-01-01

    Two experiments were performed to identify and compare the Basic Color Terms (BCTs) and the Basic Color Categories (BCCs) included in three dialects (Castilian, Mexican, and Uruguayan) of the Spanish language. Monolexemic Elicited lists were used in the first experiment to identify the BCTs of each dialect. Eleven BCTs appeared for the Spanish and the Mexican, and twelve did so for the Uruguayan. The six primary BCTs (rojo “red,” verde “green,” amarillo “yellow,” azul “blue,” negro “black,” and blanco “white”) appeared in the three dialects. This occurred for only three derived BCTs (gris “gray,” naranja “orange,” and rosa “pink”) but not for the other five derived BCTs (celeste “sky blue,” marrón “brown,” café “brown,” morado “purple,” and violeta “purple”). Color transitions were used in the second experiment for two different tasks. Extremes naming task was used to determine the relation between two different dialects' BCTs: equality, equivalence or difference. The results provided the first evidence for marrón “brown” and café “brown” being equivalent terms for the same BCC (brown in English) as is the case of morado “purple” and violeta “purple.” Uruguayan celeste “sky blue” had no equivalent BCT in the other two dialects. Boundary delimitation task required the selection of the color in the boundary between two categories. The task was used to reasonably estimate the volume occupied by each BCC in the color space considering its chromatic area and lightness range. Excluding sky blue (celeste “sky blue”) and blue (azul “blue”), the other BCCs color volumes were similar across the three dialects. Uruguayan sky blue and blue volumes conjointly occupied the portion of the color space corresponding to the Castilian and Mexican blue BCC. The fact that the BCT celeste “sky blue” only appeared in Uruguayan very probably derived from specific cultural factors (the use of the

  18. La mecánica de fluidos y la teoría de la figura de la Tierra entre Newton y Clairaut (1687-1743)

    OpenAIRE

    Lafuente, Antonio

    1983-01-01

    El objeto de este artículo es analizar la literatura publicada sobre el tema de la figura de la Tierra entre 1687 y 1743. La primera fecha coincide con la publicación de los Philosophiae Naturalis Principia Mathematica. El estudio de Newton demostraba la insuficiencia de recursos de la ciencia experimental y el abismo existente entre la precisión que podían asegurar los métodos de la astronomía práctica y las nuevas exigencias planteadas por su mecánica celeste. La segunda fech...

  19. Astronomia diurna

    OpenAIRE

    Gangui, Alejandro

    2017-01-01

    Durante los equinoccios, la secuencia temporal de las sombras proyectadas por cada uno de los puntos que forman cualquier objeto sigue una línea recta de oeste a este. Una construcción simple con hilos y un gnomon puede ser utilizada para materializar el plano de la proyección local del ecuador celeste, lo que nos ofrece una manera de calcular nuestra latitud astronómica durante el día con alta precisión. Se presenta un experimento que se puede realizar en horario diurno para ayudar a los est...

  20. Basic Color Terms (BCTs and Categories (BCCs in Three Dialects of the Spanish Language: Interaction Between Cultural and Universal Factors

    Directory of Open Access Journals (Sweden)

    Julio Lillo

    2018-05-01

    Full Text Available Two experiments were performed to identify and compare the Basic Color Terms (BCTs and the Basic Color Categories (BCCs included in three dialects (Castilian, Mexican, and Uruguayan of the Spanish language. Monolexemic Elicited lists were used in the first experiment to identify the BCTs of each dialect. Eleven BCTs appeared for the Spanish and the Mexican, and twelve did so for the Uruguayan. The six primary BCTs (rojo “red,” verde “green,” amarillo “yellow,” azul “blue,” negro “black,” and blanco “white” appeared in the three dialects. This occurred for only three derived BCTs (gris “gray,” naranja “orange,” and rosa “pink” but not for the other five derived BCTs (celeste “sky blue,” marrón “brown,” café “brown,” morado “purple,” and violeta “purple”. Color transitions were used in the second experiment for two different tasks. Extremes naming task was used to determine the relation between two different dialects' BCTs: equality, equivalence or difference. The results provided the first evidence for marrón “brown” and café “brown” being equivalent terms for the same BCC (brown in English as is the case of morado “purple” and violeta “purple.” Uruguayan celeste “sky blue” had no equivalent BCT in the other two dialects. Boundary delimitation task required the selection of the color in the boundary between two categories. The task was used to reasonably estimate the volume occupied by each BCC in the color space considering its chromatic area and lightness range. Excluding sky blue (celeste “sky blue” and blue (azul “blue”, the other BCCs color volumes were similar across the three dialects. Uruguayan sky blue and blue volumes conjointly occupied the portion of the color space corresponding to the Castilian and Mexican blue BCC. The fact that the BCT celeste “sky blue” only appeared in Uruguayan very probably derived from specific cultural factors (the

  1. Basic Color Terms (BCTs) and Categories (BCCs) in Three Dialects of the Spanish Language: Interaction Between Cultural and Universal Factors.

    Science.gov (United States)

    Lillo, Julio; González-Perilli, Fernando; Prado-León, Lilia; Melnikova, Anna; Álvaro, Leticia; Collado, José A; Moreira, Humberto

    2018-01-01

    Two experiments were performed to identify and compare the Basic Color Terms (BCTs) and the Basic Color Categories (BCCs) included in three dialects (Castilian, Mexican, and Uruguayan) of the Spanish language. Monolexemic Elicited lists were used in the first experiment to identify the BCTs of each dialect. Eleven BCTs appeared for the Spanish and the Mexican, and twelve did so for the Uruguayan. The six primary BCTs ( rojo "red," verde "green," amarillo "yellow," azul "blue," negro "black," and blanco "white") appeared in the three dialects. This occurred for only three derived BCTs ( gris "gray," naranja "orange," and rosa "pink") but not for the other five derived BCTs ( celeste "sky blue," marrón "brown," café "brown," morado "purple," and violeta "purple"). Color transitions were used in the second experiment for two different tasks. Extremes naming task was used to determine the relation between two different dialects' BCTs: equality, equivalence or difference. The results provided the first evidence for marrón "brown" and café "brown" being equivalent terms for the same BCC (brown in English) as is the case of morado "purple" and violeta "purple." Uruguayan celeste "sky blue" had no equivalent BCT in the other two dialects. Boundary delimitation task required the selection of the color in the boundary between two categories. The task was used to reasonably estimate the volume occupied by each BCC in the color space considering its chromatic area and lightness range. Excluding sky blue ( celeste "sky blue") and blue ( azul "blue"), the other BCCs color volumes were similar across the three dialects. Uruguayan sky blue and blue volumes conjointly occupied the portion of the color space corresponding to the Castilian and Mexican blue BCC. The fact that the BCT celeste "sky blue" only appeared in Uruguayan very probably derived from specific cultural factors (the use of the color in the flags and the arrival of an important number of Italian immigrants

  2. Intermediarios radiales del movimiento roto-traslatorio de satélites artificiales

    OpenAIRE

    Soler Vera, Francisco Alejandro

    2016-01-01

    En esta tesis se presentan algunos modelos intermediarios del movimiento roto-traslatorio de un satélite u otro cuerpo celeste menor alrededor de uno esférico y mucho más masivo, considerando condiciones iniciales para las cuales la perturbación gravitatoria es la predominante sobre otros tipos de perturbaciones como la magnética o la aerodinámica, entre otras. En particular, analizaremos el conocido como “problema de gradiente de gravedad”, esto es, la aproximación de MacCullagh del desarr...

  3. Partnership between the school of nursing and the hospital: supervisors' perspectives

    OpenAIRE

    Martins, Cristina Araújo; Macedo, Ana Paula; Araújo, Odete; Oliveira, Cláudia; Braga, Maria de Fátima Dias; Gomes, Lisa Alves; Silva, Maria Augusta; Rosário, Rafaela

    2016-01-01

    Table of contents S1 Health literacy and health education in adolescence Catarina Cardoso Tom?s S2 The effect of a walking program on the quality of life and well-being of people with schizophrenia Emanuel Oliveira, D. Sousa, M. Uba-Chupel, G. Furtado, C. Rocha, A. Teixeira, P. Ferreira S3 Diagnosis and innovative treatments - the way to a better medical practice Celeste Alves S4 Simulation-based learning and how it is a high contribution Stefan Gisin S5 Formative research about acceptability...

  4. Elusive Ethylene Detected in Saturns Northern Storm Region

    Science.gov (United States)

    Hesman, B. E.; Bjoraker, G. L.; Sada, P. V.; Achterberg, R. K.; Jennings, D. E.; Romani, P. N.; Lunsford, A. W.; Fletcher, L. N.; Boyle, R. J.; Simon-Miller, A. A.; hide

    2013-01-01

    The massive eruption at 40 deg. N (planetographic latitude) on Saturn in 2010 December has produced significant and lasting effects in the northern hemisphere on temperature and species abundances. The northern storm region was observed on many occasions in 2011 by Cassini's Composite Infrared Spectrometer (CIRS). In 2011 May, temperatures in the stratosphere greater than 200 K were derived from CIRS spectra in the regions referred to as "beacons" (warm regions in the stratosphere). Ethylene has been detected in the beacon region in Saturn's northern storm region using CIRS. Ground-based observations using the high-resolution spectrometer Celeste on the McMath-Pierce Telescope on 2011 May 15 were used to confirm the detection and improve the altitude resolution in the retrieved profile. The derived ethylene profile from the CIRS data gives a C2H4 mole fraction of 5.9 +/- 4.5 x 10(exp -7) at 0.5 mbar, and from Celeste data it gives 2.7 +/- 0.45 x 10(exp -6) at 0.1 mbar. This is two orders of magnitude higher than the amount measured in the ultraviolet at other latitudes prior to the storm. It is also much higher than predicted by photochemical models, indicating that perhaps another production mechanism is required or a loss mechanism is being inhibited.

  5. Secondary resonances and the boundary of effective stability of Trojan motions

    Science.gov (United States)

    Páez, Rocío Isabel; Efthymiopoulos, Christos

    2018-02-01

    One of the most interesting features in the libration domain of co-orbital motions is the existence of secondary resonances. For some combinations of physical parameters, these resonances occupy a large fraction of the domain of stability and rule the dynamics within the stable tadpole region. In this work, we present an application of a recently introduced `basic Hamiltonian model' H_b for Trojan dynamics (Páez and Efthymiopoulos in Celest Mech Dyn Astron 121(2):139, 2015; Páez et al. in Celest Mech Dyn Astron 126:519, 2016): we show that the inner border of the secondary resonance of lowermost order, as defined by H_b, provides a good estimation of the region in phase space for which the orbits remain regular regardless of the orbital parameters of the system. The computation of this boundary is straightforward by combining a resonant normal form calculation in conjunction with an `asymmetric expansion' of the Hamiltonian around the libration points, which speeds up convergence. Applications to the determination of the effective stability domain for exoplanetary Trojans (planet-sized objects or asteroids) which may accompany giant exoplanets are discussed.

  6. ELUSIVE ETHYLENE DETECTED IN SATURN'S NORTHERN STORM REGION

    Energy Technology Data Exchange (ETDEWEB)

    Hesman, B. E.; Achterberg, R. K.; Nixon, C. A. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Bjoraker, G. L.; Romani, P. N. [NASA/GSFC Code 693, Greenbelt, MD 20771 (United States); Sada, P. V. [Departamento de Fisica y Matematicas, Universidad de Monterrey, Garza Garcia, NL 66238 (Mexico); Jennings, D. E. [NASA/GSFC Code 693 and Code 500, Greenbelt, MD 20771 (United States); Lunsford, A. W. [Department of Physics, Catholic University of America, Washington, DC 20064 (United States); Fletcher, L. N.; Irwin, P. G. J. [Atmospheric, Oceanic and Planetary Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU (United Kingdom); Boyle, R. J. [Department of Physics and Astronomy, Dickinson College, Carlisle, PA 17013 (United States); Simon-Miller, A. A., E-mail: brigette.e.hesman@nasa.gov [NASA/GSFC Code 690, Greenbelt, MD 20771 (United States)

    2012-11-20

    The massive eruption at 40 Degree-Sign N (planetographic latitude) on Saturn in 2010 December has produced significant and lasting effects in the northern hemisphere on temperature and species abundances. The northern storm region was observed on many occasions in 2011 by Cassini's Composite Infrared Spectrometer (CIRS). In 2011 May, temperatures in the stratosphere greater than 200 K were derived from CIRS spectra in the regions referred to as 'beacons' (warm regions in the stratosphere). Ethylene has been detected in the beacon region in Saturn's northern storm region using CIRS. Ground-based observations using the high-resolution spectrometer Celeste on the McMath-Pierce Telescope on 2011 May 15 were used to confirm the detection and improve the altitude resolution in the retrieved profile. The derived ethylene profile from the CIRS data gives a C{sub 2}H{sub 4} mole fraction of 5.9 {+-} 4.5 Multiplication-Sign 10{sup -7} at 0.5 mbar, and from Celeste data it gives 2.7 {+-} 0.45 Multiplication-Sign 10{sup -6} at 0.1 mbar. This is two orders of magnitude higher than the amount measured in the ultraviolet at other latitudes prior to the storm. It is also much higher than predicted by photochemical models, indicating that perhaps another production mechanism is required or a loss mechanism is being inhibited.

  7. Um objeto-modelo didático do movimento aparente do Sol em relação ao fundo de estrelas

    Directory of Open Access Journals (Sweden)

    Francisco Catelli

    2013-04-01

    “Por que o Sol nunca passa pela constelação de Órion?” A resposta a essa pergunta, feita por um aluno, inicia com uma revisão da literatura sobre modelos, em especial aqueles relacionados aos objetos-modelo didáticos. A pergunta é respondida, então, inicialmente, usando um mapa do céu, o qual é, em seguida, transformado em um cilindro, e este, por sua vez, é montado em um dispositivo didático de modo a materializar o movimento aparente da abóbada celeste, em uma latitude escolhida, constituindo-se, assim, em um verdadeiro “mini planetário”. Contudo, para chegar a um nível de resposta que inclua conceitos como o da vertical do lugar, a invariância da orientação do eixo de rotação da Terra, o equador celeste e a eclíptica, fazem-se necessários outros modelos. Por fim, conclui-se que não é apenas um, mas sim um conjunto articulado de modelos que pode levar a uma resposta aceitável à questão proposta.

  8. Study of a high surface gas triode for detecting atomic or nuclear particles; Etude d'une triode a gaz a grande surface detectrice de particules atomiques ou nucleaires

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-06-15

    A triode filled with xenon at atmospheric pressure can be used as an X-ray detector since it produces an appreciable amount of light per quantum absorbed. Various methods are described for studying and reducing the deadtime after the passage of a spark. This detector can be used in medicine for the detection of tumours and also for the rapid recording of diffraction diagrams. (author) [French] Une triode, remplie de xenon a la pression atmospherique, sert de detecteur de rayors X en fournissant une quantite de lumiere importante par quantum absorbe. Diverses methodes sont decrites permettant d'etudier et de reduire le temps mort apres le passage d'une etincelle. Ce detecteur sert a la localisation de tumeurs en medecine et a l'enregistrement rapide de diagrammes de diffraction. (auteur)

  9. Modeling the energy balance in Marseille: Sensitivity to roughness length parameterizations and thermal admittance

    Science.gov (United States)

    Demuzere, M.; De Ridder, K.; van Lipzig, N. P. M.

    2008-08-01

    During the ESCOMPTE campaign (Experience sur Site pour COntraindre les Modeles de Pollution atmospherique et de Transport d'Emissions), a 4-day intensive observation period was selected to evaluate the Advanced Regional Prediction System (ARPS), a nonhydrostatic meteorological mesoscale model that was optimized with a parameterization for thermal roughness length to better represent urban surfaces. The evaluation shows that the ARPS model is able to correctly reproduce temperature, wind speed, and direction for one urban and two rural measurements stations. Furthermore, simulated heat fluxes show good agreement compared to the observations, although simulated sensible heat fluxes were initially too low for the urban stations. In order to improve the latter, different roughness length parameterization schemes were tested, combined with various thermal admittance values. This sensitivity study showed that the Zilitinkevich scheme combined with and intermediate value of thermal admittance performs best.

  10. Study of a high surface gas triode for detecting atomic or nuclear particles; Etude d'une triode a gaz a grande surface detectrice de particules atomiques ou nucleaires

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-06-15

    A triode filled with xenon at atmospheric pressure can be used as an X-ray detector since it produces an appreciable amount of light per quantum absorbed. Various methods are described for studying and reducing the deadtime after the passage of a spark. This detector can be used in medicine for the detection of tumours and also for the rapid recording of diffraction diagrams. (author) [French] Une triode, remplie de xenon a la pression atmospherique, sert de detecteur de rayors X en fournissant une quantite de lumiere importante par quantum absorbe. Diverses methodes sont decrites permettant d'etudier et de reduire le temps mort apres le passage d'une etincelle. Ce detecteur sert a la localisation de tumeurs en medecine et a l'enregistrement rapide de diagrammes de diffraction. (auteur)

  11. Oxidation of steel heated in CO{sub 2} medium under pressure; Oxydation d'un acier ordinaire chauffe dans le gaz carbonique sous pression

    Energy Technology Data Exchange (ETDEWEB)

    Darras, R.; Leclercq, D.; Bunard, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    Behaviour of low-alloyed steels heated in CO{sub 2} medium under pressure is reported. Tests are carried out in the range of erature reached in the CO{sub 2} cooled reactors (vessel, thermal shield, pipes). The observed weight increases are small, even after more than a thousand hours of heating at 350 deg. C, but oxidation curve looks like progressing linearly. Furthermore, the oxide formed under a pressure of 15 kg/cm{sup 2} is undoubtedly more compact and adherent than the one formed under a pressure of 1 kg/cm{sup 2}. Finally, for practical use, CO{sub 2} steel pipes surface has to be sand blast and pickled. A following phosphatizing protects it from atmospheric corrosion during assembling, but these treatments have no influence on the behaviour of these steels heated in CO{sub 2}. (author)Fren. [French] On etudie le comportement d'aciers au carbone faiblement allies, chauffes dans le gaz carbonique sous pression, aux temperatures atteintes dans les reacteurs refroidis par ce gaz (caisson, bouclier thermique, canalisations). Les augmentations de poids observees sont faibles, meme apres plus de 1000 heures de chauffage a 350 deg. C, mais l'oxydation semble se poursuivre lineairement. De plus, l'oxyde forme dans le gaz carbonique sous pression de 15 kg/cm{sup 2} est nettement plus compact et adherent que celui forme sous pression atmospherique de gaz carbonique. Enfin, dans la pratique, les surfaces d'acier du circuit de gaz carbonique sont necessairement sablees ou decapees; une phosphatation ulterieure le protege de la corrosion atmospherique pendant le montage. Ces traitements sont sans influence sur le comportement de ces aciers dans le gaz carbonique a chaud. (auteur)

  12. Oxidation of steel heated in CO{sub 2} medium under pressure; Oxydation d'un acier ordinaire chauffe dans le gaz carbonique sous pression

    Energy Technology Data Exchange (ETDEWEB)

    Darras, R; Leclercq, D; Bunard, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    Behaviour of low-alloyed steels heated in CO{sub 2} medium under pressure is reported. Tests are carried out in the range of erature reached in the CO{sub 2} cooled reactors (vessel, thermal shield, pipes). The observed weight increases are small, even after more than a thousand hours of heating at 350 deg. C, but oxidation curve looks like progressing linearly. Furthermore, the oxide formed under a pressure of 15 kg/cm{sup 2} is undoubtedly more compact and adherent than the one formed under a pressure of 1 kg/cm{sup 2}. Finally, for practical use, CO{sub 2} steel pipes surface has to be sand blast and pickled. A following phosphatizing protects it from atmospheric corrosion during assembling, but these treatments have no influence on the behaviour of these steels heated in CO{sub 2}. (author)Fren. [French] On etudie le comportement d'aciers au carbone faiblement allies, chauffes dans le gaz carbonique sous pression, aux temperatures atteintes dans les reacteurs refroidis par ce gaz (caisson, bouclier thermique, canalisations). Les augmentations de poids observees sont faibles, meme apres plus de 1000 heures de chauffage a 350 deg. C, mais l'oxydation semble se poursuivre lineairement. De plus, l'oxyde forme dans le gaz carbonique sous pression de 15 kg/cm{sup 2} est nettement plus compact et adherent que celui forme sous pression atmospherique de gaz carbonique. Enfin, dans la pratique, les surfaces d'acier du circuit de gaz carbonique sont necessairement sablees ou decapees; une phosphatation ulterieure le protege de la corrosion atmospherique pendant le montage. Ces traitements sont sans influence sur le comportement de ces aciers dans le gaz carbonique a chaud. (auteur)

  13. Realisation of a linear electron accelerator. Application to the production of millimetre wavelength waves; Realisation d'un accelerateur lineaire d'electrons. Application a la production d'ondes millimetriques

    Energy Technology Data Exchange (ETDEWEB)

    Combe, Rene

    1956-06-27

    , distributions angulaire et spectrale du rayonnement; comparaison des rayonnements de l'ondulateur, du betatron et de l'effet Tcherenkov. Enfin au chapitre V, nous decrivons nos experiences, faites avec un ondulateur de chaque type.

  14. Abusir 3D survey 2015

    Directory of Open Access Journals (Sweden)

    Yukinori Kawae

    2016-12-01

    Full Text Available In 2015, in collaboration with the Czech Institute of Egyptology, we, a Japanese consortium, initiated the Abusir 3D Survey (A-3DS for the 3D documentation of the site’s pyramids, which have not been updated since the time of the architectural investigations of Vito Maragioglio and Celeste Rinaldi in the 1960s to the 1970s. The first season of our project focused on the exterior of Neferirkare’s pyramid, the largest pyramid at Abusir. By developing a strategic mathematical 3D survey plan, step-by-step 3D documentation to suit specific archaeological needs, and producing a new display method for the 3D data, we successfully measured the dimensions of the pyramid in a cost-effective way.

  15. Na Cauda do Cometa

    Science.gov (United States)

    Voelzke, M. R.

    2009-01-01

    Quando viam um cometa, os antigos gregos imaginavam uma estrela com uma vasta cabeleira. Não à toa, a palavra deriva do termo koma, que significa cabelo. Constituídos por fragmentos de gelo e gases, os cometas possuem um núcleo sólido, que pode ter vários quilômetros de diâmetro, e uma cauda que sempre aponta na direção contrária ao Sol, devido aos ventos solares. Graças à aparência de pontos luminosos em movimento (ao contrário de outros astros, que parecem estáticos), esses corpos celestes foram interpretados por diferentes povos com muito misticismo, inspirando mitos tanto de boas-novas como de maus presságios. Conheça algumas dessas histórias:

  16. LA DIALÉCTICA DE FE Y RAZÓN EN EL MUNDO CONTEMPORÁNEO

    Directory of Open Access Journals (Sweden)

    H.C.F Mansilla

    2007-12-01

    Full Text Available El optimismo del pensamiento moderno pronosticó el fin de la religión, considerándola un mero fetiche de la ignorancia e incapacidad humana. Una mera ilusión que alienaba a las masas del mundo terrenal por una fantasía celeste. Sin embargo la religión logró capear las tormentas cientificistas hasta la década del sesenta del siglo XX. Paulatinamente la religión comenzó a ser vista como una institución humana que se vivificaba como nunca antes, trayendo esperanza, consuelo y confianza al ser humano ante los desencanto de la modernización incumplida de la política y la economía.

  17. La dialéctica de fe y razón en el mundo contemporáneo

    Directory of Open Access Journals (Sweden)

    H. C. F. Mansilla

    2007-06-01

    Full Text Available El optimismo del pensamiento moderno pronosticó el fin de la religión, considerándola un mero fetiche de la ignorancia e incapacidad humana. Una mera ilusión que alienaba a las masas del mundo terrenal por una fantasía celeste. Sin embargo la religión logró capear las tormentas cientificistas hasta la década del sesenta del siglo XX. Paulatinamente la religión comenzó a ser vista como una institución humana que se vivificaba como nunca antes, trayendo esperanza, consuelo y confianza al ser humano ante los desencanto de la modernización incumplida de la política y la economía.

  18. El mundo del libro: septiembre de 1964

    Directory of Open Access Journals (Sweden)

    Agustín Rodríguez Garavito

    1964-09-01

    Full Text Available El documento presenta las reseñas de los siguientes títulos: Los pasos en la sombra -Por Helcías Martán Góngora -Poesía- Ediciones Medusa. Colombia. Diccionario Biográfico de Artistas delNuevo Reino de Granada - Edición: Instituto Colombiano de Cultura Hispánica. Bogotá. Artículos y Ensayos -Por José Joaquín Vargas Valdés -Introducción y Selección de Aníbal Vargas Barón -Universidad de Oregón. U.S.A. De lo celeste y tenebroso -Gabriel Uliosa -Poemas- Editorial Iqueima. San Andrés y Providencia -James J. Parsons. -Talleres Gráficos del Banco de la República -Bogotá-Colombia

  19. Le costellazioni al binocolo Trecento oggetti celesti da riconoscere ed esplorare

    CERN Document Server

    Kambič, Bojan

    2013-01-01

    Questo libro è un tour guidato attraverso le costellazioni visibili dalle medie latitudini settentrionali. È un’opera ideale per chi si accosta per la prima volta all’osservazione del cielo, ma anche l’astrofilo esperto la troverà ricca e utile, per come è strutturata. Nella prima parte, il libro è un succinto trattatello di astronomia, di meccanica celeste, d’evoluzione stellare e di cosmologia. Nella seconda parte, vengono proposte mappe per riconoscere tutte le costellazioni visibili dai nostri cieli, e schede con informazioni particolareggiate relative alle stelle visibili a occhio nudo, oltre che ad alcune centinaia di oggetti (stelle doppie e variabili, ammassi stellari, nebulose, galassie) alla portata di un semplice binocolo 10×50.

  20. The Tranisiting Dust of Boyajian's Star

    Science.gov (United States)

    Bodman, Eva; Ellis, Tyler G.; Boyajian, Tabetha S.; Wright, Jason

    2018-06-01

    From May to October of 2017, Boyajian's Star displayed four days-long dips in observed flux, which are referred to as “Elsie,” “Celeste,” “Skara Brae,” and “Angkor” (Boyajian et al. 2018). This Elsie family dip event was monitored with the Las Cumbres Observatory in three bands, B, r', and i'. Looking at each dip individually, we analyze the multi-band photometry for wavelength dependency in dip depth to constrain properties of the transiting material. We find that all of the dips show non-grey extinction and are consistent with optically thin dust. Interpreting the dips as transiting dust clouds, we constrain the properties of the dust grains and find that the average grain radius is causing the dips is from a separate population.

  1. La aventura de la exploración de Marte

    OpenAIRE

    Vázquez Martínez, Luis

    2013-01-01

    Resumen La exploración del planeta Marte forma parte de un objetivo científico de largo alcance: entender la formación y la historia del Sistema Solar, saber no sólo cómo son hoy en día todos los cuerpos celestes que lo forman, sino cómo fueron en otros tiempos geológicos, cómo se formaron, si en ellos se dieron condiciones para que se desarrollase vida como ocurrió en la Tierra. En este contexto científico se ha de resaltar la participación activa de la Universidad Complutense de Madr...

  2. Estructura orbital en el Problema Restringido Rectilíneo Isósceles

    Science.gov (United States)

    Orellana, R. B.

    Para definir problemas en Mecánica Celeste se utilizan diferentes parámetros. El conocimiento de la dinámica del problema para valores particulares de estos parámetros nos permite entender el comportamiento en casos más generales. El Problema Restringido Rectilíneo Isósceles puede ser considerado como el caso límite del Problema de Sitnikov cuando la excentricidad tiende a uno o como el Problema Isósceles cuando la masa central tiende a cero. Se ha compactificado el espacio de fases y analizado la dinámica en el límite. Esto ha permitido separar el espacio de fases en diferentes regiones dependiendo de las clases de órbitas.

  3. Estudo sobre a historiografia japonesa

    Directory of Open Access Journals (Sweden)

    Ricardo Mário Gonçalves

    1964-06-01

    Full Text Available A cultura japonêsa não se desenvolveu independentemen-te de contactos com as culturas dos outros povos do Oriente, muito pelo contrário, grande parte dela é derivada da cultu-ra chinesa, com que o Japão entrou em contacto desde o iní-cio da éra cristã através de relações comerciais com o Celes-te Império e da entrada no Japão de inúmeros imigrantes chi-neses e coreanos, bem como da cultura hindu, com que en-trou em contacto indireto ao assimilar o Budismo que lhe foi transmitido da China.

  4. Analytical control of reducing agents on uranium/plutonium partitioning at purex process

    International Nuclear Information System (INIS)

    Araujo, Izilda da Cruz de

    1995-01-01

    Spectrophotometric methods for uranium (IV), hydrazine (N 2 H 4 ) and its decomposition product hydrazoic acid(HN 3 ), and hydroxylamine (NH 2 OH) determinations were developed aiming their applications for the process control of CELESTE I installation at IPEN/CNEN-SP. These compounds are normally present in the U/Pu partitioning phase of the spent nuclear treatment via PUREX process. The direct spectrophotometry was used for uranium (IV) analysis in nitric acid-hydrazine solutions based on the absorption measurement at 648 nm. The azomethine compound formed by reaction of hydrazine and p-dimethylamine benzaldehyde with maximum absorption at 457 nm was the basis for the specific analytical method for hydrazine determination. The hydrazoic acid analysis was performed indirectly by its conversion into ferric azide complex with maximum absorption at 465 nm. The hydroxylamine detection was accomplished based on its selective oxidation to nitrous acid which is easily analyzed by the reaction with Griess reagent. The resulted azocompound gas a maximum absorption at 520 nm. The sensibility of 1,4x10 -6 M for U(IV) with 0,8% of precision, 1,6x10 -6 M for hydrazine with 0,8% of precision, 2,3x10 -6 M hydrazoic acid with 0,9% of precision and 2,5x10 -6 M for hydroxylamine with 0,8% of precision were achieved. The interference studies have shown that each reducing agent can be determined in the presence of each other without any interference. Uranium(VI) and plutonium have also shown no interference in these analysis. The established methods were adapted to run inside glove-boxes by using an optical fiber colorimetry and applied to process control of the CELESTE I installation. The results pointed out that the methods are reliable and safety in order to provide just-in-time information about process conditions. (author)

  5. Metazoan parasites of fishes from the Celestun coastal lagoon, Yucatan, Mexico.

    Science.gov (United States)

    Sosa-Medina, Trinidad; Vidal-Martínez, Víctor M; Aguirre-Macedo, M Leopoldina

    2015-08-31

    The aims of this study were to produce a checklist of the metazoan parasites of fishes from the Celestun coastal lagoon and to determine the degree of faunal similarity among the fishes based on the metazoan parasites they share. A checklist was prepared including all available records (1996-2014) of parasites of marine, brackish water and freshwater fishes of the area. All of these data were included in a presence/absence database and used to determine similarity via Jaccard's index. The results indicate the presence of 62 metazoan parasite species infecting 22 fish species. The number of metazoan parasite species found in the fishes from the Celestún lagoon is apparently the highest reported worldwide for a tropical coastal lagoon. The parasites included 12 species of adult digeneans, 27 digeneans in the metacercarial stage, 6 monogeneans, 3 metacestodes, 9 nematodes, 2 acanthocephalans, 2 crustaceans and 1 annelid. Forty parasite species were autogenic and 23 were allogenic and 1 unknown. The overall similarity among all of the species of fish with respect to the metazoan parasites they share was low (0.08 ± 0.12), with few similarity values above 0.4 being obtained. This low similarity was due primarily to the presence of suites of parasites exclusive to specific species of fish. The autogenic component of the parasite fauna (40 species) dominated the allogenic component (21 species). The most likely explanation for the large number of fish parasites found at Celestún is the good environmental condition of the lagoon, which allows the completion of parasite life cycles and free circulation of euryhaline fishes from the marine environment bringing marine parasites into the lagoon.

  6. Helminth fauna of Lithobates brownorum (Anura: Ranidae at three localities in the state of Yucatán, Mexico Helmintofauna de Lithobates brownorum (Anura: Ranidae en tres localidades del estado de Yucatán, México

    Directory of Open Access Journals (Sweden)

    Carlos A. Yáñez-Arenas

    2010-04-01

    Full Text Available Between July 2004 and June 2005, 84 specimens of Lithobates brownorum (Sanders, 1973 were collected and examined for helminths. Hosts came from 3 localities in the state of Yucatán, Mexico: Celestún (n= 35, Lagunas de Yalahau (n= 33, and Ría Lagartos (n= 16. Twelve helminth taxa were found: 7 nematodes, 4 digeneans, and 1 acanthocephalan. With the exception of Haematoloechus floedae and Megalodiscus temperatus, all helminth taxa found have a Neotropical distribution. Our results differ from those obtained in previous studies dealing with amphibians in Mexico because we found higher richness and abundance of nematodes than digenean species. The relatively low mean intensity and mean abundance values reached by digenean species in this study may be related to the generalist host diet and with the vagility of frogs (from the aquatic to the terrestrial environment or vice versa.Entre julio del 2004 y junio del 2005, se recolectaron y examinaron 84 ejemplares de Lithobates brownorum (Sanders, 1973 en busca de helmintos en 3 localidades del estado de Yucatán: Celestún (n= 35, Lagunas de Yalahau (n= 33 y Ría Lagartos (n= 16. Los ejemplares estuvieron parasitados por 12 taxa de helmintos, 7 de nematodos, 4 digéneos y 1 acantocefalo. Con excepción de Haematoloechus floedae y Megalodiscus temperatus, todos los taxa presentan distribución neotropical. Nuestros resultados difieren de los obtenidos por otros autores que han reportado más especies de digéneos que de nematodos en este grupo de hospederos. Los bajos valores de intensidad y abundancia media de los digéneos encontrados en este estudio pueden estar relacionados con la amplia dieta del hospedero y la vagilidad que éste presenta entre el medio acuático y el terrestre.

  7. Methane fluxes from tropical coastal lagoons surrounded by mangroves, Yucatán, Mexico

    Science.gov (United States)

    Chuang, P.-C.; Young, M. B.; Dale, A. W.; Miller, L. G.; Herrera-Silveira, J. A.; Paytan, A.

    2017-05-01

    Methane concentrations in the water column and emissions to the atmosphere were determined for three tropical coastal lagoons surrounded by mangrove forests on the Yucatán Peninsula, Mexico. Surface water dissolved methane was sampled at different seasons over a period of 2 years in areas representing a wide range of salinities and anthropogenic impacts. The highest surface water methane concentrations (up to 8378 nM) were measured in a polluted canal associated with Terminos Lagoon. In Chelem Lagoon, methane concentrations were typically lower, except in the polluted harbor area (1796 nM). In the relatively pristine Celestún Lagoon, surface water methane concentrations ranged from 41 to 2551 nM. Methane concentrations were negatively correlated with salinity in Celestún, while in Chelem and Terminos high methane concentrations were associated with areas of known pollution inputs, irrespective of salinity. The diffusive methane flux from surface lagoon water to the atmosphere ranged from 0.0023 to 15 mmol CH4 m-2 d-1. Flux chamber measurements revealed that direct methane release as ebullition was up to 3 orders of magnitude greater than measured diffusive flux. Coastal mangrove lagoons may therefore be an important natural source of methane to the atmosphere despite their relatively high salinity. Pollution inputs are likely to substantially enhance this flux. Additional statistically rigorous data collected globally are needed to better consider methane fluxes from mangrove-surrounded coastal areas in response to sea level changes and anthropogenic pollution in order to refine projections of future atmospheric methane budgets.

  8. Analytical control of reducing agents on uranium/plutonium partitioning at purex process; Controle analitico dos agentes redutores na particao uranio/plutonio no processo purex

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Izilda da Cruz de

    1995-07-01

    Spectrophotometric methods for uranium (IV), hydrazine (N{sub 2}H{sub 4}) and its decomposition product hydrazoic acid(HN{sub 3}), and hydroxylamine (NH{sub 2} OH) determinations were developed aiming their applications for the process control of CELESTE I installation at IPEN/CNEN-SP. These compounds are normally present in the U/Pu partitioning phase of the spent nuclear treatment via PUREX process. The direct spectrophotometry was used for uranium (IV) analysis in nitric acid-hydrazine solutions based on the absorption measurement at 648 nm. The azomethine compound formed by reaction of hydrazine and p-dimethylamine benzaldehyde with maximum absorption at 457 nm was the basis for the specific analytical method for hydrazine determination. The hydrazoic acid analysis was performed indirectly by its conversion into ferric azide complex with maximum absorption at 465 nm. The hydroxylamine detection was accomplished based on its selective oxidation to nitrous acid which is easily analyzed by the reaction with Griess reagent. The resulted azocompound gas a maximum absorption at 520 nm. The sensibility of 1,4x10{sup -6}M for U(IV) with 0,8% of precision, 1,6x10{sup -6}M for hydrazine with 0,8% of precision, 2,3x10{sup -6}M hydrazoic acid with 0,9% of precision and 2,5x10{sup -6}M for hydroxylamine with 0,8% of precision were achieved. The interference studies have shown that each reducing agent can be determined in the presence of each other without any interference. Uranium(VI) and plutonium have also shown no interference in these analysis. The established methods were adapted to run inside glove-boxes by using an optical fiber colorimetry and applied to process control of the CELESTE I installation. The results pointed out that the methods are reliable and safety in order to provide just-in-time information about process conditions. (author)

  9. Preparation of high critical temperature YBa{sub 2}Cu{sub 3}O{sub 7} superconducting coatings by thermal spray; Elaboration par projection a chaud de revetements supraconducteurs a haute temperature critique de type YBa{sub 2}Cu{sub 3}O{sub 7}

    Energy Technology Data Exchange (ETDEWEB)

    Lacombe, Jacques

    1991-09-20

    The objective of this research thesis is the elaboration of YBa{sub 2}Cu{sub 3}O{sub 7} superconducting coatings by thermal spray. These coatings must have a high adherence, a high cohesion, and the best possible electrical characteristics. The author first briefly presents physical-chemical characteristics of this ceramic, and proposes a bibliographical synthesis on thick coatings prepared by thermal spray. In the next parts, he studies and describes conditions of elaboration of poly-granular coatings of YBa{sub 2}Cu{sub 3}O{sub 7}, and their structural and electric characteristics [French] Des revetements epais de YBa{sub 2}Cu{sub 3}O{sub 7} ont ete elabores par projection a chaud sur des substrats d'acier inoxydable revetus d'une sous-couche de Ni-Cr-Al-Y. Les principales etapes du processus de fabrication sont les suivantes: - preparation de la poudre par voie humide selon un procede mis au point au C.E.R.E.M., - realisation des revetements epais par projection a chaud de cette poudre selon trois differentes techniques: projection plasma atmospherique, projection plasma sous pression reduite, projection flamme oxyacetylenique. - traitement thermique en deux etapes des revetements pour recristalliser la phase YBa{sub 2}Cu{sub 3}O{sub 7} et la reoxygener (traitement thermique dans un four sous oxygene). Les depots elabores selon cette voie sont adherents et homogenes a la fois en composition et en morphologie. La phase supraconductrice YBa{sub 2}Cu{sub 3}O{sub 7} determinee par diffraction de rayons X est bien cristallisee; elle se presente sous forme de plaquettes d'environ 10 μm de long et 1 μm d'epaisseur sans orientation preferentielle. Les revetements realises par projection plasma atmospherique presentent les meilleures caracteristiques electriques: Tc(R=0) = 90.5K; ΔTc = 1K; ρ (300 K) = 0.7 - 0.8 mΩ.cm; Jc(77 K,0 T) = 1000 A/cm{sup 2}. Les proprietes d'ecrantage magnetique ont ete comparees a celles de materiaux utilises pour le blindage magnetique

  10. Determination of radioactive risks connected with the working of a nuclear plant; Evaluation des risques radioactifs lies au fonctionnement d'une installation nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Lavie, J M; Doury, A [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    Numerous problems which are posed by the evaluation of the radioactive risks linked to the working of a nuclear plant are new problems which have not yet been satisfactorily solved. In these conditions this study must be considered only as a preliminary approach whose essential aims are the following: - development and synthesis of the existing data; - rapid determination of conservative and usable orders of greatness for the security factors, both for normal working and in the case of an accident. The most probable typical accidents are reviewed together with the nature of the resulting risks and the principal factors on which these risks depend. Among these factors, one of the most important is atmospheric diffusion which is studied in some detail using the analytic model due to Sutton. A logical graphical presentation increasing the flexibility in the use of the results and presents the responsible authorities with a flexible, practical and rapid means of evaluating the risks involved starting from a sufficiently general system of initial and simultaneously valid conditions (types of accident, atmospheric conditions). (author) [French] De nombreux problemes souleves par l'evaluation des risques radioactifs lies au fonctionnement d'une installation nucleaire sont des problemes nouveaux qui n'ont pas encore recu de solution satisfaisante. Dans ces conditions cette etude ne doit etre consideree que comme une premiere approche dont les objectifs essentiels sont les suivants: - mise au point et synthese de donnees existantes; - determination rapide d'ordres de grandeur conservatifs et utilisables de valeurs de securite, tant en fonctionnement normal qu'en cas d'accident. Les accidents types les plus probables sont passes en revue ainsi que la nature des risques qui en decoulent et les principaux facteurs dont dependent ces risques. Parmi ces facteurs, l'un des plus importants est la diffusion atmospherique qui fait l'objet d'une etude particuliere a l'aide du modele

  11. Study of gases contained in an Antarctica glacier; Etude des gaz contenus dans un glacier antarctique

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-07-15

    This report presents a study of gases contained in ice samples taken from a drilling 97.8 meters deep in the coastal zone of Adelie Land (Antarctica). Simultaneously, a study has been made of the composition of the atmospheric air and of the gases extracted in situ from the firn. Carbon dioxyde was analysed by means of gas-phase chromatography and argon, oxygen and nitrogen by means of mass spectrometry. The results obtained show that for the most part the oxygen concentration decreases with an increase in the depth of the drilling. The values range from a maximum of 20,83 per cent of the volume at the surface to a minimum of 19,46 per cent of the volume at a depth of 87 meters. The results also show that the distribution of carbon dioxide concentration does not vary with the depth. These concentrations are either in the same range as or lower than the concentration of CO{sub 2} found in atmospheric air. The different results are discussed. (author) [French] Le present travail rend compte d'analyses de gaz contenus dans des echantillons de glace provenant d'un forage de 97,8 m de profondeur, realise dans la zone cotiere de la Terre Adelie (Antarctique). Parallelement, la composition d'air atmospherique et de gaz extraits in situ du neve a ete etudiee. La chromatographie en phase gazeuse a ete utilisee pour analyser le CO{sub 2} et la spectrometrie de masse pour analyser l'argon, l'oxygene et l'azote. Les resultats obtenus indiquent essentiellement le long du forage: - une decroissance de la teneur en oxygene avec la profondeur, les valeurs extremes etant de 20.83 pour cent en volume a la surface et de 19,46 pour cent en volume a - 87 metres, - une repartition des teneurs en CO{sub 2} sans correlation nette avec la profondeur, ces teneurs etant de l'ordre ou inferieures a la teneur atmospherique. Les differents resultats sont discutes. (auteur)

  12. Contribution to the study of U-Ti and U-Pu-Ti carbides; Contribution a l'etude des carbures U-C-Ti et (U, Pu) - C-Ti

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-07-01

    After having discussed the reasons to use (U,Pu) carbides as fast reactor fuel, we examine the influence of the addition of titanium to these carbides. A preliminary study has been done on the system of U-C-Ti and some properties have been measured such as: density, thermal expansion, electrical resistivity, atmospheric corrosion and compatibility with stainless steel. The systems U-Pu-C-Ti (Pu/U + Pu equal to 15 per cent) and U-C-Ti have been found to be very similar. There exists a two phases region (U,Pu)C + TiC, an eutectic between (U,Pu)C and TiC for approximately 15 at %. The solubilities of U + Pu in TiC and of Ti in (U,Pu)C is less than 1 % at. The addition of titanium does not markedly change thermal expansion coefficients of (U,Pu)C. However the resistance to atmospheric corrosion and compatibility with stainless steel is improved. Thermal conductivity, calculated from electrical resistivity, has increased. On the other side, the density of fissile material is lowered. The combination of (U,Pu)C + TiC seems to be the most promising alloy for application as nuclear fuel. (author) [French] Apres avoir rappele les problemes poses par un combustible pour les reacteurs a neutrons rapides et l'interet des carbures U-Pu-C comme combustible, on examine l'influence de l'addition de titane dans ces carbures. Une etude preliminaire sur le systeme U-C-Ti a ete effectuee et quelques proprietes sont indiquees: densite, coefficients de dilatation, resistivite electrique, tenue a la corrosion atmospherique, compatibilite avec l'acier inoxydable. Le systeme U-Pu-C-Ti (Pu/U + Pu egal a 15 pour cent) presente de grandes analogies avec le systeme U-C-Ti. Il existe un domaine biphase (U,Pu)C + TiC, un eutectique entre (U,Pu)C et TiC pour environ 15 at % Ti; les solubilites de U + Pu clans TiC et de Ti dans (U,Pu)C sont inferieures a 1 at %. Par rapport a la phase (U,Pu)C, l'addition de titane est sans effets importants sur les coefficients de dilatation. Par contre la tenue a

  13. The Ability of MM5 to Simulate Ice Clouds: Systematic Comparison between Simulated and Measured Fluxes and Lidar/Radar Profiles at SIRTA Atmospheric Observatory

    Energy Technology Data Exchange (ETDEWEB)

    Chiriaco, M.; Vautard, R.; Chepfer, H.; Haeffelin, M.; Wanherdrick, Y.; Morille, Y.; Protat, A.; Dudhia, J.

    2005-03-18

    Ice clouds play a major role in the radiative energy budget of the Earth-atmosphere system (Liou 1986). Their radiative effect is governed primarily by the equilibrium between their albedo and greenhouse effects. Both macrophysical and microphysical properties of ice clouds regulate this equilibrium. For quantifying the effect of these clouds onto climate and weather systems, they must be properly characterized in atmospheric models. In this paper we use remote-sensing measurements from the SIRTA ground based atmospheric observatory (Site Instrumental de Recherche par Teledetection Atmospherique, http://sirta.lmd.polytechnique.fr). Lidar and radar observations taken over 18 months are used, in order to gain statistical confidence in the model evaluation. Along this period of time, 62 days are selected for study because they contain parts of ice clouds. We use the ''model to observations'' approach by simulating lidar and radar signals from MM5 outputs. Other more classical variables such as shortwave and longwave radiative fluxes are also used. Four microphysical schemes, among which that proposed by Reisner et al. (1998) with original or modified parameterizations of particle terminal fall velocities (Zurovac-Jevtic and Zhang 2003, Heymsfield and Donner 1990), and the simplified Dudhia (1989) scheme are evaluated in this study.

  14. Validation of a limited area model over Dome C, Antarctic Plateau, during winter

    Energy Technology Data Exchange (ETDEWEB)

    Gallee, Hubert; Gorodetskaya, Irina V. [Laboratoire de Glaciologie et de Geophysique de l' Environnement, CNRS, 54, rue Moliere, BP. 96, St Martin d' Heres Cedex (France)

    2010-01-15

    The limited area model MAR (Modele Atmospherique Regional) is validated over the Antarctic Plateau for the period 2004-2006, focussing on Dome C during the cold season. MAR simulations are made by initializing the model once and by forcing it through its lateral and top boundaries by the ECMWF operational analyses. Model outputs compare favourably with observations from automatic weather station (AWS), radiometers and atmospheric soundings. MAR is able to simulate the succession of cold and warm events which occur at Dome C during winter. Larger longwave downwelling fluxes (LWD) are responsible for higher surface air temperatures and weaker surface inversions during winter. Warm events are better simulated when the small Antarctic precipitating snow particles are taken into account in radiative transfer computations. MAR stratosphere cools during the cold season, with the coldest temperatures occurring in conjunction with warm events at the surface. The decrease of saturation specific humidity associated with these coldest temperatures is responsible for the formation of polar stratospheric clouds (PSCs) especially in August-September. PSCs then contribute to the surface warming by increasing the surface downwelling longwave flux. (orig.)

  15. Corrosion inhibition of magnesium heated in wet air, by surface fluoridation; Inhibition de la corrosion du magnesium chauffe dans l'air humide, par fluoruration superficielle

    Energy Technology Data Exchange (ETDEWEB)

    Caillat, R; Darras, R; Leclercq, D [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    The maximum temperature (350 deg. C) of magnesium corrosion resistance in wet air may be raised to 490-500 deg. C by the formation of a superficial fluoride film. This can be obtained by two different ways: either by addition of hydrofluoric acid to the corroding medium in a very small proportion such as 0,003 mg/litre; at atmospheric pressure, or by dipping the magnesium in a dilute aqueous solution of nitric and hydrofluoric acids at room temperature before exposing it to the corroding atmosphere. In both cases the corrosion inhibition is effective over a very long time, even several thousand hours. (author) [French] La temperature limite (350 deg. C) de resistance du magnesium a la corrosion par l'air humide, peut etre elevee jusque 490-500 deg. C par la formation d'une couche fluoruree superficielle. Deux procedes permettent d'obtenir ce resultat: l'atmosphere corrodante peut etre additionnee d'acide fluorhydrique a une concentration aussi faible que 0,003 mg/litre, a la pression atmospherique, ou bien le magnesium peut etre traite a froid, avant exposition a la corrosion, dans une solution aqueuse diluee d'acides nitrique et fluorhydrique. Dans les deux cas, la protection est assuree, meme pour de tres longues durees d'exposition: plusieurs milliers d'heures. (auteur)

  16. Oxidation films morphology; Sur la morphologie des pellicules d'oxydation

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    After studying the oxidation of several pure polyvalent metals (Fe, Cu, Mn, Ni, U) and of their oxides at high temperature and atmospheric pressure, the author suggests how to modify the usual representation of the oxide film (a piling of different oxide layers, homogeneous on a micrographic scale with a equi-axial crystallisation, free of mechanical tensions, with flat boundary surfaces) to have it nearer to reality. In this first part, the author exposes the study of the real micrographic structure of the oxidation film and gives examples of precipitation in the oxides during the cooling of the oxidised sample. (author) [French] En se basant sur les etudes qu'il a faites sur l'oxydation aux temperatures elevees et a la pression atmospherique de quelques metaux purs a valences multiples (Fe, Cu, Mn, Ni, U), et de leurs oxydes, l'auteur suggere comment le schema qui representerait la pellicule comme etant une superposition de diverses couches d'oxydes, homogenes micrographiquement, a cristallisations equiaxes, depourvues de tensions mecaniques et separees par des interfaces plans, doit etre modifie pour s'ajuster a la realite. Dans cette premiere partie, l'auteur etudie la structure micrographique reelle des pellicules d'oxydation et donne des exemples de precipitation dans les oxydes au cours du refroidissement des echantillons oxydes. (auteur)

  17. Oxidation films morphology; Sur la morphologie des pellicules d'oxydation

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    After studying the oxidation of several pure polyvalent metals (Fe, Cu, Mn, Ni, U) and of their oxides at high temperature and atmospheric pressure, the author suggests how to modify the usual representation of the oxide film (a piling of different oxide layers, homogeneous on a micrographic scale with a equi-axial crystallisation, free of mechanical tensions, with flat boundary surfaces) to have it nearer to reality. In this first part, the author exposes the study of the real micrographic structure of the oxidation film and gives examples of precipitation in the oxides during the cooling of the oxidised sample. (author) [French] En se basant sur les etudes qu'il a faites sur l'oxydation aux temperatures elevees et a la pression atmospherique de quelques metaux purs a valences multiples (Fe, Cu, Mn, Ni, U), et de leurs oxydes, l'auteur suggere comment le schema qui representerait la pellicule comme etant une superposition de diverses couches d'oxydes, homogenes micrographiquement, a cristallisations equiaxes, depourvues de tensions mecaniques et separees par des interfaces plans, doit etre modifie pour s'ajuster a la realite. Dans cette premiere partie, l'auteur etudie la structure micrographique reelle des pellicules d'oxydation et donne des exemples de precipitation dans les oxydes au cours du refroidissement des echantillons oxydes. (auteur)

  18. Liquid hydrogen and deuterium targets; Cibles a hydrogene et deuterium liquides

    Energy Technology Data Exchange (ETDEWEB)

    Bougon, M; Marquet, M; Prugne, P [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1961-07-01

    A description is given of 1) Atmospheric pressure target: liquid hydrogen, 400 mm thickness; thermal insulation: styrofoam; the hydrogen vapors are used to improve the target cooling; Mylar windows. 2) Vacuum target: 12 liter content: hydrogen or deuterium; liquid thickness 400 mm; thermal insulation is afforded by a vacuum vessel and a liquid nitrogen shield. Recovery and liquefaction of deuterium vapors are managed in the vacuum vessel which holds the target. The target emptying system is designed for operating in a few minutes. (author) [French] Description de: 1) Cible a pression atmospherique; hydrogene liquide, 400 mm d'epaisseur; l'isolement thermique: styrofoam; on utilise les vapeurs d'hydrogene pour ameliorer le refroidissement de la cible; hublots en Mylar. 2) Cible sous vide; contenance 12 litres; hydrogene ou deuterium; epaisseur du liquide 400 mm; l'isolement thermique est assure par une cuve a vide et un ecran d'azote liquide. Recuperation et liquefaction des vapeurs de deuterium sont effectuees dans la cuve a vide contenant la cible. Le systeme de vidange pour la cible est concu pour fonctionner en quelques minutes. (auteur)

  19. {alpha} counting device with pulse ionization chamber; Ensemble de comptage {alpha} a chambre d'ionisation a impulsion

    Energy Technology Data Exchange (ETDEWEB)

    Engelman, J; Guillon, H [Commissariat a l' Energie Atomique, Saclay(France). Centre d' Etudes Nucleaires

    1953-07-01

    This device has been achieved more especially in view of the control, by measure of activity {alpha}, of chemical separations. The sought-after features were the following: - simple handling; possibility to do some measures fast and frequent. It imposed the choice of an ionization chamber at air pressure; - possibility to count {alpha} in presence of a continuous {beta} background noise, which imposed a resolution time as short as possible; - absence of micro-phonics, which imposed a study of suspension of the room; - great safety of use. (author) [French] Cet appareil a ete realise plus particulierement en vue du controle, par mesure d'activite {alpha}, de separations chimiques. Les caracteristiques recherchees etaient les suivantes: - maniement simple; possibilite d'effectuer des mesures rapides et frequentes. Cela imposait le choix d'une chambre d'ionisation a air a pression atmospherique; - possibilite de compter des {alpha} en presence d'un fond continu de {beta}, ce qui imposait un temps de resolution aussi court que possible; - absence de microphonie, ce qui demandait une etude du mode de suspension de la chambre; - grande securite de fonctionnement. (auteur)

  20. Temperature setting and thermal regulation system for liquid hydrogen bubble chamber; Systeme de mise en temperature et de regulation thermique de chambres a bulles a hydrogene liquide

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, J; Prugne, P; Roubeau, P [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1961-07-01

    Hydrogen bubble chamber cooling and constant temperature maintenance in the 25/28 deg. K, range by means of liquid hydrogen boiling under atmospheric pressure (20.4 deg. K) need a device, if possible automatic allowing the introduction of a variable amount of cold to counterbalance the heat transfer either static or due to the chamber operation. A variable impedance heat exchanger has been designed, built and experimented for this purpose. This device, which takes little space (less than 1000 cm{sup 3}) allows transfer of a variable cold power between 0 and 500 watts (0 to 50 liter of evaporated hydrogen). (author) [French] Pour le refroidissement des chambres a bulles a hydrogene et pour le maintien d'une temperature constante dans la gamme 25/28 deg. K au moyen d'hydrogene a l'ebullition sous pression atmospherique (20,4 deg. K), on a besoin d'un dispositif, si possible automatique, permettant l'introduction d'une quantite variable de froid pour compenser le transfert de chaleur, soit statique, soit du a l'operation de la chambre. Un echangeur de chaleur a impedance variable a ete concu, construit et essaye pour cet usage. Ce dispositif qui est peu encombrant (en dessous de 1000 cm{sup 3} ) permet le transfert d'une puissance frigorifique, variable entre 0 et 500 watts (0 a 50 litres d'hydrogene evapore). (auteur)

  1. Evaluation of the MOCAGE Chemistry Transport Model during the ICARTT/ITOP Experiment

    Science.gov (United States)

    Bousserez, N.; Attie, J. L.; Peuch, V. H.; Michou, M.; Pfister, G.; Edwards, D.; Emmons, L.; Arnold, S.; Heckel, A.; Richter, A.; hide

    2007-01-01

    We evaluate the Meteo-France global chemistry transport 3D model MOCAGE (MOdele de Chimie Atmospherique a Grande Echelle) using the important set of aircraft measurements collected during the ICARRT/ITOP experiment. This experiment took place between US and Europe during summer 2004 (July 15-August 15). Four aircraft were involved in this experiment providing a wealth of chemical data in a large area including the North East of US and western Europe. The model outputs are compared to the following species of which concentration is measured by the aircraft: OH, H2O2, CO, NO, NO2, PAN, HNO3, isoprene, ethane, HCHO and O3. Moreover, to complete this evaluation at larger scale, we used also satellite data such as SCIAMACHY NO2 and MOPITT CO. Interestingly, the comprehensive dataset allowed us to evaluate separately the model representation of emissions, transport and chemical processes. Using a daily emission source of biomass burning, we obtain a very good agreement for CO while the evaluation of NO2 points out incertainties resulting from inaccurate ratio of emission factors of NOx/CO. Moreover, the chemical behavior of O3 is satisfactory as discussed in the paper.

  2. GREENGRASS. Sources and sinks of greenhouse gases from managed European grasslands and mitigation strategies. Final Project Report

    Energy Technology Data Exchange (ETDEWEB)

    Soussana, J.F. [Institut National de la Recherche Agronomique INRA Clermont-Ferrand, 63122 Saint-Genes-Champanelle (FR)] (and others)

    2005-03-15

    In support of the European post-Kyoto policy, the GREENGRASS project will measure the net global warming potential resulting from the exchange of CO2, N2O and Twitch managed European grasslands and assess the European wide mitigation potential of key field and farm management scenarios. Long-term micrometeorological measurements at sites in a European wide network will be complemented by experimental assessment of the effects of management options bonnet fluxes. The results will be used to refine emission factors used in national inventories and to evaluate farm-level mitigation scenarios with respect to tenet global warming potential associated to grassland management. These evaluations will be conducted at the field and farm level, and by upscaling simulation results to the Europe scale. (Contributions by Risoe National Laboratory (Denmark), INRA Clermont Ferrand (France), INRA Grignon (France), INRA Dijon (France), Institut de l'Elevage Angers (France), LSCE Gif-sur-Yvette (France), Cetre Interprofessionel Technique d'Etudes de la Pollution Atmospherique (France), Forest Research Institute (Hungary), Szent Istvan University (Hungary), Eoetvoes Lorand University Elte (Hungary), Trinity College of Dublin (Ireland), Istituto di Biometeorologia (IBIMET) del Consiglio Nazionale delle Ricerche (Italy), University of Tuscia (Italy), Energy research Centre of the Netherlands ECN (Netherlands), Wageningen University (Netherlands), Plant Research International (Netherlands), Centre of Ecology and Hydrology (United Kingdom), Scottish Agricultural College (Scotland), University of Aberdeen (Scotland), Federal Research Station for Agroecology and Agriculture (Switzerland))

  3. The elimination as radioactive waste of a fluorination furnace from the plutonium extraction plant (1962); Elimination comme dechet radioactif d'un four de fluoration en provenance de l'usine d'extraction du plutonium (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Boutot, P; Capitaine, A; Giachetto, L [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1961-07-01

    The furnace, 1.60 x 0. 75 x 0.80 m in dimensions, was placed inside a 2. 50 x 1.25 x 2 m glove box. The operations were as follows: - removal of the furnace from the glove box; - storage of the furnace in a special container ; - reduction to a minimum volume and elimination of the glove box. A very high {alpha} activity, oxidation of the various channeling, and waste products trapped in the box necessitated special safety measures such as fixing of the contamination, crushing, the use of appropriate vinyl envelopes. This long and tedious work was carried out with no resulting bodily or atmospheric contamination. (authors) [French] Le four de 1,60 x 0,75 x 0,80 m, etait place dans une boite a gants de 2,50 x 1,25 x 2 m. L'operation a consiste: - a extraire le four de la boite a gants; - a le stocker dans un container special; - a reduire a un volume minimum la boite a gants pour l'eliminer. Une activite {alpha} tres elevee, l'oxydation des differentes canalisations, les dechets occlus dans la boite ont exige des moyens de protection speciaux tels que l'encollage de la contamination, la mise en depression, l'emploi d'enveloppes de vinyle appropriees. Ce travail, long et fastidieux, a ete effectue sans entrainer de contamination corporelle ou atmospherique. (auteurs)

  4. Corrosion inhibition of magnesium heated in wet air, by surface fluoridation; Inhibition de la corrosion du magnesium chauffe dans l'air humide, par fluoruration superficielle

    Energy Technology Data Exchange (ETDEWEB)

    Caillat, R.; Darras, R.; Leclercq, D. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    The maximum temperature (350 deg. C) of magnesium corrosion resistance in wet air may be raised to 490-500 deg. C by the formation of a superficial fluoride film. This can be obtained by two different ways: either by addition of hydrofluoric acid to the corroding medium in a very small proportion such as 0,003 mg/litre; at atmospheric pressure, or by dipping the magnesium in a dilute aqueous solution of nitric and hydrofluoric acids at room temperature before exposing it to the corroding atmosphere. In both cases the corrosion inhibition is effective over a very long time, even several thousand hours. (author) [French] La temperature limite (350 deg. C) de resistance du magnesium a la corrosion par l'air humide, peut etre elevee jusque 490-500 deg. C par la formation d'une couche fluoruree superficielle. Deux procedes permettent d'obtenir ce resultat: l'atmosphere corrodante peut etre additionnee d'acide fluorhydrique a une concentration aussi faible que 0,003 mg/litre, a la pression atmospherique, ou bien le magnesium peut etre traite a froid, avant exposition a la corrosion, dans une solution aqueuse diluee d'acides nitrique et fluorhydrique. Dans les deux cas, la protection est assuree, meme pour de tres longues durees d'exposition: plusieurs milliers d'heures. (auteur)

  5. Tritium means of detection and of protection; Le tritium moyens de detection et de protection

    Energy Technology Data Exchange (ETDEWEB)

    Sutra-Fourcade, Y [Commissariat a l' Energie Atomique, Marcoule (France). Centre d' Etudes Nucleaires

    1967-07-01

    The report is an attempt to correlate present data concerning tritium, especially from the health physics points of view. The various detection and measurement methods are reviewed in turn: measurement of tritium in the atmosphere, in liquids and on surfaces. The operation of various types of apparatus is analyzed and the sensitivity limits deduced from laboratory tests are given. Otter sections are devoted to the means of protection which can be used against inhalation of tritium (ventilation, protective clothing) and to calculations of the changes in atmospheric pollution in a given place and of the time spent in a contaminated zone. The last part deals with the decontamination of equipment contaminated with tritium. (author) [French] Le rapport represente un essai de synthese des connaissances actuelles sur le tritium, essentiellement du point de vue de la radioprotection. Les differents moyens de detection et de mesure sont successivement passes en revue: mesure du tritium dans l'atmosphere, dans les liquides, sur les surfaces. Le fonctionnement de differents types d'appareils est analyse et les limites de sensibilite sont donnees d'apres les essais effectues en laboratoire. D'autres paragraphes sont consacres aux moyens de protection contre l'inhalation du tritium (ventilation, vetements de protection), a des calculs d'evolution de pollution atmospherique dans les locaux et de temps de presence en atmosphere contaminee. La derniere partie se rapporte a la de contamination de materiel contamine par du tritium. (auteur)

  6. Integrator drawer with pre-adjusted time for the study of decay of very low activity sources; Tiroir integrateur a temps preregle pour l'etude de decroissance des sources de tres faible activite

    Energy Technology Data Exchange (ETDEWEB)

    Couly, J. P.

    1962-07-01

    The author presents a drawer which can be adapted on standard counting assemblies to control the decay of very low activity sources such as samples aimed at atmospheric control. The operation principle relies on charging a tank capacitor with pulses received from a sensor. The resulting voltage is measured by a high input resistance circuit, and then recorded. The tank capacitor is periodically discharged by pulses from a time base circuit. The recording appears under the form of rays. Their length corresponds to the counting rate and the extremity envelope represents the source activity decay curve as a function of time [French] Ce tiroir, pouvant s'adapter sur les ensembles de comptage standards, permet de suivre la decroissance de sources radioactives de tres faible activite (de l'ordre de 10{sup -9} curie) tels que les prelevements de controle atmospherique. Le principe de fonctionnement consiste a charger un condensateur reservoir avec les impulsions recues du detecteur, et prealablement mises en forme. La tension resultante est mesuree par un circuit a grande resistance d'entree puis enregistree a l'aide d'un enregistreur MECI monovoie. Le condensateur reservoir est decharge periodiquement par des impulsions provenant d'un circuit de base de temps. L'enregistrement apparait sous la forme de traits, leur longueur correspond au taux de comptage et l'enveloppe de leur extremite represente la courbe de decroissance de l'activite de la source en fonction du temps. (auteur)

  7. Annual Greenland Accumulation Rates (2009-2012) from Airborne Snow Radar

    Science.gov (United States)

    Koenig, Lora S.; Ivanoff, Alvaro; Alexander, Patrick M.; MacGregor, Joseph A.; Fettweis, Xavier; Panzer, Ben; Paden, John D.; Forster, Richard R.; Das, Indrani; McConnell, Joseph R.; hide

    2016-01-01

    Contemporary climate warming over the Arctic is accelerating mass loss from the Greenland Ice Sheet through increasing surface melt, emphasizing the need to closely monitor its surface mass balance in order to improve sea-level rise predictions. Snow accumulation is the largest component of the ice sheet's surface mass balance, but in situ observations thereof are inherently sparse and models are difficult to evaluate at large scales. Here, we quantify recent Greenland accumulation rates using ultra-wideband (2-6.5 gigahertz) airborne snow radar data collected as part of NASA's Operation IceBridge between 2009 and 2012. We use a semi-automated method to trace the observed radiostratigraphy and then derive annual net accumulation rates for 2009-2012. The uncertainty in these radar-derived accumulation rates is on average 14 percent. A comparison of the radarderived accumulation rates and contemporaneous ice cores shows that snow radar captures both the annual and longterm mean accumulation rate accurately. A comparison with outputs from a regional climate model (MAR - Modele Atmospherique Regional for Greenland and vicinity) shows that this model matches radar-derived accumulation rates in the ice sheet interior but produces higher values over southeastern Greenland. Our results demonstrate that snow radar can efficiently and accurately map patterns of snow accumulation across an ice sheet and that it is valuable for evaluating the accuracy of surface mass balance models.

  8. Formation and evolution of aerosols in filtered air and in natural air. Effect of radioactivity; Formation et evolution des aerosols dans l'air filtre et dans l'air naturel action de la radioactivite

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-06-01

    Results are presented concerning the formation, the evolution, the coagulation and the electrical charge of aerosols which form in natural filtered air containing only gaseous impurities, under the influence of solar light (photolysis) and of radioactive disintegrations (radiolysis). The modifications brought about in the aerosol by an increase in the sulphur dioxide content and in the natural radioactive gas content are studied. The work is then repeated with non-filtered natural atmospheric air. A comparison is also made of the behaviour of non-radioactive and radioactive particles (active thoron deposit). In conclusion, the possible consequences of these phenomena on the origin and the size distribution of particles occurring in the atmosphere is considered. (author) [French] On expose les resultats obtenus sur la formation, l'evolution, la coagulation et la charge electrique des aerosols qui se forment dans l'air naturel filtre, ne contenant que des impuretes gazeuses, sous l'influence de la lumiere solaire (photolyse) et des desintegrations radioactives (radiolyse). On examine les modifications apportees a l'aerosol forme par l'augmentation de la teneur de l'air en anhydride sulfureux et en gaz radioactif naturel. Cette etude est ensuite reprise mais avec de l'air naturel atmospherique non filtre. On compare egalement le comportement des particules non radioactives et radioactives (depot actif du thoron). En conclusion, on examine les consequences que peuvent avoir ces phenomenes sur l'origine et la granulometrie des particules contenues dans l'atmosphere. (auteur)

  9. Heterobothrium lamothei n. sp. (Monogenea: Diclidophoridae from the gills of Sphoeroides testudineus (Pisces: Tetraodontidae from the coast of Yucatán, Mexico Heterobothrium lamothei n. sp. (Monogenea: Diclidophoridae de las branquias de Sphoeroides testudineus (Pisces: Tetraodontidae de la costa de Yucatán, México

    Directory of Open Access Journals (Sweden)

    Víctor M. Vidal-Martínez

    2008-08-01

    Full Text Available The presence of a member of the genus Heterobothrium is described for the first time from the coast of Yucatán Peninsula, southeastern Mexico. Heterobothrium lamothei n. sp. is recorded parasitizing the gills of the tetraodontid fish Sphoeroides testudineus (Linnaeus, 1758 from 4 coastal lagoons in Yucatán: Celestún (20° 52' N, 90° 24' W, Chelem (21°15'N89°45'W, Dzilam (21°35'N 88°35'W and Río Lagartos (21°22'N 87°30'W. The new species differs from the other species described in the genus, by a combination of characters including a copulatory organ armed with 12-15 genital hooks, the distal pair of clamps smaller in comparison with the 3 other pairs and by having 15-26 testes. The infection parameters were for Celestun, 47 % of prevalence, number of fish examined (n = 47, mean abundance of 1.76 ± 9.62; Chelem, 20 % (n = 30, 0.53 ± 8.48; Dzilam, 2 % (n = 60, 0.02 ± 0.00; Río Lagartos, 25 % (n = 59, 0.34 ± 1.58. Heterobothrium lamothei n. sp. may be considered as potentially dangerous species for the aquaculture of S. testudineus due to its direct life cycle hat high fish densities would increase the transmission of this monogenean.Se registra por primera vez la presencia de un miembro del género Heterobothrium en la costa de la península de Yucatán, México: Heterobothrium lamothei n. sp., parásito de las branquias del pez tetraodóntido Sphoeroides testudineus (Linnaeus, 1758 en 4 lagunas costeras de Yucatán: Celestún (20° 52' N, 90° 24' O, Chelem (21°15'N89°45'O, Dzilam (21°35'N 88°35'O y Río Lagartos (21°22'N 87°30'O. La especie nueva difiere de otras del género por un conjunto de características que incluyen un órgano copulador con 12 a 15 ganchos genitales, un par distal de pinzas más pequeño que los 3 pares superiores y un número reducido de testículos (15-26. Los parámetros de infección para las 4 localidades fueron: Celestún: 47 % de prevalencia, 47 peces examinados (n = 47, abundancia media de 1

  10. Infrared Lunar Laser Ranging at Calern : Impact on Lunar Dynamics

    Science.gov (United States)

    Viswanathan, Vishnu; Fienga, Agnes; Manche, Herve; Gastineau, Mickael; Courde, Clement; Torre, Jean Marie; Exertier, Pierre; Laskar, Jacques

    2017-04-01

    Introduction: Since 2015, in addition to the traditional green (532nm), infrared (1064nm) has been the preferred wavelength for lunar laser ranging at the Calern lunar laser ranging (LLR) site in France. Due to the better atmospheric transmission of IR with respect to Green, nearly 3 times the number of normal points have been obtained in IR than in Green [1]. Dataset: In our study, in addition to the historical data obtained from various other LLR sites, we include the recent IR normal points obtained from Calern over the 1 year time span (2015-2016), constituting about 4.2% of data spread over 46 years of LLR. Near even distribution of data provided by IR on both the spatial and temporal domain, helps us to improve constraints on the internal structure of the Moon modeled within the planetary ephemeris : INPOP [2]. Data reduction: IERS recommended models have been used in the data reduction software GINS (GRGS,CNES) [3]. Constraints provided by GRAIL [4], on the Lunar gravitational potential and Love numbers have been taken into account in the least-square fit procedure. Earth orientation parameters from KEOF series have been used as per a recent study [5]. Results: New estimates on the dynamical parameters of the lunar core will be presented. Acknowledgements: We thank the lunar laser ranging observers at Observatoire de la Côte d'Azur, France, McDonald Observatory, Texas, Haleakala Observatory, Hawaii, and Apache Point Observatory in New Mexico for providing LLR observations that made this study possible. The research described in this abstract was carried out at Geoazur-CNRS, France, as a part of a PhD thesis funded by Observatoire de Paris and French Ministry of Education and Research. References: [1] Clement C. et al. (2016) submitted to A&A [2] Fienga A. et al. (2015) Celest Mech Dyn Astr, 123: 325. doi:10.1007/s10569-015-9639-y [3] Viswanathan V. et al. (2015) EGU, Abstract 18, 13995 [4] Konopliv A. S. et al. (2013) J. Geophys. Res. Planets, 118, 1415

  11. A Introdução de Astronomia Básica para Estudantes de 5 e 6 Séries do Ensino Fundamental

    Science.gov (United States)

    Gonzaga, E. P.; Voelzke, M. R.

    2008-09-01

    Com intuito de despertar o interesse pelo estudo da astronomia, desenvolveu-se entre 2003 e 2006 no Centro Educacional do Serviço Social da Indústria situado no município de Mauá, São Paulo, um trabalho com duração de 12 meses para turmas de 11 e 12 anos, sendo três turmas por período (2003 / 2004, 2004 / 2005 e 2005 / 2006). O trabalho realizado, objetivando a introdução da astronomia básica com observações de constelações e das fases da Lua, permitindo estender-se a outros corpos celestes, iniciou-se com visita ao planetário Mundo Estelar, localizado no Ipiranga, São Paulo levantou-se a questão da importância do estudo da astronomia e foi lançado aos estudantes um trabalho de observação, com a proposta de localizar as constelações e compreender as fases da Lua, para o registro de tais observações, foram distribuídos mapas celestes, pastas, planilhas de anotações com lacunas para, constelações, fases da Lua e relatos, onde os estudantes acrescentaram pesquisas e relatórios. Os resultados dos 346 estudantes foram que 86,7% (300) concluíram a etapa de observação, destes 300 estudantes 43,3% (130) pesquisaram sobre as constelações e 19,0% (57) localizaram até quatro constelações. Dos 346 estudantes, 44,2% (153) registraram as fases da Lua equivocadamente e 10,4% (36) anexaram reportagens sobre astronomia. Conclui-se que os estudantes se dividiram em pesquisadores, sendo os estudantes que registraram e anexaram informações e, os observadores que preencheram as planilhas de observações, além de desenvolverem habilidades e competências relacionadas ao estudo da astronomia.

  12. Qualidade fisiológica de sementes de soja convencional e transgênica RR produzidas sob aplicação foliar de manganês

    Directory of Open Access Journals (Sweden)

    Everson Reis Carvalho

    2014-09-01

    Full Text Available Sementes de soja com alta qualidade fisiológica são essenciais à obtenção de produtividade elevada e um dos fatores que afetam a produção de sementes é a nutrição mineral. O objetivo neste trabalho foi avaliar o efeito da aplicação foliar de manganês, em diferentes doses e estádios de aplicação, na qualidade fisiológica de sementes de soja, em cultivares convencionais e em suas derivadas transgênicas RR, com distintos teores de lignina do tegumento. O ensaio foi conduzido em blocos casualizados, com três repetições e esquema fatorial 4 x 4 x 2, sendo quatro cultivares de soja, duas convencionais e suas derivadas transgênicas RR (BRS Celeste e BRS Baliza RR; BRSGO Jataí e BRS Silvânia RR, quatro doses de Mn via foliar (0; 200; 400 e 600 g Mn ha-1 e dois estádios de aplicação (R1 e R3. A qualidade fisiológica das sementes foi estimada, antes e após seis meses de armazenamento, por meio dos testes: Germinação, Envelhecimento acelerado, Emergência de plântulas, Condutividade elétrica e Tetrazólio (Viabilidade, vigor e danos mecânicos. Realizou-se também a quantificação de lignina no tegumento das sementes. A aplicação foliar de Mn proporciona incrementos na qualidade fisiológica nas sementes de soja produzidas. Sementes das cultivares de soja Celeste e Baliza RR apresentam melhor qualidade fisiológica quando comparadas às de Jataí e Silvânia RR. Sementes de cultivares de soja com maior teor de lignina no tegumento não apresentam necessariamente melhor qualidade fisiológica, sendo a qualidade das sementes relacionada a outros fatores intrínsecos ao genótipo.

  13. A Reappraising of Cosmography: the Interface Between Astronomical and Geographic Studies. (Breton Title: Releitura do Conceito de Cosmografia: a Interface Entre os Estudos Astronômicos e Geográficos.) Una Relectura del Concepto de Cosmografía: la Interfase Entre los Estudios Astronómicos y Geográficos

    Science.gov (United States)

    Azevedo Sobreira, Paulo Henrique

    2012-12-01

    The concept of "Cosmography" is in disuse since the 80s of the last century, but the astronomical themes previously discussed in the school subjects of Geography and Cosmography remain in current textbooks. The use of term "Cosmography" was rescued in this research, and the study of its re-signification prompted the appearance of the term Geographic Cosmography. The Geographic Cosmography is a field of studies of the Geography, whose set of knowledge and skills is predominantly scholar. It studies the interface between terrestrial and celestial knowledge, and assigns a geographic significance to them. It examines human and natural relationships with Sidereal Space and its consequences for society and nature. O conceito de "Cosmografia" está em desuso desde os anos 80 do século XX, mas os temas astronômicos anteriormente abordados nas disciplinas escolares de Cosmografia e de Geografia permanecem nos atuais livros didáticos. O uso do termo "Cosmografia" foi resgatado nesta pesquisa e o estudo de sua ressignificação proporcionou o surgimento do termo Cosmografia Geográfica. A Cosmografia Geográfica é um campo de estudos da Geografia, cujo conjunto de conhecimentos e habilidades é predominantemente escolar. Estuda a interface entre os conhecimentos terrestres e os celestes e lhes atribui significância geográfica. Analisa as relações humanas e naturais com o Espaço Sideral e suas consequências para a sociedade e a natureza. Aunque el concepto de "Cosmografía" no se usa desde la década de los '80 del siglo pasado, los temas astronómicos que se enseñaban anteriormente en las asignaturas escolares de Cosmografía y de Geografía permanecen en los actuales libros didácticos. El uso del término "Cosmografía" fue rescatado en esta investigación y el estudio de su resignificación proporcionó el surgimiento del término Cosmografía Geográfica. La Cosmografía Geográfica es un campo de estudio de la Geografía, donde el conjunto de conocimientos y

  14. Actualización de la distribución de especies del género Haemagogus (Díptera: Culicidae en la Región Caribe colombiana

    Directory of Open Access Journals (Sweden)

    Ronald Maestre-Serrano

    2013-08-01

    Full Text Available Introducción. Los mosquitos del género Haemagogus son importantes en salud pública, porque algunas de sus especies han sido involucradas como vectores del virus de la fiebre amarilla en su ciclo selvático. Objetivo. Actualizar la distribución de especies del género Haemagogus en las áreas urbanas y periurbanas de los departamentos de Atlántico y Sucre de la Región Caribe. Materiales y métodos. El material entomológico se recolectó mediante larvitrampas en los departamentos de Atlántico y Sucre, durante los años 2010 y 2011. El 80 % de los ejemplares inmaduros se preservó en alcohol al 70 %; algunos se mantuvieron vivos para obtener series entomológicas. La determinación taxonómica se hizo con las claves y descripciones de Arnell (1973. Resultados. En Atlántico, 2,32 % (871 de los 37.573 Culicidae inmaduros eran larvas del género Haemagogus. En Sucre se recolectaron 44 larvas del mismo género (1,22 % de los 3. 611 culícidos. Las especies del género Haemagogus fueron determinadas o identificadas como Hg. equinus, Hg.anastasionis y Hg. celeste en ambos departamentos. En los dos, la mayor abundancia de especies del género Haemagogus se registró durante los meses de mayor precipitación, de junio a noviembre. Conclusión. Se registra la presencia de Hg. anastasionis, Hg. celeste y Hg. equinus en recipientes artificiales en áreas urbanas y periurbanas de los departamentos de Atlántico y Sucre, y se amplía su distribución en la Región Caribe colombiana.   doi: http://dx.doi.org/10.7705/biomedica.v33i0.706

  15. Radioastronomía: Una Mirada Más Amplia

    Science.gov (United States)

    Bianchi, Viviana

    2004-12-01

    The existence of the celestial bodies is known due to the light they emit. But light is a small part of a bigger phenomenon known as electromagnetic radiation. The representation of all kinds of electromagnetic radiation as a function of its frequency is called the electromagnetic spectrum. If we only studied the visible part of the spectrum, we would ignore a great deal of information. The celestial bodies emit radiation in all the regions of the electromagnetic spectrum, with very different intensity. To capture these data, astronomers design new types of telescopes that capture radiation at different wavelengths, among them the radiotelescopes that, as the name indicates, detect radio waves. The radiotelescope can be compared to a regular radio set. A radio station sends information by means of radio waves. The radio set captures these waves by means of its antenna, processes it and reproduces the information (music, etc.) in audible form. In the field of radioastronomy, interesting observations can be carried out: radio emission from stars, nebulas, pulsars, distant galaxies and stars, radiogalaxies, the Milky Way, the Sun, Jupiter, etc. La presencia de los cuerpos celestes se conoce gracias a que emiten luz. Pero la luz constituye solo una pequeña parte de un fenómeno mucho mas amplio conocido como radiación electromagnética. La representación de todas las clases de radiación como función de su frecuencia se denomina espectro electromagnético. Si solo estudiáramos la parte visual del espectro ignoraríamos una gran cantidad de información. Los cuerpos celestes emiten radiación en todas las regiones del espectro electromagnético, aunque con muy distinta intensidad. Para captar estos datos, los astrónomos deben diseñar nuevos tipos de telescopios que puedan captar la radiación de distintas longitudes de ondas, entre ellos los radiotelescopios, qué como su nombre lo indica detectan ondas de radio. El radiotelescopio puede compararse a un aparato

  16. Forecasting of development of acute poisonings in agricultural workers while using combined formulations based on difenoconazole

    Directory of Open Access Journals (Sweden)

    Stavnichenko P.V.

    2017-10-01

    Full Text Available In the general structure of occupational diseases, a large proportion belongs to acute poisoning with pesticides (mainly group cases. However, today it is impossible to drop the use of pesticides in agriculture. Their application ensures high biological and economic efficiency of the latter, reduces losses of the yield. The purpose of the work was to predict the possibility of acute toxic effects in agricultural workers when working with combined formulations based on difenoconazole. Materials and methods. To assess the influence on the organism of the workers of the above-mentioned substances and formulations on their basis, the coefficient of inhalation poisoning possibility (CIPP, the coefficient of selective action of the pesticide in inhalation effect (CSAing and the selective action of the pesticide in the dermal effect (CSAderm were calculated. Results. Calculated values of CSAing (103.4-4701.2 and CSAderm (237.4-12345.7 for all investigated active substances were more than 100, this indicates to a rather high selectivity of their action. By the CSAing value formulations Celeste Top, Celeste Trio, Dinali, Cydeli Top belong to pesticides with a relatively low selectivity of action when they are inhaled by workers in the process of crops treating, the remaining formulations have a sufficient selectivity of action in inhalation intake. In addition, it should be noted that in general, for all combined preparations CSA values are significantly lower than for separate active ingredients, in addition to the above assumption, can be explained by the presence of other formulants in the preparation that may have not significant but toxic effect on the body of workers. All investigated substances in the probability of occurrence of acute poisoning with the use of combined preparations on their basis are related to the 4th grade of danger according to State Standards 8.8.1.002-98. There was proved relative safety in case of penetration into the

  17. An Ethnomathematics Exercise for Analyzing a Khipu Sample from Pachacamac (Perú

    Directory of Open Access Journals (Sweden)

    Alberto Saez-Rodríguez

    2012-01-01

    Full Text Available Una muestra de quipu estudiada por Gary Urton comporta una división por cuadrantes poco común. Utilizando dicho hallazgo de Urton, podemos visualizar la información contenida en los pares de cuadrantes,la cual está determinada por una distribución de nudos con orientaciones opuestas de 'S' y de 'Z', brindándonos, así, toda la información necesaria para identificar las coordenadas celestes de las estrellas másbrillantes del cúmulo de las Pléyades. En el presente estudio se usa el análisis de la Regresión Lineal con el fin de construir un modelo que permita predecir el comportamiento de la variable dependiente y (valores de los nudos con orientación de 'Z' en función de la variable independiente x (valores de los nudos con orientación de 'S'. Dicho modelo se logró usando un diagrama de dispersión, lo que nos condujo a un mapa con la posición de las siete estrellas más brillantes de las Pléyades, como un modelo empírico de la relación que mantienen las variables en estudio.

  18. Post-storage cell wall metabolism in two sweet cherry (Prunus avium L.) cultivars displaying different postharvest performance.

    Science.gov (United States)

    Belge, Burcu; Comabella, Eva; Graell, Jordi; Lara, Isabel

    2015-09-01

    The biochemical processes underlying firmness loss of sweet cherry (Prunus avium L.) fruit are poorly understood. Studies on cell wall metabolism of sweet cherry have been generally undertaken during on-tree development or at harvest maturity, while published reports on postharvest changes are scarce and fragmentary. In this work, cell wall modifications after storage at 0 ℃ were studied in two cherry cultivars ('Celeste' and 'Somerset') displaying different postharvest potential. Firmness was largely determined by the yields of the Na2CO3- and KOH-soluble fractions, enriched in covalently-bound pectins and in matrix glycans, respectively, and correlated well with ascorbic acid contents. The yields of these two cell wall fractions were correlated inversely with pectinmethylesterase and endo-1,4-β-d-glucanase activities, indicating a relevant role of these two enzymes in postharvest firmness changes in sweet cherry. The amount of solubilised cell wall materials was closely associated to the contents of dehydroascorbic acid, suggesting the possible involvement of oxidative mechanisms in cell wall disassembly. These data may help understanding the evolution of fruit quality during the marketing period, and give hints for the design of suitable management strategies to preserve key attributes. © The Author(s) 2014.

  19. Profiles of environmental contaminants in hawksbill turtle egg yolks reflect local to distant pollution sources among nesting beaches in the Yucatán Peninsula, Mexico.

    Science.gov (United States)

    Muñoz, Cynthia C; Vermeiren, Peter

    2018-04-01

    Knowledge of spatial variation in pollutant profiles among sea turtle nesting locations is limited. This poses challenges in identifying processes shaping this variability and sets constraints to the conservation management of sea turtles and their use as biomonitoring tools for environmental pollutants. We aimed to increase understanding of the spatial variation in polycyclic aromatic hydrocarbon (PAH), organochlorine pesticide (OCP) and polychlorinated biphenyl (PCB) compounds among nesting beaches. We link the spatial variation to turtle migration patterns and the persistence of these pollutants. Specifically, using gas chromatography, we confirmed maternal transfer of a large number of compounds (n = 68 out of 69) among 104 eggs collected from 21 nests across three nesting beaches within the Yucatán Peninsula, one of the world's most important rookeries for hawksbill turtles (Eretmochelys imbricata). High variation in PAH profiles was observed among beaches, using multivariate correspondence analysis and univariate Peto-Prentice tests, reflecting local acquisition during recent migration movements. Diagnostic PAH ratios reflected petrogenic origins in Celestún, the beach closest to petroleum industries in the Gulf of Mexico. By contrast, pollution profiles of OCPs and PCBs showed high similarity among beaches, reflecting the long-term accumulation of these pollutants at regional scales. Therefore, spatial planning of protected areas and the use of turtle eggs in biomonitoring needs to account for the spatial variation in pollution profiles among nesting beaches. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Trematode communities in snails can indicate impact and recovery from hurricanes in a tropical coastal lagoon.

    Science.gov (United States)

    Aguirre-Macedo, María Leopoldina; Vidal-Martínez, Victor M; Lafferty, Kevin D

    2011-11-01

    In September 2002, Hurricane Isidore devastated the Yucatán Peninsula, Mexico. To understand its effects on the parasites of aquatic organisms, we analyzed long-term monthly population data of the horn snail Cerithidea pliculosa and its trematode communities in Celestún, Yucatán, Mexico before and after the hurricane (February 2001 to December 2009). Five trematode species occurred in the snail population: Mesostephanus appendiculatoides, Euhaplorchis californiensis, two species of the genus Renicola and one Heterophyidae gen. sp. Because these parasites use snails as first intermediate hosts, fishes as second intermediate hosts and birds as final hosts, their presence in snails depends on food webs. No snails were present at the sampled sites for 6 months after the hurricane. After snails recolonised the site, no trematodes were found in snails until 14 months after the hurricane. It took several years for snail and trematode populations to recover. Our results suggest that the increase in the occurrence of hurricanes predicted due to climate change can impact upon parasites with complex life cycles. However, both the snail populations and their parasite communities eventually reached numbers of individuals and species similar to those before the hurricane. Thus, the trematode parasites of snails can be useful indicators of coastal lagoon ecosystem degradation and recovery. Copyright © 2011 Australian Society for Parasitology Inc. All rights reserved.

  1. Perception Environmental Awareness and Green Areas: The Case Botanical Garden City Park in Sinop / MT, Brazil

    Directory of Open Access Journals (Sweden)

    Sinovia Cecilia Rauber

    2011-12-01

    Full Text Available This research aims to study the environmental perception of a group of residents of two neighborhoods surrounding the Botanical Garden City Park in Sinop-MT, revealing their relationship with the area as well as their involvement in proposing alternatives for the conservation of the Park. With this aim a study on the Botanical Garden Municipal Park was carried out, using the following procedures: documentary research in public agencies; site visits for description of the area and semi-structured interviews with a group of residents of two neighborhoods in the vicinity, Celeste Garden and the Botanical Garden. The presence of fauna, flora and springs that form Ribeirão Nilza within the park indicates the need for its conservation, and the residents consider the area important for the local micro weather, tourism, biodiversity conservation and also to develop researches, contributing significantly to the population's quality of life. Taking into account the above considerations, it is important to consider a new scenario, which aims to mobilize social participation, propitiating the people the feeling of belonging to what they conceive as the environment, giving rise to a participatory management by means of Environmental Education.

  2. Biodegradation of ethyl acetate in radioactive liquid organic waste by bacterial communities

    International Nuclear Information System (INIS)

    Ferreira, Rafael V.P.; Sakata, Solange K.; Borba, Tania R.; Bellini, Maria H.; Marumo, Julio T.; Dutra, Fernando

    2009-01-01

    The research and development program in reprocessing of low burn-up spent fuel elements began in Brazil in 70's, originating the lab -scale hot cell, known as CELESTE located at IPEN-CNEN/SP. The program was ended at the beginning of 90's and part of the radioactive waste generated mainly from the analytical laboratories is stored at the Waste Management Laboratory. Among various types of radioactive waste generated, the organic liquid represents a major problem for its management, because it can not be directly solidified with cement. The objective of this work is to develop a pretreatment methodology to degrade the ethyl acetate present in organic liquid waste so that it can subsequently be immobilized in cement. This work was divided into two parts: selection and adaptation of three bacterial communities for growth in medium containing ethyl acetate and degradation experiments of ethyl acetate present in radioactive organic liquid waste. The results showed that from bacterial communities the highest biodegradation level observed was 77%. (author)

  3. A new cryptogonimid (Digenea) from the Mayan cichlid, Cichlasoma urophthalmus (Osteichthyes: Cichlidae), in several localities of the Yucatán Peninsula, Mexico.

    Science.gov (United States)

    Razo-Mendivil, Ulises; Rosas-Valdez, Rogelio; Pérez-Ponce de León, Gerardo

    2008-12-01

    Oligogonotylus mayae n.sp. is described from the intestine of the Mayan cichlid Cichlasoma urophthalmus (Günther) in Ría Lagartos, Ría Celestún, and Estero Progreso, Yucatán State. This is the second species described for Oligogonotylus Watson, 1976, the other being O.manteri Watson, 1976. The new species is readily distinguished from O. manteri by the anterior extension of the vitelline follicles. In O. Manteri, Vitelline follicles are found entirely in the hindbody, extending posteriorly to mid-testicular level. Vitelline follicles in the new species extend from teh anterior margin of posterior testis to the region between the bentral sucker and the pharynx. comparison of approximately 1,850 bases of ribosomal DNA (ITS1, ITS2, 5.8S, and 28S), and 400 bases of cytochrome c oxidase subunit I (cox1) strongly supports the status of O. mayae as a new species, as compared to O. manteri collected from cichlids in other localities of Mexico, Belize, and Guatemala.

  4. La prhonesis real en la teoría política de\tChristine de Pizan

    Directory of Open Access Journals (Sweden)

    Juliana Eva Rodríguez

    2016-12-01

    Full Text Available Christine de Pizan da vida a una nueva especie de rey prudente, fraguado en la teoría aristotélica, pero adaptado a la realidad de su tiempo. Desligada de su anterior connotación cristiana, la prudencia regresa a sus raíces paganas, transformándose en una virtud civil. Asimismo, mientras se distingue de la sabiduría que conduce al conocimiento de las esferas celestes, la prudencia adquiere los rasgos de una virtud específicamente política, cuya adquisición depende exclusivamente de la capacidad humana, tanto para el más nimio de los mortales, como para el vértice de la jerarquía política. Puesto que el rey no hereda la prudencia, cabe preguntarse por la definición, el origen, y el medio de adquisición de una virtud indispensable para el buen gobierno.

  5. Pandora y Thanatia: una visión termodinámica del agotamiento de los recursos minerales

    Directory of Open Access Journals (Sweden)

    Luis Gabriel Carmona

    2015-02-01

    Full Text Available Los recursos minerales son cada vez más escasos. Este fenómeno obedece a la intensa presión ejercida por la industria minera y a los hábitos de consumo humano. Mediante la herramienta del análisis exergético es posible valorar este grado de agotamiento; sin embargo, el “lenguaje” de la termodinámica no es transferido fácilmente desde la ingeniería hacia otras esferas tales como la administración y las políticas públicas. La presente reflexión del agotamiento de recursos ha sido ilustrada de forma didáctica para que el público en general pueda entender su criticidad. Tomando como ejemplo dos cuerpos celestes: Pandora de la película Avatar de James Cameron y la hipótesis de la tierra crepuscular de Thanatia, los autores explican la exergía, el ambiente de referencia e instrumentos para la gestión de recursos. Finalmente se señala la necesidad de un mayor nivel de concientización sobre la importancia en la toma de decisiones hacia el desarrollo sostenible y la protección del patrimonio geológico.

  6. Historical sketch of the Freinet’ movement in Spain. 1926-1939

    Directory of Open Access Journals (Sweden)

    José María Hernández díaz

    2007-09-01

    Full Text Available The postulates on education from Celestín Freinet, and his determination to provide to the Cooperative of Lay Education (CLE of an international character, came out soon the French borders. Spain was not foreign to such influence and, very soon, the Freinet’s educational offer had a good reception, even though, in the first moment, it had scanty diffusion and minor application. The winds of pedagogic renovation, propitiated by the Spanish Second Republic, gave impulse and encouraged the application of the new educational technologies from France. Thus, the incipient Freinet’s Spanish movement was taking shape and, in a little time, this had a «battalion» of «sniper» teachers, who wanted to apply those ideas, a solid organization and a promising future truncated by the beginning of the civil war. This research is about the Spanish receipt from the Modern School, the advertising and diffusion of those ideas, the itinerary followed by the Spanish’s Freynet move- ment during it expansion and Franco’s government. Likewise, this paper presents a profile of the Freynet’s teachers movement in Spain, and a census of school notebooks realized through the school press, with expression of the locality of edition and of the teachers who stimulated the publication. Key words: Freinet, Spain, Second Republic, Purge, School notebooks, Pedagogic renovation. 

  7. Intravenous ibuprofen: the first injectable product for the treatment of pain and fever

    Directory of Open Access Journals (Sweden)

    P Brandon Bookstaver

    2010-05-01

    Full Text Available P Brandon Bookstaver, April D Miller, Celeste N Rudisill, LeAnn B NorrisDepartment of Clinical Pharmacy and Outcomes Sciences, South Carolina College of Pharmacy, University of South Carolina Campus, Columbia, South Carolina, USAAbstract: This paper reviews the current data on the use of the first approved intravenous ibuprofen product for the management of post-operative pain and fever in the United States. The management of acute and post-operative pain and fever with nonsteroidal anti-inflammatory agents (NSAIDs is well documented. A search in Medline and International Pharmaceutical Abstracts of articles until the end of November 2009 and references of all citations were conducted. Available manufacturer data on file were also analyzed for this report. Several randomized controlled studies have demonstrated the opioid-sparing and analgesic effects of 400 and 800 mg doses of intravenous ibuprofen in a series of post-operative patient populations. Two recent studies have also noted the improvement in fever curves in critically ill and burn patients. These data, along with pharmacokinetic and pharmacologic properties, are explored in this review, which addresses the clinical utility of a parenteral NSAID in a hospitalized patient for post-operative pain management and fever reduction. Further data on intravenous ibuprofen are needed to define long-term utilization, management of acute pain, and use in special populations.Keywords: ibuprofen, intravenous, injectable, nonsteroidal anti-inflammatory drug

  8. Effect of dietary supplement (cevas on the chemical composition of wild fish Brycon falcatus Müller & Troschel, 1844 in the Teles Pires river basin

    Directory of Open Access Journals (Sweden)

    Liliane Stedile Matos

    2017-05-01

    Full Text Available In the Teles Pires River watershed, one of the most common techniques currently used by fishermen to catch fish is to provide a food supplement commonly known as “cevas”. The purpose of this study was to compare the chemical composition of fillets from Brycon falcatus that were caught in both the presence and absence of cevas. The fish were sampled monthly and captured in the following conditions: the Tapaiúna River without cevas, the Teles Pires River with one ceva/100 m, the Celeste River with one ceva/500 m, the Verde River with one ceva/1000 m and the Cristalino River (control area. Subsequent to capture, the fish were euthanized and preserved on ice to determine their water, ash, crude protein and fat contents. Fillets of fish from the control area exhibited a lower level of crude protein (17.81% compared with that of fish from the other rivers, which did not differ amongst one other. The fillets of fish from the river with the greatest density of cevas (1/100 m exhibited a higher fat content (3.63% than that of fish from the control area (1.51%. Thus, the cevas changed the chemical composition of B. falcatus fillets.

  9. Methane and sulfate dynamics in sediments from mangrove-dominated tropical coastal lagoons, Yucatan, Mexico

    Science.gov (United States)

    Chuang, P. C.; Young, Megan B.; Dale, Andrew W.; Miller, Laurence G.; Herrera-Silveira, Jorge A.; Paytan, Adina

    2016-01-01

    Porewater profiles in sediment cores from mangrove-dominated coastal lagoons (Celestún and Chelem) on the Yucatán Peninsula, Mexico, reveal the widespread coexistence of dissolved methane and sulfate. This observation is interesting since dissolved methane in porewaters is typically oxidized anaerobically by sulfate. To explain the observations we used a numerical transport-reaction model that was constrained by the field observations. The model suggests that methane in the upper sediments is produced in the sulfate reduction zone at rates ranging between 0.012 and 31 mmol m−2 d−1, concurrent with sulfate reduction rates between 1.1 and 24 mmol SO42− m−2 d−1. These processes are supported by high organic matter content in the sediment and the use of non-competitive substrates by methanogenic microorganisms. Indeed sediment slurry incubation experiments show that non-competitive substrates such as trimethylamine (TMA) and methanol can be utilized for microbial methanogenesis at the study sites. The model also indicates that a significant fraction of methane is transported to the sulfate reduction zone from deeper zones within the sedimentary column by rising bubbles and gas dissolution. The shallow depths of methane production and the fast rising methane gas bubbles reduce the likelihood for oxidation, thereby allowing a large fraction of the methane formed in the sediments to escape to the overlying water column.

  10. Astronomy in Brazilian music and poetry

    Science.gov (United States)

    de Freitas Mourão, Ronaldo Rogério

    2011-06-01

    The rôle of astronomy in the Brazilian cultural diversity -though little known world- has been enormous. Thus, the different forms of popular music and erudite, find musical compositions and lyrics inspired by the stars, the eclipses in rare phenomena such as the transit of Venus in front of the sun in 1882, the appearance of Halley's Comet in 1910, in the Big Bang theory. Even in the carnival parades of the blocks at the beginning of the century astronomy was present. More recently, the parade of 1997, the samba school Unidos do Viradouro, under the direction of Joãozinho Trinta, offered a new picture of the first moments of the creation of the universe to join in the white and dark in the components of their school, the idea of matter and anti-matter that reigned in the early moments of the creation of the universe in an explosion of joy. Examples in classical music include Dawn of Carlos Gomes and Carta Celeste by Almeida Prado. Unlike The Planets by Gustav Holst -who between 1914 and 1916 composed a symphonical tribute to the solar system based on astrology- Almeida Prado composed a symphony that is not limited to the world of planets, penetrating the deep cosmos of galaxies. Using various resources of the technique for the piano on the clusters and static movements, violent conflicts between the records of super acute and serious instrument, harpejos cross, etc . . .

  11. Modelos cosmológicos en la Ciencia Escolar. Aportes desde la historia de la ciencia para su enseñanza – aprendizaje

    Directory of Open Access Journals (Sweden)

    Johanna Patricia Camacho González

    2016-12-01

    Full Text Available Esta investigación tuvo por objetivo analizar los modelos explicativos del estudiantado de séptimo básico (11 – 12 años acerca del sistema Solar, antes y después de una intervención didáctica que incluía la historia de la ciencia en la enseñanza de los modelos cosmológicos, considerando el Modelo Cognitivo de Ciencia (Giere, 1992. El diseño metodológico se desarrolló a través de dos etapas: a. Diseño y validación de una unidad didáctica, desde el Ciclo Constructivista de Aprendizaje (Sanmartí, 2000 y, b. Identificación y comparación de los modelos explicativos estudiantiles antes y después de la intervención didáctica. Los principales resultados evidencian que el aporte de la historia de la ciencia es significativo para la construcción de modelos explicativos dinámicos, complejos y flexibles acerca de los modelos cosmológicos, los cuales se caracterizan por incluir nuevos elementos, establecer más relaciones entre los cuerpos celestes y poseer un lenguaje más especializado.

  12. Sobre el soneto Los conquistadores de los trofeos

    Directory of Open Access Journals (Sweden)

    Carlos López Narváez

    1967-09-01

    Full Text Available Aun los medianamente eruditos en poesía francesa sobradamente saben que el autor del más celebrado poemario parnasiano -cuyo subtítulo puede ser Historia celeste de la tierra- el cubano-francés José María de Heredia, ascendía (el usual descendia no cu¡tdra en esta anécdota de gloria del conquistador y fundador don Pedro de Heredia, alias el desna- rigado, y de allí el que de las propias arterias apriemiárale un férvido interés por el mundo occidental en todos sus órdenes. Empezó por acometer la versión francesa de la monumental crónica historial de Bernal Díaz del Castillo, labor cuya culminación científica y artística culmina en las notas y acotaciones complementarias del original vertido y que denuncian, por igual sabiduría y pasión americanistas: tanto, que en su biblioteca de trabajo se alineaban cerca de dos centenares de obras sobre el Nuevo Mundo. La epopeya acabó, naturalmente por encender el instinto épico del abolengo hasta hacer del poeta el Benvenuto Cellini del soneto parnasiano. El primer indicio aparece en el titulado Los funerales, insuperablemente traducido por Otto de Greiff.

  13. EXERCÍCIOS ENVOLVENDO A MAGNITUDE LIMITE NO ENSINO DE ASTRONOMIA

    Directory of Open Access Journals (Sweden)

    Lev Vertchenko

    Full Text Available Neste trabalho são apresentados alguns exercícios e atividades, elaborados para disciplinas de Astronomia Básica e inspirados na propos ta de exploração multicontextual de Ausubel, relacionando o conceito de magnitude limite ao poder de captação de luz de um instrumento ótico. Os resultados desses exercícios são comparados a contagens de estrelas, obtidas seja pela observação, a olho nu ou com instrumentos óticos, seja pelo uso de software do tipo carta celeste. O processo inclui a familiariza ção do estudante com o céu, com binóculos e telescópios e com vários softwares. São discutidas a relação dessas contagens com a distribuição espa cial das estrelas, e sua aplicabilidade a situações de ensino/aprendizagem.

  14. Mission to stars: un proyecto de investigación alrededor de la astronomía, las misiones espaciales y la investigación científica

    Directory of Open Access Journals (Sweden)

    Jordi Domènech-Casal

    2017-01-01

    Full Text Available En la enseñanza de las ciencias, los alumnos deben adquirir habilidades científicas, que se ubican en el currículum de las materias científicas de Secundaria como « Proyecto de investigación » . La Enseñanza de las Ciencias Basada en la Indagación y el Aprendizaje Basado en Proyectos son enfoques metodológicos candidatos para su abordaje. Se ha construido y aplicado una actividad de « Proyecto de Investigación » en el contexto curricular de la Astronomía de 1º de ESO, en la que los alumnos planifican una misión espacial diseñando experimentos, identificando y ubicando cuerpos celestes y sus distancias y realizando un presupuesto de la misión junto con un modelo 3D de un telescopio orbital y un programa informático para automatizarlo. Se describe la actividad y los resultados de su aplicación se recogen con la ayuda de una encuesta, un examen y análisis de producciones del alumnado. Se analizan las concepciones del Universo del alumnado y se ofrecen indicaciones para el desarrollo de nuevas actividades.

  15. The First Post-Kepler Brightness Dips of KIC 8462852

    Science.gov (United States)

    Boyajian, Tabetha. S.; Alonso, Roi; Ammerman, Alex; Armstrong, David; Asensio Ramos, A.; Barkaoui, K.; Beatty, Thomas G.; Benkhaldoun, Z.; Benni, Paul; Bentley, Rory O.; Berdyugin, Andrei; Berdyugina, Svetlana; Bergeron, Serge; Bieryla, Allyson; Blain, Michaela G.; Capetillo Blanco, Alicia; Bodman, Eva H. L.; Boucher, Anne; Bradley, Mark; Brincat, Stephen M.; Brink, Thomas G.; Briol, John; Brown, David J. A.; Budaj, J.; Burdanov, A.; Cale, B.; Aznar Carbo, Miguel; Castillo García, R.; Clark, Wendy J.; Clayton, Geoffrey C.; Clem, James L.; Coker, Phillip H.; Cook, Evan M.; Copperwheat, Chris M.; Curtis, J. L.; Cutri, R. M.; Cseh, B.; Cynamon, C. H.; Daniels, Alex J.; Davenport, James R. A.; Deeg, Hans J.; De Lorenzo, Roberto; de Jaeger, Thomas; Desrosiers, Jean-Bruno; Dolan, John; Dowhos, D. J.; Dubois, Franky; Durkee, R.; Dvorak, Shawn; Easley, Lynn; Edwards, N.; Ellis, Tyler G.; Erdelyi, Emery; Ertel, Steve; Farfán, Rafael. G.; Farihi, J.; Filippenko, Alexei V.; Foxell, Emma; Gandolfi, Davide; Garcia, Faustino; Giddens, F.; Gillon, M.; González-Carballo, Juan-Luis; González-Fernández, C.; González Hernández, J. I.; Graham, Keith A.; Greene, Kenton A.; Gregorio, J.; Hallakoun, Na’ama; Hanyecz, Ottó; Harp, G. R.; Henry, Gregory W.; Herrero, E.; Hildbold, Caleb F.; Hinzel, D.; Holgado, G.; Ignácz, Bernadett; Ilyin, Ilya; Ivanov, Valentin D.; Jehin, E.; Jermak, Helen E.; Johnston, Steve; Kafka, S.; Kalup, Csilla; Kardasis, Emmanuel; Kaspi, Shai; Kennedy, Grant M.; Kiefer, F.; Kielty, C. L.; Kessler, Dennis; Kiiskinen, H.; Killestein, T. L.; King, Ronald A.; Kollar, V.; Korhonen, H.; Kotnik, C.; Könyves-Tóth, Réka; Kriskovics, Levente; Krumm, Nathan; Krushinsky, Vadim; Kundra, E.; Lachapelle, Francois-Rene; LaCourse, D.; Lake, P.; Lam, Kristine; Lamb, Gavin P.; Lane, Dave; Lau, Marie Wingyee; Lewin, Pablo; Lintott, Chris; Lisse, Carey; Logie, Ludwig; Longeard, Nicolas; Lopez Villanueva, M.; Whit Ludington, E.; Mainzer, A.; Malo, Lison; Maloney, Chris; Mann, A.; Mantero, A.; Marengo, Massimo; Marchant, Jon; Martínez González, M. J.; Masiero, Joseph R.; Mauerhan, Jon C.; McCormac, James; McNeely, Aaron; Meng, Huan Y. A.; Miller, Mike; Molnar, Lawrence A.; Morales, J. C.; Morris, Brett M.; Muterspaugh, Matthew W.; Nespral, David; Nugent, C. R.; Nugent, Katherine M.; Odasso, A.; O’Keeffe, Derek; Oksanen, A.; O’Meara, John M.; Ordasi, András; Osborn, Hugh; Ott, John J.; Parks, J. R.; Rodriguez Perez, Diego; Petriew, Vance; Pickard, R.; Pál, András; Plavchan, P.; Pollacco, Don; Pozo Nuñez, F.; Pozuelos, F. J.; Rau, Steve; Redfield, Seth; Relles, Howard; Ribas, Ignasi; Richards, Jon; Saario, Joonas L. O.; Safron, Emily J.; Sallai, J. Martin; Sárneczky, Krisztián; Schaefer, Bradley E.; Schumer, Clea F.; Schwartzendruber, Madison; Siegel, Michael H.; Siemion, Andrew P. V.; Simmons, Brooke D.; Simon, Joshua D.; Simón-Díaz, S.; Sitko, Michael L.; Socas-Navarro, Hector; Sódor, Á.; Starkey, Donn; Steele, Iain A.; Stone, Geoff; Strassmeier, Klaus G.; Street, R. A.; Sullivan, Tricia; Suomela, J.; Swift, J. J.; Szabó, Gyula M.; Szabó, Róbert; Szakáts, Róbert; Szalai, Tamás; Tanner, Angelle M.; Toledo-Padrón, B.; Tordai, Tamás; Triaud, Amaury H. M. J.; Turner, Jake D.; Ulowetz, Joseph H.; Urbanik, Marian; Vanaverbeke, Siegfried; Vanderburg, Andrew; Vida, Krisztián; Vietje, Brad P.; Vinkó, József; von Braun, K.; Waagen, Elizabeth O.; Walsh, Dan; Watson, Christopher A.; Weir, R. C.; Wenzel, Klaus; Westendorp Plaza, C.; Williamson, Michael W.; Wright, Jason T.; Wyatt, M. C.; Zheng, WeiKang; Zsidi, Gabriella

    2018-01-01

    We present a photometric detection of the first brightness dips of the unique variable star KIC 8462852 since the end of the Kepler space mission in 2013 May. Our regular photometric surveillance started in 2015 October, and a sequence of dipping began in 2017 May continuing on through the end of 2017, when the star was no longer visible from Earth. We distinguish four main 1%–2.5% dips, named “Elsie,” “Celeste,” “Skara Brae,” and “Angkor,” which persist on timescales from several days to weeks. Our main results so far are as follows: (i) there are no apparent changes of the stellar spectrum or polarization during the dips and (ii) the multiband photometry of the dips shows differential reddening favoring non-gray extinction. Therefore, our data are inconsistent with dip models that invoke optically thick material, but rather they are in-line with predictions for an occulter consisting primarily of ordinary dust, where much of the material must be optically thin with a size scale ≪1 μm, and may also be consistent with models invoking variations intrinsic to the stellar photosphere. Notably, our data do not place constraints on the color of the longer-term “secular” dimming, which may be caused by independent processes, or probe different regimes of a single process.

  16. Clinical potential of mechlorethamine gel for the topical treatment of mycosis fungoides-type cutaneous T-cell lymphoma: a review on current efficacy and safety data

    Directory of Open Access Journals (Sweden)

    Liner K

    2018-01-01

    Full Text Available Kendall Liner,1 Celeste Brown,2 Laura Y McGirt3 1Division of Dermatology, Medical College of Georgia at Augusta Health, Augusta, GA, USA; 2School of Medicine, University of North Carolina at Chapel Hill, Carolinas Medical Center, Charlotte, NC, USA; 3Department of Hematology/Oncology, Levine Cancer Institute, Carolinas Medical Center, Charlotte, NC, USA Abstract: Nitrogen mustard is a chemotherapeutic agent that has a well-documented safety and efficacy profile in the treatment of cutaneous T-cell lymphoma. Development of nitrogen mustard formulations and treatment regimens has been studied extensively over the last 40 years. In the last 5 years, a new gel formulation has been developed that is associated with a decrease in delayed hypersensitivity reactions. The authors in this review found that while the gel formulation may result in a decrease of allergic contact dermatitis, this advantage has been replaced by a higher number of irritant contact reactions and a decrease in complete response rate. The gel formulation has a complete response rate of 13.8%, which is a decrease in efficacy when compared to aqueous-based preparations of similar concentrations. Keywords: mycosis fungoides, nitrogen mustard, mechlorethamine gel, cutaneous T-cell lymphoma, CTCL, Valchlor®

  17. Experimental high energy physics in the Czech Republic

    International Nuclear Information System (INIS)

    Suk, M.

    1998-01-01

    Within Czech collaboration with CERN, physicists, technicians, and students participate in the DELPHI project; this is a large detection unit measuring a vast volume of data of particles which are produced in collisions of electrons with positrons on the LEP accelerator at a total energy from 100 to 190 GeV. The building-up of the ATLAS detection system on the LHC accelerator which is under construction (total energy 14 TeV) is another major project addressed in cooperation with CERN, as is the DIRAC project within which the Czech party is engaged in the construction of the detector and makes preparations for measurements of space-time asymmetries in the production of particles. In the DESY laboratory, Czech scientists participate in the implementation of the H1 detector programme on the HERA electron and proton accelerator (total energy about 300 GeV). In the American FERMILAB, Czech scientists and technicians are involved in instrumentation upgrading and in the processing of physical results from data obtained during experiments with the D0 detector in the proton beam of the TEVATRON accelerator (total energy 1.8 TeV). In the field of cosmic ray physics, cooperation within the CAT and CELESTE projects (Cherenkov gamma telescope) is in progress under the leadership of French laboratories

  18. El Uranolito de Chaguaní: Consideraciones en torno a los meteoritos

    Directory of Open Access Journals (Sweden)

    Tovar Ariza Rafael

    1942-06-01

    Full Text Available Desde épocas muy remotas se afirmaba por pueblos de diverso origen y de regiones apartadas entre sí que de cuando en cuando caían en la Tierra piedras más o menos grandes, provenientes del cielo. Esta aserción, hoy plenamente aceptada por todos y casi cotidianamente corroborada, fue sistemáticamente rechazada por muchos círculos doctos, que rehusaron aceptar la realización de tal fenómeno por juzgar que contradecía los principios de la mecánica celeste. A lo sumo se admitía la posibilidad de que algunas piedras arrojadas con enorme fuerza por volcanes terrestres fueran a dar a lugares muy alejados de la erupción ígnea, donde ignorándose la conmoción volcánica respectiva, se atribuyera a tales piedras origen extra-terrestre.

  19. El lenguaje ruidoso: la dramaturgia femenina contemporánea en el Perú

    Directory of Open Access Journals (Sweden)

    Elena Guichot Muñoz

    2014-06-01

    Full Text Available La dramaturgia femenina, recogida escasamente en la historia oficial de la literatura peruana, posee desde finales del siglo XIX voces de dramaturgas que se suceden con éxito y permanencia en cada una de las generaciones. En este artículo estudiaremos dos piezas de dos autoras contemporáneas: Mariana de Althaus y Celeste Viale Yerobi, escritoras que rompen el silencio con una escritura comprometida con su identidad femenina y con su momento histórico, convuslionado por los sucesos acaecidos en el conflicto armado que comienza e la década de los ochenta. LLevaremos a cabo un análisis en cotejo de una pieza teatral de cada una de estas escritoras desde un punto de vista no meramente estético sino antropológico, social y cultural, con el fin de alcanzar su realidad fragmentada, el duelo de las escritoras en las dictaduras, las censuras implícitasy su impactante desnudo en la escena.

  20. A New ′Conservation Space′? Protected Areas, Environmental Economic Activities and Discourses in Two Yucatán Biosphere Reserves in Mexico

    Directory of Open Access Journals (Sweden)

    Sabrina Doyon

    2014-01-01

    Full Text Available This article examines some of the local socioeconomic repercussions of two biosphere reserves on the Yucatán Peninsula-Ría Celestún and Ría Lagartos. We analyse aspects of the relationship that the residents of the six villages located within the two reserves have with their environment, by examining both the ′environmental economic activities′ residents are involved in and their discourses on, and interpretations of, the notion of environment and the conservation precepts put forward by the biosphere reserves. Our research explores how the objectives of the United Nations Educational, Scientific and Cultural Organization′s Man and Biosphere Programme, disseminated by biosphere reserves, are put into practice on the ground. In particular, we look at how environmental economic activities are experienced and practised without necessarily being accompanied by the integration, acceptance, and internalisation of conservation principles-and how these activities contribute, or fail to contribute, to the crystallisation of a new ′conservation space′.

  1. Study of the high temperature oxidation of nickel; Contribution a l'etude de l'oxydation du nickel aux temperatures elevees

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-11-01

    The parabolic oxidation of nickel by oxygen and by air at atmospheric pressure has been studied in the temperature range 600 to 1400 C, in particular by thermogravimetric and micrographic techniques. The mechanism of the reaction has been determined; it has been shown in particular that the break in the Arrhenius plot of the kinetics, occurring at about 950 C, is the result of a stimulation of the diffusion across the nickel prot-oxide film above this temperature; this is the result of the presence of excess nickel vacancies in the film. A systematic study has also been made of the influence of the oxygen pressure P{sub O{sub 2}} (10{sup -2} torr {<=} P{sub O{sub 2}} {<=} 760 torr) on the parabolic oxidation of nickel between 800 and 1400 C. In the range 1000 to 1400 C, the activation energy of the process decreases monotonously from 57 to 34 kcal/mole as P{sub O{sub 2}} decreases from 760 to 1 torr. Furthermore, it has been shown that the parabolic oxidation constant is proportional to P{sub O{sub 2}}{sup 1/n} the value of n is not invariant however in the temperature range examined, but decreases from 6 to about 3 when the temperature increases from 900 to 1400 C. Finally, a study has been made of the oxidation of nickel in carbon dioxide at atmospheric pressure between 750 and 1400 C. The main reaction is Ni + CO{sub 2} {yields} NiO + CO, and corresponds, with a good approximation, to the reaction of the metal with the oxygen produced by the thermal dissociation of the CO{sub 2}. (author) [French] L'oxydation parabolique du nickel avec l'oxygene et l'air a la pression atmospherique a ete etudiee dans l'intervalle de temperatures 600-1400 C, surtout par voies thermogravimetrique et micrographique. Le mecanisme de la reaction a ete precise; en particulier, il a ete montre que la brisure de la courbe d'Arrhenius traduisant sa cinetique, qui se produit a 950 C environ, resulte d'une stimulation de la diffusion dans la pellicule de protoxyde de nickel au dessous de

  2. Installation for the study of heat transfer with high flux density; Installation d'etude de transmission de chaleur a densite de flux elevee

    Energy Technology Data Exchange (ETDEWEB)

    Robin, M; Schwab, B [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1957-07-01

    As a result of their very low vapor pressure, metals with a low fusion point (sodium, sodium-potassium alloys, etc.) can be used at high temperature, as heating fluids, in installations whose internal pressure is close to atmospheric pressure. Owing to the very high convection coefficients which can be reached with these fluids and to the large temperature differences utilizable, it is possible to produce through the exchange surfaces considerable heat flux densities, of the order of those which exist through the canning of fuel elements in nuclear reactors. The installation described allowed a flux density of more than 200 W/cm{sup 2} to be obtained, the heating fluid being a Na-K alloy (containing 56 per cent by weight of potassium) brought to a temperature around 550 deg. C. (author) [French] Par suite de leur tres faible pression de vapeur, les metaux a bas point de fusion (sodium, alliages sodium-potassium, etc.) peuvent etre utilises a haute temperature, comme fluides de chauffage, dans des installations dont la pression interne est voisine de la pression atmospherique. Grace aux coefficients de convection tres eleves que ces fluides permettent d'atteindre et aux importantes differences de temperature utilisables, il est possible de produire, a travers les surfaces d'echange, des densites de flux de chaleur considerables, de l'ordre de celles qui existent a travers les gaines des elements combustibles des reacteurs nucleaires. L'installation decrite a permis l'obtention d'une densite de flux de plus, de 200 W/cm{sup 2}, le fluide chauffant etant de l'alliage Na-K (a 56 pour cent en poids de potassium) porte a une temperature voisine de 550 deg. C. (auteur)

  3. A contribution to the study of the mixed uranium-plutonium mono-carbides containing small quantities of zirconium; Contribution a l'etude du monocarbure d'uranium et de plutonium avec de faibles additions de zirconium

    Energy Technology Data Exchange (ETDEWEB)

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

    1970-03-01

    We have studied a mixed monocarbide, type (U,Pu)C, containing small additions of zirconium for the application as a fast neutron reactor fuel. A preliminary study was conducted on the (U,Zr)C monocarbide (Report CEA-R-3765(1). It was found that small additions of zirconium to the uranium-plutonium monocarbide improve a number of properties such as atmospheric corrosion, the hardness, and particularly the compatibility with 316 stainless steel. However, properties such as the coefficient of expansion and the melting point are only slightly changed. The relative percentage of Pu/U+Pu in the monocarbide was fixed at 20 per cent. Two processes of fabrication were employed: casting in an arc furnace, sintering, carried out after having the hydrides of the metals carburized. The metallurgical results indicate, that the above mentioned fuel might be of interest for fast neutron reactor application. (author) [French] On a etudie un combustible de type carbure (U,Pu)C pour les reacteurs a neutrons rapides. Les recherches preliminaires ont porte sur le carbure (UZr)C (rapport CEA-R-3765(1)). L'addition de faibles quantites de zirconium (3 at. pour cent) au monocarbure (U,Pu)C, ameliore certaines proprietes, commee la tenue a la corrosion atmospherique, la durete et surtout la compatibilite avec l'acier inoxydable X-18 M, Par contre le coefficient de dilatation et la densite sont peu changes. Le rapport Pu/Pu+U etait fixe a 20 pour cent. Deux procedes de fabrication ont ete etudies: l'un par fusion a l'arc, l'autre par frittage a partir de metaux hydrures. Au vu des resultats metallurgiques obtenus le carbure (U,Pu,Zr)C semble presenter un interet certain. (auteur)

  4. The health physics of installations for decladding irradiated fuels or for handling radio-elements at Marcoule; La radioprotection des installations de degainage des combustibles irradies et des radio-elements a Marcoule

    Energy Technology Data Exchange (ETDEWEB)

    Chassany, J; Guillermin, P; Mallet, P [Commissariat a l' Energie Atomique, Centre de Production de Plutonium de Marcoule, 30 - Chusclan (France)

    1966-07-01

    Radiation protection practices for handling reactor fuel elements are described. Elements of considerable specific radioactivity are handled under water. A study was made of water filtration and of ventilation in the building. The installations are divided up into zones depending on the radioactive risks, and the radiation level atmospheric contamination are the object of a systematic control at various points. A description is given of all aspects of health physics which have been encountered during six years: storage, transfer of radioactive material; decladding, rolling, waste disposal, specialized operations, installations in operation and at rest, and transport. In spite of the gradual increase in the activity of these installations, the total doses received by the personnel have hardly altered and the number of cases of physical contamination has diminished. (authors) [French] Dans ces installations, se manipulent sous l'eau des elements a radioactivite specifique considerable. La filtration de l'eau, la ventilation ont ete particulierement etudiees. L'ensemble a ete divise en lieux classes en fonction des risques radioactifs et des appareils controlent en permanence l'irradiation et la contamination atmospherique en certains points. Tous les aspects de la radioprotection resultant de six annees d'experience relatifs: au stockage, au deconteneurage, au degainage, au laminage, a l'evacuation des residus, aux travaux particuliers, installations en marche et a l'arret, et aux transports sont successivement decrits. Malgre l'accroissement progressif de l'activite de cet ensemble, les doses integrees par le personnel n'ont pratiquement pas augmente et le nombre des cas de contamination corporelle a diminue. (auteurs)

  5. Study of radio-active ions in the atmosphere; Etude des ions radioactifs de l'atmosphere

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-01-01

    A comparative study is made of active, deposits of radon and thoron in suspension in the atmosphere by means of {alpha} radiation counting, using ZELENY tubes, scattering equipment, filter papers or membranes. It has been possible to show the existence of small and large ions which are negative and positive, as well as of neutral radio-active nuclei; their properties are studied. A theoretical interpretation of the results is presented. The average content of radon (using the Ra A concentration) and of Th B in the air has been determined. The radioactive equilibrium between radon and its daughter products in atmospheric air are examined. The techniques developed for active radon and thoron deposits are applied to the study of artificial radio-activity, the analyses being carried out by means of {gamma} spectrometry. (author) [French] On effectue une etude comparative entre les depots actifs du radon et du thoron en suspension dont l'atmosphere a l'aide de comptages de rayonnement {alpha}, en utilisant des tubes de ZELENY, une batterie de diffusion, des papiers filtres ou des membranes. On met ainsi en evidence la presence de petits et gros ions negatifs et positifs, ainsi que celle de noyaux neutres radioactifs, et on etudie leurs proprietes. Une Interpretation theorique des resultats obtenus est developpee. On determine la teneur moyenne de l'air en radon (a partir de la concentration en Ra A) et en Th B. L'equilibre radioactif entre le radon et ses descendants, dans l'air atmospherique, est examine. Les Techniques mises au point pour les depots actifs du radon et du thoron sont appliquees a l'etude de la radioactivite artificielle, les depouillements s'effectuant par spectrometrie {gamma}. (auteur)

  6. Argon activation analysis, application to dating by the potassium-argon method; Analyse par activation de l'argon. Application a la datation par la methode potassium-argon

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-07-01

    Activation analysis using radiogenic argon-40 has been applied to rock-dating by the K-Ar method. The argon is extracted from the sample, purified, activated to saturation in a flux of 2 X 10{sup 13} neutrons/cm{sup 2} sec{sup -1} and measured by gamma spectroscopy. The sensitivity obtained is such that it is possible to measure amounts of argon corresponding to age of a few thousand years only. However since it has not been possible to measure the amount of pollution of radiogenic argon by atmospheric argon with any accuracy, the measurable age limit is in fact of the order of MY. The method has been applied to basalts from the Mont-Dore region. The results obtained are in fairly good agreement with geological, stratigraphic and paleomagnetic data. (author) [French] L'analyse par activation de l'argon 40 radiogenique a ete appliquee a la datation des roches par la methode K-Ar. L'argon est extrait de l'echantillon, purifie, active a saturation dans un flux de 2.10{sup 13} neutrons.cm{sup -2}.s{sup -1} et mesure en spectrometrie gamma. La sensibilite obtenue est telle qu'il est possible de mesurer des quantites d'argon correspondant a des ages de quelques milliers d'annees seulement. Cependant la correction de pollution de l'argon radiogenique par l'argon atmospherique n'ayant pu etre etablie avec precision, la limite d'age mesurable pratique est de l'ordre de 1 Ma. La methode a ete appliquee aux basaltes de la region du Mont-Dore. Les ages obtenus sont en assez bon accord avec les donnees geologiques, stratigraphiques et paleomagnetiques. (auteur)

  7. An automatic device for refilling liquid nitrogen traps at constant time intervals; Dispositif automatique assurant le remplissage de pieces en azote liquide a intervales de temps constant

    Energy Technology Data Exchange (ETDEWEB)

    Bourguillot, R; Lohez, P [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    We have been led to study the design of an automatic device for the filling of liquid nitrogen traps at constant time intervals in connection with the maintenance of a type MS 5 mass spectrometer; in the tube of this apparatus it is necessary to maintain a vacuum of about 10{sup -7} mm of mercury. The replenishing is done every four hours. The presence in the vacuum section of an electron multiplier has led us to provide a safety-device making it impossible for mercury vapour to come into contact with either the copper tube or the multiplier in the event of an incident leading to the warming up of the traps. In case of a breakdown, the vacuum section is therefore brought up to atmospheric pressure by the introduction of nitrogen. (author) [French] Nous avons ete conduits pour la maintenance d'un spectrometre de masse type MS 5, dans le tube duquel il faut entretenir un vide de quelques 10{sup -7} mm de mercure, a etudier un systeme de remplissage automatique a intervalle de temps fixe des pieges en azote liquide. Ce remplissage se fait toutes les quatre heures. La presence dans l'enceinte sous vide, d'un multiplicateur d'electrons, nous a amenes a prevoir un systeme de securite evitant de mettre le tube en cuivre et le multiplicateur en contact avec la vapeur de mercure en cas d'incident amenant le rechauffage des pieges. En cas de panne, l'enceinte sous vide est donc ramenee a la pression atmospherique par une introduction d'azote. (auteur)

  8. Laboratory estimate of the regional shortwave refractive index and single scattering albedo of mineral dust from major sources worldwide

    Science.gov (United States)

    Di Biagio, C.; Formenti, P.; Caponi, L.; Cazaunau, M.; Pangui, E.; Journet, E.; Nowak, S.; Caquineau, S.; Andreae, M. O.; Kandler, K.; Saeed, T.; Piketh, S.; Seibert, D.; Williams, E.; Balkanski, Y.; Doussin, J. F.

    2017-12-01

    Mineral dust is one of the most abundant aerosol species in the atmosphere and strongly contributes to the global and regional direct radiative effect. Still large uncertainties persist on the magnitude and overall sign of the dust direct effect, where indeed one of the main unknowns is how much mineral dust absorbs light in the shortwave (SW) spectral range. Aerosol absorption is represented both by the imaginary part (k) of the complex refractive index or the single scattering albedo (SSA, i.e. the ratio of the scattering to extinction coefficient). In this study we present a new dataset of SW complex refractive indices and SSA for mineral dust aerosols obtained from in situ measurements in the 4.2 m3 CESAM simulation chamber at LISA (Laboratoire Interuniversitaire des Systemes Atmospheriques) in Créteil, France. Investigated dust aerosol samples were issued from major desert sources worldwide, including the African Sahara and Sahel, Eastern Asia, the Middle East, Southern Africa, Australia, and the Americas, with differing iron oxides content. Results from the present study provide a regional mapping of the SW absorption by dust and show that the imaginary part of the refractive index largely varies (by up to a factor 6, 0.003-0.02 at 370 nm and 0.001-0.003 at 950 nm) for the different source areas due to the change in the particle iron oxide content. The SSA for dust varies between 0.75-0.90 at 370 nm and 0.95-0.99 at 950 nm, with the largest absorption observed for Sahelian and Australian dust aerosols. Our range of variability for k and SSA is well bracketed by already published literature estimates, but suggests that regional‒dependent values should be used in models. The possible relationship between k and the dust iron oxides content is investigated with the aim of providing a parameterization of the regional‒dependent dust absorption to include in climate models.

  9. 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

  10. Scintillation detector for dosing unknown {beta} emitters deposited on large-surface filters (1963); Detecteur a scintillation pour la dosimetrie d'emetteurs beta inconnus deposes sur filtre de grande surface (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Soudain, G; Cercy, J; Geoffre, B [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-07-01

    The apparatus described has been specially studied for direct counting, using a plastic scintillator, of unknown emitters occurring in atmospheric samples collected on large-surface filters (10 cm diameter). In view of the fairly large contribution of low-energy fission products to the overall {beta}-activity of radio-active fallout, the adjustments have been chosen so as to obtain the best yield in an energy range as wide as possible. This has led to the acceptance of a certain background noise which is later reduced by the anti-coincidence method. The quality of the apparatus depends largely on the uniformity of the photocathode in the photomultiplier used. The counter which was built had a counting efficiency for a 10 cm diameter source of 30 per cent for S-35, 88 per cent for P-32, 45 per cent for unknown emitters and a background noise of 56 cpm. (authors) [French] L'appareil decrit a ete specialement etudie pour le comptage direct, a l'aide d'un scintillateur plastique d'emetteurs inconnus recueillis dans les prelevements atmospheriques sur des filtres de grande surface (10 cm de diametre). Etant donne la participation assez importante des produits de fission de faible energie a l'activite globale {beta} des retombees radioactives, les reglages ont ete choisis de maniere a obtenir le meilleur rendement dans une gamme d'energie aussi etendue que possible. Cela a conduit a admettre un certain bruit de fond que l'on reduit ensuite par la methode d'anticoincidence. La qualite de l'appareil depend en grande partie de l'uniformite de la photocathode du photomultiplicateur utilise. Le compteur que l'on a construit possede une efficacite de comptage pour une source de 10 cm de diametre de 30 pour cent pour {sup 35}S, 88 pour cent pour {sup 32}P, 45 pour des emetteurs {beta} inconnus et un bruit de fond de 56 cpm. (auteurs)

  11. Heat exchanges in nitrogen and hydrogen boiling under pressure; Echanges thermiques dans l'azote et l'hydrogene bouillant sous pression

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-07-01

    The heat transfer between a horizontal wall and boiling nitrogen or hydrogen has been studied from atmospheric pressure to 2/3 of the critical pressure. The q = f(T) curves are rather well defined for nitrogen but more uncertain for hydrogen. In general, the measured {delta}T are inferior to those given by various authors using the wire method. The q{sub max} = f(P) more reproducible curves show for both fluids a maximum at about 0.4 P{sub cr} say 45 watt cm{sup -2} for 12.5 atm in nitrogen and 16 watt cm{sup -2} for 5.5 atm in hydrogen. Beyond, calefaction appears with a reduced dissipated power, rough reduction (90 per cent in few degrees) for nitrogen, smoother for hydrogen. (author) [French] On a etudie l'echange de chaleur entre une paroi horizontale et l'azote ou l'hydrogene bouillant depuis la pression atmospherique jusqu'au 2/3 de la pression critique. Les courbes q = f(T) sont assez bien definies pour l'azote mais accusent une marge d'incertitude pour l'hydrogene. En generale, les {delta}T mesurees sont inferieures a celles obtenues par divers auteurs utilisant la methode du fil. Les courbes plus reproductibles de q{sub max} f(P) passent par un maximum pour les deux liquides a environ 0,4 P{sub cr}, c'est-a-dire 45 watt cm{sup -2} pour 12,5 atm dans l'azote et 16 watt cm{sup -2} pour 5,5 atm dans l'hydrogene. Au-dela, la calefaction se produit avec un pouvoir dissipatif reduit, une reduction brusque pour l'azote (90 p. 100 en quelques degres) et plus reguliere pour l'hydrogene. (auteur)

  12. The General Laws of Chemical Elements Composition Dynamics in the Biosphere

    Science.gov (United States)

    Korzh, Vyacheslav D.

    2013-04-01

    The key point of investigation of the specificity of the biosphere elemental composition formation is determination of patterns of redistribution of elemental average concentrations among various phases, like solid - liquid ( the lithosphere - the hydrosphere), which occurs as a result of a global continuous processing of inert matter by living substances. Our task here is to investigate this process in the system "lithosphere - hydrosphere" in view of the integrated involvement of living material in it. This process is most active in biogeochemical barriers, i.e. in places of "the life condensation" and runs under a nonlinear regularity that has been unknown before. It is established that this process results in a general relative increase in concentrations of chemical elements in the solid phase in proportion as their prevalence in the environment is reduced. This process running in various natural systems has practically the same parameter of nonlinearity (v) approximately equal to 0.7. For proto-lithosphere -"living material" - soil v = 0.75. For river - "living material" - ocean v = 0.67. For the contemporary factual awareness level these estimations of nonlinearity indices are practically negligible. Hence, it is for the first time that the existence of a universal constant of nonlinearity of elemental composition evolution in the biosphere has been proved and its quantitative evaluation has been made. REFERENCES 1. Korzh V.D. 1974. Some general laws governing the turnover of substance within the ocean-atmosphere-continent-ocean cycle. // Journal de Recherches Atmospheriques. Vol. 8. P. 653-660. 2. Korzh V.D. 2008. The general laws in the formation of the elemental composition of the Hydrosphere and Biosphere.// J. Ecologica, Vol. XV, P. 13-21. 3. Korzh V.D. 2012. Determination of general laws of elemental composition in Hydrosphere // Water: chemistry & ecology, Journal of water science and its practical application. # 1, P.56-62.

  13. Study of the stopping power of various filters; Etude du pouvoir d'arret de differents filtres

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-07-01

    The first part is devoted to a study of aerosols obtained from the combustion of various smoke-producing compounds. A trial aerosol of which the size distribution is the closest possible to that of atmospheric dusts has been defined. The efficiency of various filters has been determined for successive increments of the dimensions and not for the whole range of its diameter distribution. The variation in the efficiency of the filtering layers as a function of the filtering speed and particle size has been studied for aerosols having particle diameters of over 0.3 {mu}. The second part describes an original method for measuring the efficiency of filters for ultra-fine particles (under 0.1 {mu}) using the fixation properties of radioactive atoms resulting from the decay of thoron. (author) [French] La premiere partie est consacree a l'etude des aerosols obtenus a partir de la combustion de divers types de fumigenes. Un aerosol d'essai, dont la repartition granulometrique se rapproche le plus possible des poussieres atmospheriques a ete defini. L'efficacite de plusieurs filtres a ete determinee pour des tranches successives de dimension et non pour l'aerosol pris dans sa totalite. La variation de l'efficacite des couches filtrantes en fonction de la taille des particules et de la vitesse de filtration a ete examinee pour des aerosols superieurs a 0,3 {mu}. La seconde partie decrit une methode originale permettant de mesurer l'efficacite des filtres pour des particules ultrafines (inferieures a 0,1 {mu}) en utilisant la propriete de fixation des atomes radioactifs des descendants du thoron. (auteur)

  14. Argon activation analysis, application to dating by the potassium-argon method; Analyse par activation de l'argon. Application a la datation par la methode potassium-argon

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-07-01

    Activation analysis using radiogenic argon-40 has been applied to rock-dating by the K-Ar method. The argon is extracted from the sample, purified, activated to saturation in a flux of 2 X 10{sup 13} neutrons/cm{sup 2} sec{sup -1} and measured by gamma spectroscopy. The sensitivity obtained is such that it is possible to measure amounts of argon corresponding to age of a few thousand years only. However since it has not been possible to measure the amount of pollution of radiogenic argon by atmospheric argon with any accuracy, the measurable age limit is in fact of the order of MY. The method has been applied to basalts from the Mont-Dore region. The results obtained are in fairly good agreement with geological, stratigraphic and paleomagnetic data. (author) [French] L'analyse par activation de l'argon 40 radiogenique a ete appliquee a la datation des roches par la methode K-Ar. L'argon est extrait de l'echantillon, purifie, active a saturation dans un flux de 2.10{sup 13} neutrons.cm{sup -2}.s{sup -1} et mesure en spectrometrie gamma. La sensibilite obtenue est telle qu'il est possible de mesurer des quantites d'argon correspondant a des ages de quelques milliers d'annees seulement. Cependant la correction de pollution de l'argon radiogenique par l'argon atmospherique n'ayant pu etre etablie avec precision, la limite d'age mesurable pratique est de l'ordre de 1 Ma. La methode a ete appliquee aux basaltes de la region du Mont-Dore. Les ages obtenus sont en assez bon accord avec les donnees geologiques, stratigraphiques et paleomagnetiques. (auteur)

  15. A contribution to the study of the mixed uranium-plutonium mono-carbides containing small quantities of zirconium; Contribution a l'etude du monocarbure d'uranium et de plutonium avec de faibles additions de zirconium

    Energy Technology Data Exchange (ETDEWEB)

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

    1970-03-01

    We have studied a mixed monocarbide, type (U,Pu)C, containing small additions of zirconium for the application as a fast neutron reactor fuel. A preliminary study was conducted on the (U,Zr)C monocarbide (Report CEA-R-3765(1). It was found that small additions of zirconium to the uranium-plutonium monocarbide improve a number of properties such as atmospheric corrosion, the hardness, and particularly the compatibility with 316 stainless steel. However, properties such as the coefficient of expansion and the melting point are only slightly changed. The relative percentage of Pu/U+Pu in the monocarbide was fixed at 20 per cent. Two processes of fabrication were employed: casting in an arc furnace, sintering, carried out after having the hydrides of the metals carburized. The metallurgical results indicate, that the above mentioned fuel might be of interest for fast neutron reactor application. (author) [French] On a etudie un combustible de type carbure (U,Pu)C pour les reacteurs a neutrons rapides. Les recherches preliminaires ont porte sur le carbure (UZr)C (rapport CEA-R-3765(1)). L'addition de faibles quantites de zirconium (3 at. pour cent) au monocarbure (U,Pu)C, ameliore certaines proprietes, commee la tenue a la corrosion atmospherique, la durete et surtout la compatibilite avec l'acier inoxydable X-18 M, Par contre le coefficient de dilatation et la densite sont peu changes. Le rapport Pu/Pu+U etait fixe a 20 pour cent. Deux procedes de fabrication ont ete etudies: l'un par fusion a l'arc, l'autre par frittage a partir de metaux hydrures. Au vu des resultats metallurgiques obtenus le carbure (U,Pu,Zr)C semble presenter un interet certain. (auteur)

  16. On the Waste Disposal Potentiality of the Atmosphere; Possibilites d'Elimination des Dechets Radioactifs dans l'Atmosphere; 041a 0412 041e 041f 0414 ; Sobre la Posibilidad de Evacuar Desechos en la Atmosfera

    Energy Technology Data Exchange (ETDEWEB)

    Small, S. H.; Storebo, P. B. [Norwegian Defence Research Establishment (Norway)

    1960-07-01

    The whole scale of atmospheric mixing, transport and removal processes is reviewed. Certain measurements indicate replacement of stratospheric air within about two years, making high-altitude disposal of radioactive waste materials even less attractive than earlier assumed. Deposition of radioactive materials is to some extent systematically non-uniform, and permissible levels of atmospheric radioactivity should be based upon the probable hazards in the most exposed regions, e.g. regions of considerable orographic precipitation. In connexion with the measurement of atmospheric radioactivity, it is pointed out that sampling techniques should cover the probable effects of gradual changes in particle sizes, and removal of particles by settling, impingement and absorption on vegetation and buildings etc. Meteorological problems in connexion with radiation monitoring and warning systems are discussed in relation to reactor operations. Technical details of relatively simple warning systems are given. (author) [French] Les auteurs examinent l'ensemble des processus suivant lesquels les dechets radioactifs sont brasses, transportes et disperses dans les couches atmospheriques. Certaines mesures indiquent que le renouvellement des masses d'air stratospheriques se fait' en moins de deux ans environ; la possibilite d'eliminer les dechets radioactifs dans les couches superieures de l'atmosphere semble donc encore moins seduisante qu'elle ne le paraissait tout d'abord. On peut dire que, dans une certaine mesure, le depot des substances radioactives s'effectue systematiquement de facon non uniforme; pour determiner le taux de radioactivite atmospherique admissible, il faut donc se baser sur les risques probables encourus dans les regions les plus exposees, par exemple dans les regions a fortes precipitations orographiques. En ce qui concerne la mesure de la radioactivite atmospherique, les techniques d'echantillonnage devraient tenir compte des consequences probables de la

  17. Influencia del hábitat en las asociaciones nictimerales de peces en una laguna costera tropical Influence of habitat type on diel fish associations in a tropical costal lagoon

    Directory of Open Access Journals (Sweden)

    Daniel Arceo-Carranza

    2010-12-01

    Full Text Available Se evaluó la abundancia y recambio de las especies ícticas que habitan en la laguna de Celestún en función de los ciclos de luz y oscuridad y del tipo de hábitats. Para ello se realizaron 6 muestreos bimestrales en una red de 4 estaciones; 2 localizadas en la boca y 2 en la zona interna de la laguna. Los sitios de cada zona comprenden un fondo con vegetación acuática y otro sin ésta (VAS, FSV. En cada sitio se registraron parámetros hidrológicos para determinar su relación con la estructura de la comunidad. Los peces se recolectaron con un chinchorro (15 × 1.5 m, 2.5cm luz de malla en un periodo diurno (10:00-3:00, crepuscular (18:00-21:00 y nocturno (02:00-05:00. Para su análisis se utilizaron diferentes estadísticos multivariados no parámetricos (NPMANOVA, NMDS, betadisper. Se encontraron diferencias en composición de especies de peces entre hábitats con VAS y FSV (F=2.6108, p=0.0114. La tasa de recambio de especies es baja entre hábitats y entre ciclos de luz-oscuridad. Los ensamblajes de peces entre hábitats son más dinámicos que nictimeralmente, debido a que las praderas de vegetación sumergida soportan un mayor número de especies por su función en la alimentación y/o como protección.The abundance and turnover of fish species inhabiting Celestún lagoon were evaluated according to day-night cycles, as well as habitat type. Bimonthly sampling was done at 4 sites of the lagoon, 2 at the mouth and 2 at the inner zone. The sites for each zone include bottoms with and without submerged aquatic vegetation (VAS, FSV. At each site hydrologic parameters were registered to determine their relationship with fish community structure. Fish specimens were collected using a beach seine (15 ×1.5 m, 2.5cm mesh at day (10:00-13:00, twilight (18:00-21:00 and night (02:00-05:00. Multivariate non-parametric (NPMANOVA, NMDS, betadisper statistics were used for the analysis. Difference in fish species were found between habitats with

  18. Consumo de forragem e desempenho de vacas Holandesas sob pastejo em gramíneas tropicais - DOI: 10.4025/actascianimsci.v29i3.549 Forage intake and performance of Holstein lactating cows fed on tropical grassland pastures - DOI: 10.4025/actascianimsci.v29i3.549

    Directory of Open Access Journals (Sweden)

    Daniel Portella Montardo

    2007-12-01

    Full Text Available Foi avaliada a estrutura das pastagens de Capim Elefante Anão (Pennisetum purpureum Schum. cv. Mott (CEA e Tifton 85 (Cynodon dactylon x Cynodon nlemfuensis (T85 e sua relação com o consumo de forragem e desempenho de vacas em lactação. O experimento foi conduzido no ano agrícola de 2004/05, em área da Escola Estadual Técnica Celeste Gobbato, em Palmeira das Missões, Estado do Rio Grande do Sul. Foram utilizadas 12 vacas-teste da raça Holandesa, alimentadas exclusivamente com as pastagens, em pastejo contínuo, distribuídas em dois piquetes por tratamento. As densidades de forragem foram mais altas no T85 que no CEA, em função da maior produção de forragem. Os estratos do dossel forrageiro mais acessíveis ao consumo pelos animais (acima de 20 e 10 cm de altura para CEA e T85, respectivamente apresentaram estruturas distintas, mas o consumo de forragem e a produção de leite foram semelhantes entre os tratamentos. A composição química destas camadas foi similar à das respectivas simulações de pastejo em ambas forrageiras, indicando a determinação da composição química nos estratos mais acessíveis ao pastejo como ferramenta útil nas inferências sobre a qualidade da forragem potencialmente consumível. Pastagens tropicais podem proporcionar produções de leite acima de 17 kg vaca-1 dia-1, mesmo sem uso de suplementação.The structure of Dwarf Elephantgrass (Pennisetum purpureum Schum. cv. Mott (DEG and Tifton 85 (Cynodon dactylon x Cynodon nlemfuensis (T85 pastures and its relation with forage intake and the performance of lactating cows were evaluated. The trial was conducted in the growth season of 2004/05, in an area belonging to the Celeste Gobbato State Technical School, in the city of Palmeira das Missões, State of Rio Grande do Sul, Brazil. Twelve Holstein cows were used as testers, fed exclusively on pasture under continuous grazing, in two paddocks per treatment. Forage density was higher on T85 than in

  19. Qualidade fisiológica e teor de lignina no tegumento de sementes de soja convencional e transgênica RR submetidas a diferentes épocas de colheita Physiological quality and lignin content in the coat seeds of conventional and RR transgenic soybean submitted to different harvest periods

    Directory of Open Access Journals (Sweden)

    Cristiane Fortes Gris

    2010-04-01

    Full Text Available Têm-se levantado à hipótese de que cultivares de soja RR possuem teores de lignina superiores aos convencionais, o que proporciona maior resistência a danos mecânicos e maior impermeabilidade do tegumento das sementes. Objetivou-se avaliar a qualidade fisiológica e o teor de lignina no tegumento das sementes de soja convencional e RR colhidas em três épocas, em Lavras-MG. Para tanto, as sementes colhidas nos estádios R7, R8 e após 20 dias de retardamento da colheita (R8+20, foram submetidas aos testes para avaliação da qualidade fisiológica e teor de lignina. As cultivares convencionais e RR avaliadas foram: BRS 133 vs BRS 245 RR, BRS 134 vs BRS 247 RR, Conquista vs Valiosa RR, Celeste vs Baliza RR e Jataí vs Silvânia RR. Foram realizados os testes de peso de mil sementes, germinação, envelhecimento acelerado, condutividade elétrica, dano mecânico, índice de velocidade de emergência, germinação após a imersão das sementes em água e teor de lignina no tegumento de sementes. Com exceção do teor de lignina no tegumento de sementes para o contraste Jataí vs Silvânia RR, não foram observadas diferenças entre os materiais RR e convencional, tendo, neste caso, a cv Silvânia RR apresentado resultados superiores aos da convencional. No entanto, houve diferença de comportamento entre os cultivares quanto à tolerância ao retardamento da colheita. Observou-se redução significativa na porcentagem de germinação e vigor das sementes avaliadas com o retardamento da colheita.One has raised the hypothesis that the RR soybean cultivars posses lignin contents higher than those of the conventional ones. The present work was conducted with the purpose of evaluating the physiological quality and lignin content in the coat of the conventional and RR soybean seeds collected in three times in Lavras-MG. To that end, the seeds collected at stages R7, R8 and after 20 days of collection delay (R8+20 were submitted to the tests for

  20. Percepção astronómica de um grupo de alunos do ensino médio de uma escola da rede estadual de São Paulo

    Science.gov (United States)

    de Oliveria, E. F.; Voelzke, M. R.

    2009-03-01

    Sendo a Astronomia uma das cièncias mais antigas da humanidade, e considerando sua importáncia histórica e cultural, é de extrema releváncia que tópicos relacionados a ela sejam tratados nas escolas. Embora os Parámetros Curriculares Nacionais do Ensino Médio (PCN-EM) e as Orientaçiacute;es Complementares aos Parámetros (PCN+) apontem a importáncia de uma abordagem significativa de conceitos relacionados à Astronomia nas aulas de Física, muitos estudantes terminam o Ensino Médio (EM) sem compreender a razão de certos acontecimentos de origem celeste, ainda que estes façam parte de seu cotidiano e sejam alvos da curiosidade natural dos jovens. Da observação dessa curiosidade em alunos de uma escola pública paulista, na cidade de Suzano, surgiu o interesse em investigar os conhecimentos básicos em Astronomia dos alunos do Ensino Médio desta escola, constituindo-se este como principal objetivo desta pesquisa. Para tanto foi elaborado um questionário de múltipla escolha aplicado inicialmente a 34 alunos do primeiro ano e, posteriormente, a mais 310, distribuídos entre as très séries do Ensino Médio dos períodos matutino e noturno. Dessa forma, observou-se que 73,9% dos estudantes identificaram o Sol como sendo uma estrela, 67,1% mostraram compreender a sucessão entre dia e noite e 52,3% relacionaram o Big Bang à origem do Universo. Em contrapartida, apenas 34,5% relacionaram as estaçíes do ano à inclinação do eixo de rotação da Terra, 21,3% indicaram a influència gravitacional simultánea da Lua e do Sol como responsável pelo fenòmeno das marés, 24,5% indicaram corretamente quais são os objetos celestes mais próximos da Terra, 36,1% identificaram ano-luz como uma medida de distáncia e 34,2% reconheceram as estrelas cadentes como meteoros, evidenciando-se assim o pequeno discernimento dos estudantes quanto aos fenòmenos e termos astronòmicos do cotidiano. Além disso, foram comparadas as respostas de alun! os de diferentes s

  1. Fish larvae and juveniles checklist (Pisces from the northern Yucatán Peninsula, Mexico, with 39 new records for the region Listado de larvas y juveniles de peces del norte de la península de Yucatán, México, con 39 nuevos registros para la región

    Directory of Open Access Journals (Sweden)

    Víctor García-Hernández

    2009-04-01

    Full Text Available A taxonomic checklist for fish larvae and juveniles occurring at Yalahau (June 2001-May 2002, Celestún (July 1994-June 1995, Chelem (July 1999-June 2000 and Río Lagartos (November 1996- October 1997 lagoons located in the northern part of the Yucatán Peninsula is presented. Sampling was carried out for 5 minutes using a zooplankton net for larvae, while a Renfro net was hauled for 50 m2 to capture juveniles. This work aims to provide the current state of the taxonomic composition and general distribution for 34 377 fish larvae and juveniles. Our samples represent 2 classes, 17 orders, 45 families, 83 genera and 117 species were caught, including 39 new records, where 24 have been found only in the Gulf of Mexico, 3 in the Caribbean Sea, and 90 are common to both regions. This study updates and increases the number of species in larval and juvenile stages previously reported. It was found that early reef larval stages were more abundant towards the East of the Yucatán Peninsula and less to the West. The high number of shared species (90 suggests that the northern region of the Yucatán Peninsula is a transition zone for fish larvae and juveniles between the Gulf of Mexico and the Caribbean Sea.Se presenta un listado taxonómico de larvas y juveniles de peces de las lagunas de Yalahau (junio 2001-may 2002, Celestún (julio 1994-junio 1995, Chelem (julio 1999-junio 2000 y Río Lagartos (noviembre1996- octubre 1997 del norte de la península de Yucatán. Se actualiza e incrementa el registro en el número de especies del lugar reportado en estudios previos y se hacen observaciones sobre la distribución general de las larvas y juveniles de peces del área. Los muestreos se realizaron durante 5 minutos con una red de zooplancton para las larvas de peces y una red Renfro para los juveniles cubriendo un área de 50 m2. Se registraron 2 clases, 17 órdenes, 45 familias, 83 géneros y 117 especies, incluyendo a 39 nuevos registros, y de las cuales 24

  2. Report of activity, 1995 - 1996; Rapport d`activite, 1995 - 1996

    Energy Technology Data Exchange (ETDEWEB)

    Aguer, Pierre [Centre d`Etudes Nucleaires, Bordeaux-1 Univ., 33 Gradignan (France)

    1997-06-01

    This Report of activity displays the work developed at Centre d`Etude Nucleaires de Bordeaux-Gradignan (CENBG) in the period 1995-1996. A number of 68 short progress notes are presented in the fields of Cosmic particles (3), Nuclear Astrophysics (4), High Spins-Large Deformations (8), Basic Interactions (9), Exotic Nuclei (10), Hybrid Systems (4), Theoretical Physics (28), Cellular Microanalysis by means of Nuclear Probes (3) and Technical Development (3). The main problems attacked at CENBG, established as orientations by scientific board of IN2P3 (CENBG is a UMR of Bordeaux-1 Univ. and CNRS-IN2P3) are the following: the research of Majorana/Dirac nature of neutrino (in the framework of NEMO Experiment) in relation with the problem of origin of mass in the Universe and the cosmological puzzle of dark matter, the investigation of the origin of high energy (20 to 200 GeV) cosmic radiation (in the framework of CELESTE Experiment), the study of extreme issues in nuclear structure as high spin states and super deformation (in the framework of DIAMANT and SAPHIRE Experiments) and the study of exotic (far-off-stability-line) high-isospin nuclei, nuclear dynamics and hadron (sub-nucleon degrees of freedom) physics, extensive cosmic showers and the physics of free electron lasers. To these issues one should add two recent activities which will be largely developed in the near future. The first is the physics of hybrid reactors and the nuclear burning (nuclear transmutation) of the radioactive wastes and the second is the application of the Van de Graaff microprobe method in biological investigations. This report is completed by a presentation of the most recent technical developments at CENBG

  3. La actividad poética de Neruda en los años treinta

    Directory of Open Access Journals (Sweden)

    Teodosio Femández

    2007-12-01

    Full Text Available Aunque fue en 1933 cuando Luis Enrique Délano, después compañero de tareas diplomáticas en Madrid y en México, consiguió que la Empresa Letras publicara en Santiago de Chile El hondero entusiasta, no ha de olvidarse que ese libro fue el·efecto ya lejano de la «embriaguez de estrellas, celeste, cósrnica»1 que en 1923, bajo el influjo del poeta uruguayo Carlos Sabat Ercasty, Pablo Neruda sintió en una noche de su Temuco natal. Tras los cinco difíciles años que había vivido como cónsul honorario de su país en distintos lugares del Asia oriental, Neruda había regresado en abril de 1932, y había dedicado sus primeros esfuerzos a preparar la nueva edición de Veinte poemas de amor y una canción desesperada que la Editorial Nascimento publicó en Santiago en junio del mismo año, con la reelaboración de varios poemas, en especial el 2 y el 4, y la sustitución del 9 por otro escrito en aquellas fechas. Antes de llegar ya había completado el volumen que en 1933 constituyó la edición inicial de Residencia en la tierra, también realizada por Nascimento tras los fracasados esfuerzos de Rafael Alberti para que se publicara en España o en Francia, allí con la colaboración de Alejo Carpentier, cuando en París éste dirigía para la argentina Elvira de Alvear la revista Imán, cuyo único número apareció el 1 de abril de 1931.

  4. Biodegradation of radioactive organic liquid waste from spent fuel reprocessing

    International Nuclear Information System (INIS)

    Ferreira, Rafael Vicente de Padua

    2008-01-01

    The research and development program in reprocessing of low burn-up spent fuel elements began in Brazil in 70's, originating the lab-scale hot cell, known as Celeste located at Nuclear and Energy Research Institute, IPEN - CNEN/SP. The program was ended at the beginning of 90's, and the laboratory was closed down. Part of the radioactive waste generated mainly from the analytical laboratories is stored waiting for treatment at the Waste Management Laboratory, and it is constituted by mixture of aqueous and organic phases. The most widely used technique for the treatment of radioactive liquid wastes is the solidification in cement matrix, due to the low processing costs and compatibility with a wide variety of wastes. However, organics are generally incompatible with cement, interfering with the hydration and setting processes, and requiring pre -treatment with special additives to stabilize or destroy them. The objective of this work can be divided in three parts: organic compounds characterization in the radioactive liquid waste; the occurrence of bacterial consortia from Pocos de Caldas uranium mine soil and Sao Sebastiao estuary sediments that are able to degrade organic compounds; and the development of a methodology to biodegrade organic compounds from the radioactive liquid waste aiming the cementation. From the characterization analysis, TBP and ethyl acetate were chosen to be degraded. The results showed that selected bacterial consortia were efficient for the organic liquid wastes degradation. At the end of the experiments the biodegradation level were 66% for ethyl acetate and 70% for the TBP. (author)

  5. MEDICINA DEL RENACIMIENTO ESPAÑOL

    Directory of Open Access Journals (Sweden)

    Adolfo de Francisco Zea

    1984-11-01

    Full Text Available

    Arnold Toynbee, historiador y filósofo inglés, en su "Estudio de la Historia" postula la tesis de que las civilizaciones crecen y se desarrollan en la medida en que son capaces de responder con éxito a los desafíos que se les presentan.

    Cuando esto no ocurre así, como es el caso de los nómadas mongoles del Asia Central, que tuvieron que enfrentarse a las difíciles exigencias de la vida en las estepas, terminan transformándose en esclavos de su medio ambiente lo que las torna incapaces de cualquier
    actividad creadora.

    No ocurre lo mismo con la mayoría de las civilizaciones occidentales, en las cuales cada reto ha determinado una respuesta exitosa que a la vez provoca desequilibrios que requieren nuevos ajustes creativos. Este impulso o "elan" del crecimiento, para usar la terminología de Bergson, está ejemplificado en el mito de Prometeo que atraviesa con su antorcha las esferas celestes para robar a Zeus el fuego para el hombre, y persuadirle de la necesidad de permitir el desarrollo perpetuo de la Humanidad.
    En el centro de una miniatura del siglo XV, aparece Prometeo animando la figura inerte del Hombre en el Paraíso. El fuego prometeico es una fuerza que da la vida, pero además simboliza el ardor de la curiosidad intelectual y del conocimiento, lo cual lleva consigo implícito el fruto peligroso de esa misma curiosidad...

  6. Acceso a la educación en salud y su potencial en la disminución de la incidencia de diarrea infantil en las poblaciones costeras de Yucatán, México

    Directory of Open Access Journals (Sweden)

    Rubén Solís

    2016-02-01

    Full Text Available Introducción: La educación en salud o pláticas en el ámbito institucional mitiga la incidencia de diarrea infantil. Yucatán es el estado con las mayores tasas de incidencia de diarreas a nivel nacional; el impacto de las pláticas, como parte de un programa de salud, en la incidencia de diarreas ha sido insuficientemente estudiado. Objetivo: Analizar el rol del acceso a las pláticas para prevenir la incidencia de diarreas infantiles. Metodología: Se utilizó el muestreo de encuestas en 151 hogares, se encontró a 187 niños menores de cinco años de edad. El estudio se realizó en tres segmentos muestrales de la zona costera, con diferentes condiciones ambientales: Progreso (puerto urbano concentrado, Celestún (reserva biosfera, turismo, urbanizada y Río Lagartos (turismo, reserva biosfera rural. Se estimó la tasa de prevalencia lápsica de diarrea, los casos fueron las diarreas ocurridas en los 15 días inmediatos previos a la encuesta. Se hizo análisis descriptivos, bivariados, estratificados y la regresión logística binaria. Resultados: Se registró una tasa de prevalencia lápsica de 13.37% (n=25 casos. El análisis logístico multivariado mostró el impacto protector significativo de las pláticas (=-2.105; RM=0.163; y = 0.018 con un efecto que equivale a 6.25 veces menos riesgo de presentar episodios diarreicos. Conclusión: Las pláticas, como política de salud, tienen impacto en la disminución de las diarreas; esto sucede en especial si se llevan a cabo entre los beneficiarios de los programas sociales.

  7. Understanding kangaroo care and its benefits to preterm infants

    Directory of Open Access Journals (Sweden)

    Campbell-Yeo ML

    2015-03-01

    Full Text Available Marsha L Campbell-Yeo,1–4 Timothy C Disher,1 Britney L Benoit,1 C Celeste Johnston,2,4,5 1School of Nursing, Dalhousie University, 2Department of Pediatrics, IWK Health Centre, 3Department of Psychology and Neuroscience, Dalhousie University, 4Centre for Pediatric Pain Research, IWK Health Centre, Halifax, NS, 5Ingram School of Nursing, McGill University, Montréal, QC, Canada Abstract: The holding of an infant with ventral skin-to-skin contact typically in an upright position with the swaddled infant on the chest of the parent, is commonly referred to as kangaroo care (KC, due to its simulation of marsupial care. It is recommended that KC, as a feasible, natural, and cost-effective intervention, should be standard of care in the delivery of quality health care for all infants, regardless of geographic location or economic status. Numerous benefits of its use have been reported related to mortality, physiological (thermoregulation, cardiorespiratory stability, behavioral (sleep, breastfeeding duration, and degree of exclusivity domains, as an effective therapy to relieve procedural pain, and improved neurodevelopment. Yet despite these recommendations and a lack of negative research findings, adoption of KC as a routine clinical practice remains variable and underutilized. Furthermore, uncertainty remains as to whether continuous KC should be recommended in all settings or if there is a critical period of initiation, dose, or duration that is optimal. This review synthesizes current knowledge about the benefits of KC for infants born preterm, highlighting differences and similarities across low and higher resource countries and in a non-pain and pain context. Additionally, implementation considerations and unanswered questions for future research are addressed. Keywords: kangaroo care, skin-to-skin contact, infant, preterm, review

  8. A instrução pelo riso em Santo Agostinho - doi: 10.4025/actascieduc.v32i2.10429

    Directory of Open Access Journals (Sweden)

    Marcia Maria Medeiros

    2010-12-01

    Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabela normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Santo Agostinho autor de várias obras, entre elas a que originou este artigo, intitulada A Instrução aos Catecúmenos, e referenda partindo do pressuposto de que o ser humano está em peregrinação nesse mundo rumando para a Jerusalém Celeste. No livro analisado neste artigo, Santo Agostinho mostra como o catequista deve se utilizar da alegria e do riso enquanto elementos que facilitem o ensino da religião cristã aqueles e aquelas que pretendem fazer parte dela. A partir desse processo é possível perceber como o riso possui uma lógica de fundamental importância no que tange ao funcionamento das práticas sociais e culturais de um determinado grupo humano em um determinado momento histórico, servindo como ferramenta para ações práticas em torno de vários assuntos, inclusive pedagógicas.  

  9. Qualidade fisiológica e composição centesimal de soja convencional e transgênica produzidas em diferentes épocas e pulverizadas com glifosato

    Directory of Open Access Journals (Sweden)

    Cristiane Fortes Gris

    2014-09-01

    Full Text Available Objetivou-se avaliar a composição centesimal de sementes de soja RR e convencional produzidas em safra verão e inverno, e avaliar sementes de soja RR submetidas à pulverização com glifosato, correlacionando-as com a qualidade fisiológica das sementes. As sementes foram produzidas na UFLA, Lavras-MG, onde foram realizados os dois ensaios: Produção de sementes em épocas de semeadura, em blocos casualizados com quatro repetições, avaliando-se 10 cultivares, e o ensaio de aplicação do herbicida glifosato, implantado com 5 cultivares em parcelas subdivididas com quatro repetições. Todos os tratos culturais foram realizados de acordo com a necessidade da cultura. As análises de qualidade fisiológica foram realizadas na UFLA e as análises bromatológicas no IFSULDEMINAS Câmpus Muzambinho. No ensaio épocas de semeadura, dentre os contrastes avaliados, observou-se que os contrastes entre as cultivares Jataí vs Silvânia RR e Celeste vs Baliza RR apresentaram maior número de diferenças significativas dentre as variáveis estudadas. Por outro lado, no ensaio com aplicação de glifosato, observou-se diferença significativa somente para cultivar Baliza RR, com relação à condutividade elétrica. Tais resultados mostram que existem algumas diferenças em composição centesimal e qualidade de sementes, porém não são consistentes a ponto de diferenciar, de forma geral, as cultivares convencionais de suas versões transgênicas RR.

  10. Acceso a la educación en salud y su potencial en la disminución de la incidencia de diarrea infantil en las poblaciones costeras de Yucatán, México

    Directory of Open Access Journals (Sweden)

    Rubén Solís

    2015-01-01

    Full Text Available Introducción: La educación en salud o pláticas en el ámbito institucional mitiga la incidencia de diarrea infantil. Yucatán es el estado con las mayores tasas de incidencia de diarreas a nivel nacional; el impacto de las pláticas, como parte de un programa de salud, en la incidencia de diarreas ha sido insuficientemente estudiado. Objetivo: Analizar el rol del acceso a las pláticas para prevenir la incidencia de diarreas infantiles. Metodología: Se utilizó el muestreo de encuestas en 151 hogares, se encontró a 187 niños menores de cinco años de edad. El estudio se realizó en tres segmentos muestrales de la zona costera, con diferentes condiciones ambientales: Progreso (puerto urbano concentrado, Celestún (reserva biosfera, turismo, urbanizada y Río Lagartos (turismo, reserva biosfera rural. Se estimó la tasa de prevalencia lápsica de diarrea, los casos fueron las diarreas ocurridas en los 15 días inmediatos previos a la encuesta. Se hizo análisis descriptivos, bivariados, estratificados y la regresión logística binaria. Resultados: Se registró una tasa de prevalencia lápsica de 13.37% (n=25 casos. El análisis logístico multivariado mostró el impacto protector significativo de las pláticas (B=-2.105; RM=0.163; y p= 0.018 con un efecto que equivale a 6.25 veces menos riesgo de presentar episodios diarreicos. Conclusión: Las pláticas, como política de salud, tienen impacto en la disminución de las diarreas; esto sucede en especial si se llevan a cabo entre los beneficiarios de los programas sociales.

  11. Complement to the 1999-2000 progress report; Complement au rapport d'activite 1999-2000

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    Among a lot of achievements relevant to INIS we can note: -) the status of the work on GLAST (gamma-ray large area space telescope) and on the Celeste telescope; -) the study of the energy and angular distributions of the fast outgoing electron beam produced in the interaction of a laser beam with a thin plastic foil and a gas jet; -) the investigation of the excitation of the 76 eV energy level of U{sup 235} by a YAG laser radiation; -) the feasibility study of a dating method of wines based on the gamma spectroscopy of specific rays of K{sup 40} and Cs{sup 137}; -) the study of nuclei beyond the proton drip line by determining the missing mass spectrum from complete kinematics measurements of the reaction products; -) the beta decay half-lives of proton-rich Kr{sup 78} fragments have been determined for all nuclei between Z = 27 and 36; -) a beta decay scheme is proposed for P{sup 26} and S{sup 27} including beta delayed one and two proton emission and gamma ray spectroscopy; -) the observation of the 2-proton emission decay of the Fe{sup 45} fundamental state; -) the measurement of the radiative capture cross-section of I{sup 129}; -) the measurement of the fission cross-section of U{sup 233} induced by fast neutrons; -) the investigation of intermediate mass fragments observed in coincidence with 2 correlated fission fragments following incomplete fusion in C{sup 12} + Th{sup 232} at E/A = 16 and 22 MeV; and -) the status of the single ion irradiation system used for the irradiation of biological samples. (A.C.)

  12. Shen: una psicología holística de la medicina china tradicional

    Directory of Open Access Journals (Sweden)

    Yidi Páez Casadiego

    2015-03-01

    Full Text Available La palabra Shen denota mente, consciencia, estados mentales, pero debido a su carácter ideo-pictográfico, connota un nivel de metáfora que convierte su traducción en un ejercicio hermenéutico, sobre todo cuando hace parte de un estilo de pensamiento que se estructura discursiva y poéticamente con otras palabras-metáfora. La metáfora principal del sistema es Tai-Chi ("gran respiración celeste", "la gran energía cósmica", la "energía del todo", etc., a partir de la cual se construye un discurso médico-ético-filosófico. La palabra Shen se refiere a un tipo de "energía" (chi que permite interpretar de manera holística los mecanismos generadores de síntomas, la descripción de sus signos, sus abordajes terapéuticos, y la condición ética del terapeuta en la relación médico-paciente. A través del Shen se integran de manera transdisciplinaria las esferas del Tai-Chi natural, con un tai-chi mental-político-societal. A partir de estas consideraciones, se propone la medicina tradicional china como una medicina-psicológica, por su propedéutica y metodología holística, y por su visión psicosomática, en sentido epistemológico. Esta medicina-psicológica suscita preguntas frente a nuestras convenciones institucionales y seguridades discursivas de una "psicología médica" que se percibe, cada vez más, separada disciplinariamente del saber psicológico.

  13. Report of activity, 1995 - 1996

    International Nuclear Information System (INIS)

    Aguer, Pierre

    1997-06-01

    This Report of activity displays the work developed at Centre d'Etude Nucleaires de Bordeaux-Gradignan (CENBG) in the period 1995-1996. A number of 68 short progress notes are presented in the fields of Cosmic particles (3), Nuclear Astrophysics (4), High Spins-Large Deformations (8), Basic Interactions (9), Exotic Nuclei (10), Hybrid Systems (4), Theoretical Physics (28), Cellular Microanalysis by means of Nuclear Probes (3) and Technical Development (3). The main problems attacked at CENBG, established as orientations by scientific board of IN2P3 (CENBG is a UMR of Bordeaux-1 Univ. and CNRS-IN2P3) are the following: the research of Majorana/Dirac nature of neutrino (in the framework of NEMO Experiment) in relation with the problem of origin of mass in the Universe and the cosmological puzzle of dark matter, the investigation of the origin of high energy (20 to 200 GeV) cosmic radiation (in the framework of CELESTE Experiment), the study of extreme issues in nuclear structure as high spin states and super deformation (in the framework of DIAMANT and SAPHIRE Experiments) and the study of exotic (far-off-stability-line) high-isospin nuclei, nuclear dynamics and hadron (sub-nucleon degrees of freedom) physics, extensive cosmic showers and the physics of free electron lasers. To these issues one should add two recent activities which will be largely developed in the near future. The first is the physics of hybrid reactors and the nuclear burning (nuclear transmutation) of the radioactive wastes and the second is the application of the Van de Graaff microprobe method in biological investigations. This report is completed by a presentation of the most recent technical developments at CENBG

  14. Prometeu e Pandora entre o espelho e a máscara ou Fantasia, ordem e mistério no moinho do sentido (Notas sobre Mito e Ideologia

    Directory of Open Access Journals (Sweden)

    Eduardo Diatahy Bezerra de Menezes

    1985-07-01

    Full Text Available (primeiro parágrafo do texto   PROMETEU (= "pensamento previdente". Foi um gigante cuja força era temida por Zeus. Profeta, inventor, ele criou o primeiro homem com um bloco de argila misturado com água; e foi tal a sua habilidade que Atena, maravilhada, arrebatou-o para os céus, a fim de que ali escolhesse o que julgasse necessário à perfeição de sua obra. Lá chegando, Prometeu aproximou-se do Sol, roubou uma cen-telha, que era privilégio dos imortais, e ocultou-a na haste de uma férula. De retorno à terra, ofereceu o fogo celeste ao homens que, em sua ausência, haviam-se multiplicado. Irritado com seus crimes, Zeus decidiu vingar-se dos mortais e de Prometeu. Assim, ordenou a Hefestos que conduzisse Prometeu ao alto do monte Cáucaso e aí o acorrentasse a um rochedo, onde, cada dia, durante séculos, uma águia vinha roer-lhe o fígado, que renascia sem cessar. Mas, após 30 anos de atrozes sofrimentos, ele foi libertado por Héracles, que matara a ave de rapina. Todavia, Zeus lhe impôs a obrigação de levar sempre no dedo um anel de ferro ligado a um fragmento de rocha. Posteriormente, Prometeu adquiriu a imortali-dade, cedida pelo centauro Quiron

  15. Complement to the 1999-2000 progress report

    International Nuclear Information System (INIS)

    2000-01-01

    Among a lot of achievements relevant to INIS we can note: -) the status of the work on GLAST (gamma-ray large area space telescope) and on the Celeste telescope; -) the study of the energy and angular distributions of the fast outgoing electron beam produced in the interaction of a laser beam with a thin plastic foil and a gas jet; -) the investigation of the excitation of the 76 eV energy level of U 235 by a YAG laser radiation; -) the feasibility study of a dating method of wines based on the gamma spectroscopy of specific rays of K 40 and Cs 137 ; -) the study of nuclei beyond the proton drip line by determining the missing mass spectrum from complete kinematics measurements of the reaction products; -) the beta decay half-lives of proton-rich Kr 78 fragments have been determined for all nuclei between Z = 27 and 36; -) a beta decay scheme is proposed for P 26 and S 27 including beta delayed one and two proton emission and gamma ray spectroscopy; -) the observation of the 2-proton emission decay of the Fe 45 fundamental state; -) the measurement of the radiative capture cross-section of I 129 ; -) the measurement of the fission cross-section of U 233 induced by fast neutrons; -) the investigation of intermediate mass fragments observed in coincidence with 2 correlated fission fragments following incomplete fusion in C 12 + Th 232 at E/A = 16 and 22 MeV; and -) the status of the single ion irradiation system used for the irradiation of biological samples. (A.C.)

  16. Energy potential of the Sea of Cortes; Potencial energetico del Mar de Cortes

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Gonzalez, Jose [Universidad Nacional Autonoma de Mexico (UNAM), Mexico, D.F. (Mexico)

    2006-07-01

    The increasing energy requirements, due to the excessive population growth in the world and its dependency to electronic devises in their daily life, fruit of the technological advances, have forced to different organisms as much public as private from several nations to look for alternating energy sources that are clean (that does not contaminate the environment) and relatively cheap that can face these requirements. One of these sources is, without doubt the ocean, since in it concentrates the transferred energy of the sun and the wind and the forces of attraction of the celestial bodies. In this work a quantification of the energy potential of the tides in the Sea of Cortes is presented in a practical way, taking advantage of the important unevenness of high water and low tide that appears in the North part of it, using the principles which govern the generation of a hydroelectric power station, since the operation and the equipment used are practically the same. [Spanish] Los crecientes requerimientos de energia, debido al crecimiento excesivo de poblacion en el mundo y su dependencia a dispositivos electronicos en su vida cotidiana, fruto del avance tecnologico, han obligado a diferentes organismos tanto publicos como privados de varias naciones a buscar fuentes alternas de energia que sean limpias (que no contaminen el medio ambiente) y relativamente baratas que puedan hacer frente a estos requerimientos. Una de estas fuentes es sin lugar a dudas el oceano ya que en el se concentra la energia transferida del sol y el viento y las fuerzas de atraccion de los cuerpos celestes. En este trabajo se presenta de manera practica una cuantificacion del potencial energetico de las mareas en el mar de Cortes, aprovechando el importante desnivel de pleamar y bajamar que se presenta en la parte norte del mismo, utilizando los principios que rigen la generacion de una central hidroelectrica, ya que, el funcionamiento y el equipo utilizado es practicamente es el mismo.

  17. Prevalence and Correlates of ‘Agua Celeste’ Use among Female Sex Workers who Inject Drugs in Ciudad Juarez, Mexico

    Science.gov (United States)

    Morris, Meghan D.; Case, Patricia; Robertson, Angela M.; Lozada, Remedios; Vera, Alicia; Clapp, John D.; Medina-Mora, Maria Elena; Strathdee, Steffanie A.

    2011-01-01

    Background Agua celeste, or “heavenly water,” is the street name for a sky-blue colored solvent reportedly inhaled or ingested to produce an intoxicating effect. Study aims were to (1) describe prevalence of Agua Celestse (AC) use, and (2) identify correlates of lifetime and recent use of AC use among female sex workers who also inject drugs (FSW-IDUs) in northern Mexico. Methods Between 2008 and 2010, baseline data from FSW-IDUs ≥ 18 years old living in Tijuana or Ciudad Juarez participating in a longitudinal behavioral intervention were analyzed using logistic regression. Results Among 623 FSW-IDUs (307 from Tijuana and 316 from Ciudad Juarez (CJ)), 166 (26%) reported ever using AC, all of whom lived in CJ. Among the CJ sample, lifetime prevalence of AC use was 53%, median age of first use was 16 years (IQR: 14–23), and 10% reported it as their first abused substance. Ever using AC was independently associated with ever being physically abused and younger age, and was marginally associated with initiating injection drug use and regular sex work at age eighteen or younger. Among those ever using AC, 70/166 (42.2%) reported using it within the last 6 months, which was independently associated with using drugs with clients before or during sex, being on the street more than 8 hours per day, and younger age. Discussion We observed considerable geographic variation in the use of AC in northern Mexico. Future studies exploring factors influencing use, its precise formulation(s), and its potential health effects are needed to guide prevention and treatment. PMID:21441001

  18. HYDROGEOLOGY AND CONCEPTUAL MODEL OF THE KARSTIC COASTAL AQUIFER IN NORTHERN YUCATAN STATE, MEXICO

    Directory of Open Access Journals (Sweden)

    Miguel J Villasuso-Pino

    2011-04-01

    Full Text Available The coastal zone of northern Yucatan Peninsula (YP is mainly constituted by Tertiary limestones, covered by Pleistocen limestones, where there exist swamps and estuary systems, locally called “rías”, with mouths connecting them to the sea and hence being a way for an important amount of groundwater to discharge, like in Ría Lagartos and Celestún. These limestones have karstic layers located at depths from 8 to 16 meters below terrain surface.  It is in these layers where groundwater mainly flows toward coast, passing below the sand dune and discharging in the sea in the form of submarine springs which in many cases manifest themselves on the marine surface depending on the hydraulic or piezometric fresh water head. The width of the superficial limestone within this coastal fringe, called “caliche”, varies from 5 to 10 kilometers in the study zone (Chuburna-Progreso-Chicxulub.  Its permeability is extremely low, so it constitutes a confining layer that impedes superficial waters to percolate toward groundwater.  The hydraulic head of the groundwater below this confining layer is over the mean sea level and also over the swamp water level, coastal lagoons and estuaries. There are two important hydrological phenomena that occur in this coastal fringe: 1 There is no recharge to the aquifer (groundwater due to limestone rock outcrops is impermeable or semipermeable; and 2 groundwater pressure is not lost, nor saline interfase is rised if the superficial layer is broken.  The groundwater pollution vulnerability within this coastal fringe is less than that for the superficial saline waters of swamps and estuaries, because of caliche’s low intrinsic permeability that impedes percolation.

  19. Complement to the 1999-2000 progress report; Complement au rapport d'activite 1999-2000

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    Among a lot of achievements relevant to INIS we can note: -) the status of the work on GLAST (gamma-ray large area space telescope) and on the Celeste telescope; -) the study of the energy and angular distributions of the fast outgoing electron beam produced in the interaction of a laser beam with a thin plastic foil and a gas jet; -) the investigation of the excitation of the 76 eV energy level of U{sup 235} by a YAG laser radiation; -) the feasibility study of a dating method of wines based on the gamma spectroscopy of specific rays of K{sup 40} and Cs{sup 137}; -) the study of nuclei beyond the proton drip line by determining the missing mass spectrum from complete kinematics measurements of the reaction products; -) the beta decay half-lives of proton-rich Kr{sup 78} fragments have been determined for all nuclei between Z = 27 and 36; -) a beta decay scheme is proposed for P{sup 26} and S{sup 27} including beta delayed one and two proton emission and gamma ray spectroscopy; -) the observation of the 2-proton emission decay of the Fe{sup 45} fundamental state; -) the measurement of the radiative capture cross-section of I{sup 129}; -) the measurement of the fission cross-section of U{sup 233} induced by fast neutrons; -) the investigation of intermediate mass fragments observed in coincidence with 2 correlated fission fragments following incomplete fusion in C{sup 12} + Th{sup 232} at E/A = 16 and 22 MeV; and -) the status of the single ion irradiation system used for the irradiation of biological samples. (A.C.)

  20. International Celestial Reference Frame (ICRF): mantenimiento y extensión

    Science.gov (United States)

    Ma, C.; Arias, E. F.; Eubanks, T.; Fey, A. L.; Gontier, A.-M.; Jacobs, C. S.; Sovers, O. J.; Archinal, B. A.; Charlot, P.

    A partir de enero de 1998 el sistema de referencia celeste convencional está representado por el International Celestial Reference System (ICRS) y materializado a través de las coordenadas VLBI del conjunto de radiofuentes extragalácticas que conforman el International Celestial Reference Frame (ICRF). La primera realización del ICRF, fue elaborada en 1995 por un grupo de expertos designado por la IAU, la que encomendó al International Earth Rotation Service el mantenimiento del ICRS, del ICRF y del vínculo con marcos de referencia en otras frecuencias. Una primera extensión del ICRF se realizó entre abril y junio de 1999, con el objetivo primario de proveer posiciones de radiofuentes extragalácticas observadas a partir de julio de 1995 y de mejorar las posiciones de las fuentes ``candidatas" con la inclusión de observaciones adicionales. Objetivos secundarios fueron monitorear a las radiofuentes para verificar que siguen siendo adecuadas para realizar al ICRF y mejorar las técnicas de análisis de datos. Como resultado del nuevo análisis se obtuvo una solución a partir de la cual se construyó la primera extensión del ICRF, denominada ICRF - Ext.1. Ella representa al ICRS, sus fuentes de definición se mantienen con las mismas posiciones y errores que en la primera realización del ICRF; las demás radiofuentes tienen coordenadas mejor determinadas que en ICRF; el marco de referencia se densificó con el agregado de 59 nuevas radiofuentes.

  1. Natureza e cultura na paisagem amazônica: uma experiência fotográfica com ressonâncias na cosmologia ameríndia e na ecologia histórica

    Directory of Open Access Journals (Sweden)

    Patrick Pardini

    Full Text Available Enquanto experiência artística, o projeto fotográfico "Arborescência - fisionomia do vegetal na paisagem amazônica" proporciona ao autor uma série de descobertas: a paisagem como entrelaçamento de Natureza e Cultura (a presença indireta do homem; o face a face com 'sujeitos vegetais'; as relações de continuidade, indiferenciação e equivalência entre o 'natural' (heterogêneo, espontâneo, nativo, rural e o 'cultural' (homogêneo, cultivado, exótico, urbano na experiência da paisagem vegetal; a arborescência como "imagem cósmica" (Gaston Bachelard, onde o alto (céu, luz, galhos, água celeste e o baixo (terra, sombra, raízes, água terrestre são pólos equivalentes e reversíveis. Tal experiência encontra ressonâncias na eco-cosmologia das sociedades da floresta amazônica. A cosmologia ameríndia é uma "ecologia simbólica" (Philippe Descola, pois elabora "uma complexa dinâmica de trocas e transformações entre sujeitos humanos e não humanos, visíveis e invisíveis" (Bruce Albert; a ecologia ameríndia é uma "cosmologia posta em prática" (Kaj Århem, na qual animais caçados e plantas cultivadas são 'parentes' que é preciso seduzir ou coagir. Tal modelo constitui uma forma de "socialização da natureza" (Descola, de "humanização da floresta" (Evaristo Eduardo de Miranda e de "antropização indireta" dos ecossistemas amazônicos (Descola, geradora de "matas culturais" (William Balée.

  2. Biodegradation of radioactive organic liquid waste from spent fuel reprocessing; Biodegradacao de rejeitos radioativos liquidos organicos provenientes do reprocessamento do combustivel nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Rafael Vicente de Padua

    2008-07-01

    The research and development program in reprocessing of low burn-up spent fuel elements began in Brazil in 70's, originating the lab-scale hot cell, known as Celeste located at Nuclear and Energy Research Institute, IPEN - CNEN/SP. The program was ended at the beginning of 90's, and the laboratory was closed down. Part of the radioactive waste generated mainly from the analytical laboratories is stored waiting for treatment at the Waste Management Laboratory, and it is constituted by mixture of aqueous and organic phases. The most widely used technique for the treatment of radioactive liquid wastes is the solidification in cement matrix, due to the low processing costs and compatibility with a wide variety of wastes. However, organics are generally incompatible with cement, interfering with the hydration and setting processes, and requiring pre -treatment with special additives to stabilize or destroy them. The objective of this work can be divided in three parts: organic compounds characterization in the radioactive liquid waste; the occurrence of bacterial consortia from Pocos de Caldas uranium mine soil and Sao Sebastiao estuary sediments that are able to degrade organic compounds; and the development of a methodology to biodegrade organic compounds from the radioactive liquid waste aiming the cementation. From the characterization analysis, TBP and ethyl acetate were chosen to be degraded. The results showed that selected bacterial consortia were efficient for the organic liquid wastes degradation. At the end of the experiments the biodegradation level were 66% for ethyl acetate and 70% for the TBP. (author)

  3. Molten salt oxidation as a technique for decommissioning: selection of low melting point salt mixtures

    International Nuclear Information System (INIS)

    Lainetti, Paulo E.O.; Garcia, Vitor F.; Benvegnu, Guilherme

    2013-01-01

    During the 70 and 80 years, IPEN built several facilities in pilot scale, destined to the technological domain of the Nuclear Fuel Cycle. In the nineties, radical changes in the Brazilian nuclear policy determined the interruption of the activities and the shut-down of pilot plants. Nowadays, IPEN has been facing the problem of the dismantling and decommissioning of its Nuclear Fuel Cycle old facilities. The facility CELESTE-I of the IPEN is a laboratory where reprocessing studies were accomplished during the decade of 80 and in the beginning of the 90s. The last operations occurred in 92-93. The research activities generated radioactive wastes in the form of organic and aqueous solutions of different compositions and concentrations. For the treatment of these liquid wastes it was proposed a study of waste thermal decomposition based on the molten salt oxidation process.Decomposition tests of different organic wastes have been performed in laboratory equipment developed at IPEN, in the range of temperatures of 900 to 1020 deg C, demonstrating the complete oxidation of the compounds. The reduction of the process temperatures would be of crucial importance. Besides this, the selection of lower melting point salt mixtures would have an important impact in the reduction of equipment costs. Several experiments were performed to determine the most suitable salt mixtures, optimizing costs and melting temperatures as low as possible. This paper describes the main characteristics of the molten salt oxidation process, besides the selection of salt mixtures of binary and ternary compositions, respectively Na 2 CO 3 - NaOH and Na 2 CO 3 - K 2 CO 3 -Li 2 CO 3 . (author)

  4. ESTUDOS DE NARRATIVAS SOBRE MEMÓRIAS DE ALFABETIZAÇÃO: ALGUMAS CONSIDERAÇÕES SOBRE LETRAMENTO E NUMERAMENTO

    Directory of Open Access Journals (Sweden)

    Maira Bartira Kaufmann

    2015-08-01

    Full Text Available Apresentamos, a partir do presente artigo, alguns dos resultados parciais do projeto de pesquisa “Linguagem e Educação Matemática para a Educação Básica: um estudo de experiências pedagógicas”, que tem como objetivo geral estudar a formação de professores e suas experiências pedagógicas nas escolas de Educação Básica. O referencial teórico está concebido, principalmente, a partir dos estudos de Jorge Larrosa, Angela Kleiman e Maria Celeste Souza em relação aos conceitos de narrativa, letramento e numeramento, respectivamente. A produção e discussão de dados, por sua vez, se deu a partir de encontros quinzenais com o grupo da pesquisa, constituído por acadêmicos de cursos da graduação da UNISC, por mestrandos do PPGEdu/UNISC e por professores da rede pública estadual de ensino. Para a escrita deste texto, entretanto, consideramos as narrativas de dez professores participantes do Pacto Nacional pela Alfabetização na Idade Certa – PNAIC acerca de suas memórias de alfabetização, buscando compreender de que forma os conceitos de letramento e numeramento eram apresentados nos enunciados. A partir da análise do material, percebemos que o processo de alfabetização demonstra um distanciamento dos campos da vida social, estando muito mais associado ao ensino de práticas e à aprendizagem de habilidades individuais de escrita e leitura.

  5. 3D Cloud Radiative Effects on Polarized Reflectances

    Science.gov (United States)

    Cornet, C.; Matar, C.; C-Labonnote, L.; Szczap, F.; Waquet, F.; Parol, F.; Riedi, J.

    2017-12-01

    As recognized in the last IPCC report, clouds have a major importance in the climate budget and need to be better characterized. Remote sensing observations are a way to obtain either global observations of cloud from satellites or a very fine description of clouds from airborne measurements. An increasing numbers of radiometers plan to measure polarized reflectances in addition to total reflectances, since this information is very helpful to obtain aerosol or cloud properties. In a near future, for example, the Multi-viewing, Multi-channel, Multi-polarization Imager (3MI) will be part the EPS-SG Eumetsat-ESA mission. It will achieve multi-angular polarimetric measurements from visible to shortwave infrared wavelengths. An airborne prototype, OSIRIS (Observing System Including Polarization in the Solar Infrared Spectrum), is also presently developed at the Laboratoire d'Optique Atmospherique and had already participated to several measurements campaigns. In order to analyze suitably the measured signal, it it necessary to have realistic and accurate models able to simulate polarized reflectances. The 3DCLOUD model (Szczap et al., 2014) was used to generate three-dimensional synthetic cloud and the 3D radiative transfer model, 3DMCPOL (Cornet et al., 2010) to compute realistic polarized reflectances. From these simulations, we investigate the effects of 3D cloud structures and heterogeneity on the polarized angular signature often used to retrieve cloud or aerosol properties. We show that 3D effects are weak for flat clouds but become quite significant for fractional clouds above ocean. The 3D effects are quite different according to the observation scale. For the airborne scale (few tens of meter), solar illumination effects can lead to polarized cloud reflectance values higher than the saturation limit predicted by the homogeneous cloud assumption. In the cloud gaps, corresponding to shadowed areas of the total reflectances, polarized signal can also be enhanced

  6. A linear CO chemistry parameterization in a chemistry-transport model: evaluation and application to data assimilation

    Directory of Open Access Journals (Sweden)

    M. Claeyman

    2010-07-01

    Full Text Available This paper presents an evaluation of a new linear parameterization valid for the troposphere and the stratosphere, based on a first order approximation of the carbon monoxide (CO continuity equation. This linear scheme (hereinafter noted LINCO has been implemented in the 3-D Chemical Transport Model (CTM MOCAGE (MOdèle de Chimie Atmospherique Grande Echelle. First, a one and a half years of LINCO simulation has been compared to output obtained from a detailed chemical scheme output. The mean differences between both schemes are about ±25 ppbv (part per billion by volume or 15% in the troposphere and ±10 ppbv or 100% in the stratosphere. Second, LINCO has been compared to diverse observations from satellite instruments covering the troposphere (Measurements Of Pollution In The Troposphere: MOPITT and the stratosphere (Microwave Limb Sounder: MLS and also from aircraft (Measurements of ozone and water vapour by Airbus in-service aircraft: MOZAIC programme mostly flying in the upper troposphere and lower stratosphere (UTLS. In the troposphere, the LINCO seasonal variations as well as the vertical and horizontal distributions are quite close to MOPITT CO observations. However, a bias of ~−40 ppbv is observed at 700 Pa between LINCO and MOPITT. In the stratosphere, MLS and LINCO present similar large-scale patterns, except over the poles where the CO concentration is underestimated by the model. In the UTLS, LINCO presents small biases less than 2% compared to independent MOZAIC profiles. Third, we assimilated MOPITT CO using a variational 3D-FGAT (First Guess at Appropriate Time method in conjunction with MOCAGE for a long run of one and a half years. The data assimilation greatly improves the vertical CO distribution in the troposphere from 700 to 350 hPa compared to independent MOZAIC profiles. At 146 hPa, the assimilated CO distribution is also improved compared to MLS observations by reducing the bias up to a factor of 2 in the tropics

  7. Local fall-out and the animal food chain; Retombees locales et chaine alimentaire animale

    Energy Technology Data Exchange (ETDEWEB)

    Prat, G.; Mercier, F.J. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1967-07-01

    The local consequences of fresh fall-out, especially in the case of atmospheric nuclear explosions, are reviewed from the point of view of the internal contamination of the consumer of foodstuffs of animal origin. The edibility of foodstuffs derived from animals having grazed in the presence of fall-out is evaluated both from the wholesome and radio-toxicological points of view. The contamination level of these foodstuffs is calculated as a function of the ground fall-out, and of agronomical and ecological parameters for each radio-nuclide of the animal food chain. The internal exposure of the human consumer is calculated from this level as a function of the diet and of various parameters especially temporal. The equivalent dose to each critical organ, including the digestive tract is deduced from the burdens of each organ. From this a nutritional hygiene in the areas affected by fall-out is obtained, in relationship to the action levels fixed by the responsible authorities in exceptional circumstances. Criteria for these action levels are given as function of the food rations. (authors) [French] Les consequences locales des retombees fraiches, notamment dans le cas d'explosions nucleaires atmospheriques, sont passees en revue en ce qui concerne les problemes de contamination interne du consommateur de denrees d'origine animale. La comestibilite des aliments provenant de betes de boucherie ayant pature sous les retombees est evaluee au double point de vue de la salubrite et de la radiotoxicologie. Le niveau de contamination de ces denrees est calcule en fonction de la retombee au sol, des parametres agronomiques et ecologiques pour chaque radioelement de la chaine alimentaire animale. La contamination interne du consommateur humain est calculee a partir de ce niveau en fonction des modalites d'ingestion et de divers parametres, notamment temporels. L'equivalent de dose au niveau de chaque organe critique, y compris le tube digestif, est deduit

  8. Local fall-out and the animal food chain; Retombees locales et chaine alimentaire animale

    Energy Technology Data Exchange (ETDEWEB)

    Prat, G; Mercier, F J [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1967-07-01

    The local consequences of fresh fall-out, especially in the case of atmospheric nuclear explosions, are reviewed from the point of view of the internal contamination of the consumer of foodstuffs of animal origin. The edibility of foodstuffs derived from animals having grazed in the presence of fall-out is evaluated both from the wholesome and radio-toxicological points of view. The contamination level of these foodstuffs is calculated as a function of the ground fall-out, and of agronomical and ecological parameters for each radio-nuclide of the animal food chain. The internal exposure of the human consumer is calculated from this level as a function of the diet and of various parameters especially temporal. The equivalent dose to each critical organ, including the digestive tract is deduced from the burdens of each organ. From this a nutritional hygiene in the areas affected by fall-out is obtained, in relationship to the action levels fixed by the responsible authorities in exceptional circumstances. Criteria for these action levels are given as function of the food rations. (authors) [French] Les consequences locales des retombees fraiches, notamment dans le cas d'explosions nucleaires atmospheriques, sont passees en revue en ce qui concerne les problemes de contamination interne du consommateur de denrees d'origine animale. La comestibilite des aliments provenant de betes de boucherie ayant pature sous les retombees est evaluee au double point de vue de la salubrite et de la radiotoxicologie. Le niveau de contamination de ces denrees est calcule en fonction de la retombee au sol, des parametres agronomiques et ecologiques pour chaque radioelement de la chaine alimentaire animale. La contamination interne du consommateur humain est calculee a partir de ce niveau en fonction des modalites d'ingestion et de divers parametres, notamment temporels. L'equivalent de dose au niveau de chaque organe critique, y compris le tube digestif, est deduit des charges de ces

  9. OSIRIS reactor radioprotection, radioprotection measurements performed during the power rise and the first 50 megawatt operation; Radioprotection de la pile OSIRIS, mesures de radioprotection effectuees au cours de la montee en puissance et des premiers fonctionnements a 50 megawatts

    Energy Technology Data Exchange (ETDEWEB)

    Fanton, B.; Lebouleux, P

    1967-12-01

    The authors supply the results of the measurements that have been made near the Osiris reactor during the power increase and during the first functioning at 50 megawatts. The measurements relate to the absorbed dose rates in the premises, the water activation and the atmospheric contamination. The influence of the heat layer of water movements and the water rate in the core chimney on the absorbed dose rate at the footbridge level overhanging the pile core has been studied. The modifications to the protection devices that have been proposed after the measurements and the effect of these modifications on the results of the measures are given then. The regeneration process of a water purification chain has been examined from the radiation protection point of view. It has been possible to make some twenty radionuclides obvious in the produced effluents and to determine the volume activity of these effluents for each radionuclide. The whole of results show that in a general way, the irradiation levels are low during the usual reactor functioning. [French] Les auteurs fournissent les resultats des mesures de radioprotection oui ont ete effectuees aupres de la pile Osiris pendant la montee en puissance et au cours des premiers fonctionnements a 50 megawatts. Les mesures portent sur les debits de dose absorbee dans les locaux, l'activation de l'eau et la contamination atmospherique. L'influence de la couche chaude des mouvements d'eau et du debit d'eau dans la cheminee du coeur sur le debit de dose absorbee au niveau de la passerelle surplombant le coeur de la pile, a ete etudiee. Les modifications aux dispositifs de protection, qui ont ete proposees a la suite des mesures, et l'effet de ces modifications sur les resultats des mesures sont indiques ensuite. Le processus de regeneration d'une chaine d'epuration de l'eau a ete examine sous l'angle de la radioprotection. Il a ete possible de mettre en evidence une vingtaine

  10. Starting up a programme of atomic piles using compressed gas; Le demarrage d'un programme de piles atomiques a gaz comprime

    Energy Technology Data Exchange (ETDEWEB)

    Horowitz, J; Yvon, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1959-07-01

    1) An examination of the intellectual and material resources which have directed the French programme towards: a) the natural uranium and plutonium system, b) the use of compressed gas as heat transfer fluid (primary fluid). 2) The parts played in exploring the field by the pile EL2 and G1, EL2 a natural uranium, heavy water and compressed gas pile, G1 a natural uranium, graphite and atmospheric air pile. 3) Development of the neutronics of graphite piles: physical study of G1. 4) The examination of certain problem posed by centres equipped with natural uranium, graphite and compressed carbon dioxide piles: structure, special materials, fluid circuits, maximum efficiency. Economic aspects. 5) Aids to progress: a) piles for testing materials and for tests on canned fuel elements, b) laboratory and calculation facilities. 6) Possible new orientations of compressed gas piles: a) raising of the pressure, b) enriched fuel, c) higher temperatures, d) use of heavy water. (author) [French] 1) Examen des ressources - intellectuelles et materielles - qui ont oriente le programme fran is vers: a) la voie de l'uranium naturel et du plutonium; b) l'emploi comme fluide pour le transfert de la chaleur (fluide primaire) d'un gaz comprime. 2) Le role d'exploration des piles EL2 et G1, EL2 pile a uranium naturel, eau lourde et gaz comprime, G1 pile a uranium naturel, graphite et air atmospherique. 3) Developpement de la neutronique des piles a graphite: l'etude physique de G1. 4) Examen de certains problemes poses par les centrales equipees de piles a uranium naturel, graphite et gaz carbonique comprime: structure, materiaux speciaux, circuits de fluides, optimisation. Aspects economiques. 5) Les auxiliaires du progres: a) piles pour essai de materiaux et pour essais de cartouches, b) moyens de laboratoire et moyens de calcul. 6) Orientations nouvelles possibles des piles a gaz comprime: a) elevation de la pression, b) combustible enrichi, c) temperatures elevees, d) emploi de l

  11. Airborne lidar measurements of aerosol spatial distribution and optical properties over the Atlantic Ocean during a European pollution outbreak of ACE-2[Special issue with manuscripts related to the second Aerosol Characterization Experiment (ACE-2), 16 June-25 July 1997

    Energy Technology Data Exchange (ETDEWEB)

    Flamant, Cyrille; Pelon, Jaques; Trouillet, Vincent; Bruneau, Didier [CNRS-UPMC-UVSQ, Paris (France). Service d' Aeronomie; Chazette, Patrick; Leon, J.F. [CEA-CNRS, Gif-sur-Yvette (France). Lab. des Sciences du Climat et de l' Environment; Quinn, P.K.; Bates, T.S.; Johnson, James [National Oceanic and Atmospheric Administration, Seattle, WA (United States). Pacific Marine Environmental Lab.; Frouin, Robert [Scripps Inst. of Oceanography, La Jolla, CA (United States); Livingston, John [SRI International, Menlo Park, CA (United States)

    2000-04-01

    Airborne lidar measurements of the aerosol spatial distribution and optical properties associated with an European pollution outbreak which occurred during the Second Aerosol Characterization Experiment (ACE-2) are presented. Size distribution spectra measured over the ocean near Sagres (Portugal), on-board the Research Vessel Vodyanitsky and on-board the Avion de Recherche Atmospherique et Teledetection (ARAT) have been used to parameterize the aerosol vertical distribution. This parameterization, which is essential to the analysis of airborne lidar measurements, has been validated via closure experiments on extinction coefficient profiles and aerosol optical depth (AOD). During the studied event, AOD's retrieved from lidar measurements at 0.73 {mu}m range between 0.055 and 0.10. The parameterized aerosol vertical distribution has been used to shift AOD retrievals from 0.73 to 0.55 {mu}m to enable comparison with other remote sensing instruments. At the latter wavelength, AOD's retrieved from lidar measurements range between 0.08 and 0.14. An agreement better than 20% is obtained between AOD's derived from lidar and sunphotometer measurements made at the same time and place over the ocean near the coast. However, large differences are observed with the AOD estimated from Meteosat imagery in the same area. These differences are thought to be caused by large uncertainties associated with the Meteosat sensitivity for small AOD's or by the presence of thin scattered clouds. Lidar-derived particulate extinction profiles and scattering coefficient profiles measured by a nephelometer mounted on the ARAT, in a different part of the plume, were found in good agreement, which could be an indication that absorption by pollution aerosols is small and/or that soot is present in small amounts in the European pollution plume. Lidar measurements have also been used to differentiate the contribution of different aerosol layers to the total AOD. It is shown that

  12. Decontamination of material in the Marcoule plutonium producing centre (1961); La decontamination du materiel dans le centre de production du plutonium de Marcoule (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Rodier, J; Bouzigues, H; Boutot, P [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

    1961-07-01

    adoptee. Le travail s'effectue en cuves, le dosage precis des bains etant realise a partir d'un pupitre de commande. L'experience de fonctionnement a montre qu'en raison du travail en milieu humide les problemes de contamination atmospherique ne se posent pas: de ce fait, les agents peuvent travailler sans dispositifs de protection speciaux. Pratiquement tout materiel peut etre recupere et les operations n'entrainent qu'un assez faible volume d'effluents. Le fonctionnement de l'atelier est assure par un petit nombre d'agents. Les frais d'exploitation, y compris amortissement et traitement des effluents, ne depassent pas 15 pour cent de la valeur marchande des pieces traitees. (auteurs)

  13. Detection of tritium in the CO{sub 2} of the reactors G2/G3 using gas chromatography; La detection du tritium par chromatographie gazeuse dans le CO{sub 2} des piles G2/G3

    Energy Technology Data Exchange (ETDEWEB)

    Guillermin, P; Rossi, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    This gas-phase chromatographic method, based on the principle of the decomposition of a gas mixture into its pure constituents, makes it possible to identify and rapidly measure the tritium present in the heat-carrying fluid of the reactors G2/G3. The sensitivity limit corresponds to 5 x 10{sup -6} {mu}Ci/cm{sup 3} of tritiated gas, whereas the threshold reading of the D.C.C.A. is 10{sup -3} {mu}Ci/cm{sup 3} in the presence of {sup 41}A. This apparatus has interesting applications in the conditions where certain {beta} emitters (products of fission or of activation) interfere with the measurement of the tritium. It can easily be adapted to the detection of tritiated steam on condition that a reducing chemical treatment is applied for the atmospheric humidity. In fact, although this method is not as sensitive for the measurement of tritiated vapour as p-spectrometry in a scintillating medium, it may be set up very easily for measuring the C.M.A of tritium in air and is not affected by the presence of radio-active gases. (authors) [French] Cette methode de chromatographie en phase gazeuse, basee sur le principe de decomposition d'un melange gazeux en ses constituants purs, permet l'identification et la mesure rapide du tritium present dans le fluide caloporteur des piles G2/G3. La limite de sensibilite correspond a 5.10{sup -6} {mu}Ci/cm{sup 3} de gaz tritie, alors que le seuil de lecture du D.C.C.A. s'eleve a 10{sup -3} {mu}Ci/cm{sup 3} en presence de {sup 41}A. Cet appareillage presente un champ d'application interessant dans les domaines ou certains emetteurs {beta} (produits de fission ou d'activation) genent la mesure du tritium. Il peut s'adapter sans difficulte a la detection de la vapeur tritiee moyennant un traitement chimique reducteur de l'humidite atmospherique. En definitive, bien que cette methode ne soit pas aussi sensible pour la determination de la vapeur tritiee que la spectrometrie {beta} en milieu scintillant, elle permet de mesurer la C.M.A de

  14. Design and study of the performance of a Raman lidar model, combining a pulsed laser source and a holographic grating double monochromator; Realisation et etudes des performances d'une maquette de lidar Raman combinant une source laser impulsionnelle et un double monochromateur a reseaux holographiques

    Energy Technology Data Exchange (ETDEWEB)

    Nacass, Philippe

    1976-03-16

    The various techniques for the analysis of air constituents are studied briefly to help design an apparatus for detecting, localizing, identifying and measuring atmospheric pollution. The optical methods known under the name of Lidar (Light direction and ranging) appear to give good qualitative and quantitative results since they do not involve any sampling of the observed medium. Amongst these methods, the Raman laser back-scattering in which the characteristic frequency of a molecule can be isolated from those of the other constituents of air is studied in more details. The design and realization, based on the conclusions of this study, and the measurements of the performance of a Raman Lidar preliminary model are then described. Its originality lies in the use of holographic grating monochromators and the overall simplicity of operation of the system. Using this system, it was possible to make in-situ Raman back-scattering measurements on N{sub 2}, O{sub 2}, H{sub 2}O in the atmosphere and on large concentrations of CO{sub 2} at distances between 30 and 40 m, which give a reasonable estimate of the sensitivity and of the range of a full scale, more performing final design. (author) [French] En vue de la realisation d'un dispositif permettant la detection, la localisation, l'identification et le dosage a distance de la pollution atmospherique, les differentes techniques d'analyse des constituants de l'air sont etudiees rapidement. Les methodes optiques appelees Lidar (Light Detection And Ranging) paraissent les plus adaptees pour des mesures qualitatives et quantitatives, car elles ne necessitent pas de prelevement du milieu observe. Parmi ces methodes, la retrodiffusion Raman Laser, qui permet d'isoler la frequence propre caracteristique d'une molecule sans interference avec les autres constituants de l'air est etudiee plus en details. La realisation, basee sur les conclusions de cette etude, puis la mesure des performances d'une maquette preliminaire de Lidar

  15. In situ airborne measurements of aerosol optical properties during photochemical pollution events

    Science.gov (United States)

    Mallet, M.; van Dingenen, R.; Roger, J. C.; Despiau, S.; Cachier, H.

    2005-02-01

    Dry aerosol optical properties (scattering, absorbing coefficients, and single scattering albedo) were derived from in situ airborne measurements during two photochemical pollution events (25 and 26 June) observed during the Experience sur Site pour Contraindre les Modeles de Pollution atmospherique et de Transport d'Emissions (ESCOMPTE) experiment. Two flights were carried out during daytime (one during the morning and one at noon) over a domain, allowing the investigation of how an air pollution event affects the particle optical properties. Both horizontal distribution and vertical profiles are presented. Results from the horizontal mapping show that plumes of enhanced scattering and absorption are formed in the planetary boundary layer (PBL) during the day in the sea breeze-driven outflow of the coastal urban-industrial area of Marseille-Fos de Berre. The domain-averaged scattering coefficient (at 550 nm) over land σs changes from 35 (28) Mm-1 during land breeze to 63 (43) Mm-1 during sea breeze on 25 June (26 June), with local maxima reaching > 100 Mm-1. The increase in the scattering coefficient is associated with new particle formation, indicative of secondary aerosol formation. Simultaneously, the domain-averaged absorption coefficient increases from 5.6 (3.4) Mm-1 to 9.3 (8.0) Mm-1. The pollution plume leads to strong gradients in the single scattering albedo ωo over the domain studied, with local values as low as 0.73 observed inside the pollution plume. The role of photochemistry and secondary aerosol formation during the 25 June case is shown to increase ωo and to make the aerosol more `reflecting' while the plume moves away from the sources. The lower photochemical activity, observed in the 26 June case, induces a relatively higher contribution of black carbon, making the aerosol more absorbing. Results from vertical profiles at a single near-urban location in the domain indicate that the changes in optical properties happen almost entirely within

  16. Vertical velocity and turbulence aspects during Mistral events as observed by UHF wind profilers

    Energy Technology Data Exchange (ETDEWEB)

    Caccia, J.L.; Guenard, V. [LSEET, CNRS/Univ. de Toulon, La Garde (France); Benech, B.; Campistron, B. [CRA/LA, CNRS/Obs. Midi-Pyrenees, Campistrous (France); Drobinski, P. [IPSL/SA, CNRS/Univ. de Paris VI, Paris (France)

    2004-07-01

    The general purpose of this paper is to experimentally study mesoscale dynamical aspects of the Mistral in the coastal area located at the exit of the Rhone-valley. The Mistral is a northerly low-level flow blowing in southern France along the Rhone-valley axis, located between the French Alps and the Massif Central, towards the Mediterranean Sea. The experimental data are obtained by UHF wind profilers deployed during two major field campaigns, MAP (mesoscale alpine program) in autumn 1999, and ESCOMPTE (Experience sur Site pour COntraindre les Modeles de Pollution atmospheriques et de Transports d'Emission) in summer 2001. Thanks to the use of the time evolution of the vertical profile of the horizontal wind vector, recent works have shown that the dynamics of the Mistral is highly dependent on the season because of the occurrence of specific synoptic patterns. In addition, during summer, thermal forcing leads to a combination of sea breeze with Mistral and weaker Mistral due to the enhanced friction while, during autumn, absence of convective turbulence leads to substantial acceleration as low-level jets are generated in the stably stratified planetary boundary layer. At the exit of the Rhone valley, the gap flow dynamics dominates, whereas at the lee of the Alps, the dynamics is driven by the relative contribution of ''flow around'' and ''flow over'' mechanisms, upstream of the Alps. This paper analyses vertical velocity and turbulence, i.e. turbulent dissipation rate, with data obtained by the same UHF wind profilers during the same Mistral events. In autumn, the motions are found to be globally and significantly subsident, which is coherent for a dry, cold and stable flow approaching the sea, and the turbulence is found to be of pure dynamical origin (wind shears and mountain/lee wave breaking), which is coherent with non-convective situations. In summer, due to the ground heating and to the interactions with

  17. OSIRIS reactor radioprotection, radioprotection measurements performed during the power rise and the first 50 megawatt operation; Radioprotection de la pile OSIRIS, mesures de radioprotection effectuees au cours de la montee en puissance et des premiers fonctionnements a 50 megawatts

    Energy Technology Data Exchange (ETDEWEB)

    Fanton, B; Lebouleux, P

    1967-12-01

    The authors supply the results of the measurements that have been made near the Osiris reactor during the power increase and during the first functioning at 50 megawatts. The measurements relate to the absorbed dose rates in the premises, the water activation and the atmospheric contamination. The influence of the heat layer of water movements and the water rate in the core chimney on the absorbed dose rate at the footbridge level overhanging the pile core has been studied. The modifications to the protection devices that have been proposed after the measurements and the effect of these modifications on the results of the measures are given then. The regeneration process of a water purification chain has been examined from the radiation protection point of view. It has been possible to make some twenty radionuclides obvious in the produced effluents and to determine the volume activity of these effluents for each radionuclide. The whole of results show that in a general way, the irradiation levels are low during the usual reactor functioning. [French] Les auteurs fournissent les resultats des mesures de radioprotection oui ont ete effectuees aupres de la pile Osiris pendant la montee en puissance et au cours des premiers fonctionnements a 50 megawatts. Les mesures portent sur les debits de dose absorbee dans les locaux, l'activation de l'eau et la contamination atmospherique. L'influence de la couche chaude des mouvements d'eau et du debit d'eau dans la cheminee du coeur sur le debit de dose absorbee au niveau de la passerelle surplombant le coeur de la pile, a ete etudiee. Les modifications aux dispositifs de protection, qui ont ete proposees a la suite des mesures, et l'effet de ces modifications sur les resultats des mesures sont indiques ensuite. Le processus de regeneration d'une chaine d'epuration de l'eau a ete examine sous l'angle de la radioprotection. Il a ete possible de mettre en evidence une vingtaine de radionucleides dans les effluents produits et de

  18. Analysis of the sources and dynamic processes leading to the increase of atmospheric CO2, black carbon and other trace species during recent urban pollution events in the Paris megacity region : a synergy of resources provided by the IPSL OCAPI platform.

    Science.gov (United States)

    Xueref-Remy, I.; Foret, G.; Beekmann, M.; Brégonzio-Rozier, L.; Favez, O.; Gros, V.; Moreau-Guigon, E.; Vogel, F. R.; Belviso, S.; Ghersi, V.; Dupont, J. C.; Bodichon, R.; Cailteau-Fischbach, C.; Baisnee, D.; Peinado, F.; Haeffelin, M.; DeCola, P.; Turnbull, J. C.; Chelin, P.; Te, Y. V.; Formenti, P.; Doussin, J. F.; Gratien, A.; Desboeufs, K. V.; Ramage, K.; Jeseck, P.; Delmotte, M.; Ramonet, M.; Michoud, V.; Ravetta, F.

    2016-12-01

    Nowadays, more than 50% of the global population leave in urban centers which activities generate large anthropogenic emissions of CO2 (more than 70% of fossil fuel CO2 comes from urbanized/industrialized areas) and reactive gases that endanger our climate, the health of human beings and surrounding ecosystems. The worst situations are encountered during urban pollution events that usually form under anticyclonic conditions. Analyzing the contribution of the local and regional sources of urban CO2 and co-emitted species vs the remote ones, as well as the nature of these sources and the dynamical processes that lead to the building of such events can provide interesting knowledge for helping urban policy makers to better identify the role of anthropogenic/biogenic sources on the urban air composition and to take proper decisions in matter of CO2 and pollutants sources mitigation. With 12 million of people, Paris (France) is the second megacity in Europe. In 2016, two pollution events occured in the Paris region during which the instrumental platform OCAPI (http://observations.ipsl.fr/composition-atmospherique-en-idf.html) from IPSL (Institut Pierre Simon Laplace) was mobilized in collaboration with air quality governing actors (AIRPARIF, INERIS) to collect a bunch of observations. Five sites located in the urban, peri-urban and rural areas of Paris were equiped with in-situ analyzers (CO2, CO, black carbon, 13CO2, COS) ; Fourier transform spectrometers for column measurements (XCO2, XCO, XCOS), particle filters (for aerosols size and content analysis) ; air samples (levoglucosan, 14CO2, VOCs) ; and Lidar profilers (boundary layer height ; wind profiles). These data, combined with a backtrajectories analysis, give information about the dynamical processes that lead to the formation of the pollution events and on the contribution of local, regional and remote sources. The analysis of the correlations between the trace species and of the isotopic content of carbon in

  19. The Radioisotopic Determination of Diffusion Coefficients and Currents in Natural Waters. Surface Collection of Radioactive Fall-Out on a Large Alpine Lake; Determination par detection nucleaire des coefficients de diffusion et des courants dans les eaux naturelles. Evolution de la surface de collection d'un grand lac alpin pour les retombees radioactives; Opredelenie koehffitsienta diffuzii i skorosti techeniya estestvennykh vod pri pomoshchi yadernogo detektirovaniya. Ehvolyutsiya poverkhnosti sbora radioaktivnykh osadkov na bol'shom al'pijskom ozere; Determinacion por deteccion nuclear de los coeficientes de difusion y de las corrientes en las aguas naturales evolucion de la superficie de captacion de un gran lago alpino para las precipitaciones radiactivas

    Energy Technology Data Exchange (ETDEWEB)

    Chesselet, R.; Nordemann, D. [Service d' Electronique Physique, Centre d' Etudes Nucleaires de Saclay (France); Dussart, B. [Centre de Recherches Hydrobiologiques, CNRS, Gif-sur-Yvette (France)

    1963-08-15

    'un coefficient de diffusion pour l'emetteur utilise et a la mesure eventuelle de la vitesse du courant au point ou la mesure est effectuee (dans le cas decrit, le lac Leman). Dans une seconde etape, en correlation avec une etude de geophysique concernant le probleme general des retombees radioactives, les auteurs ont utilise l'apport des retombees radioactives ayant pour origine les essais nucleaires atmospheriques (octobre 1961-janvier 1962). Des mesures de la radioactivite ont ete effectuees chaque jour sur des prelevements d'eau du lac Leman a des profondeurs de 0 m, 10 m, 20 m et sur un collecteur de retombees atmospheriques seches et humides. Malgre la complexite du regime des apports en fonction du temps, l'interpretation des diagrammes obtenus peut contribuer a resoudre le probleme du devenir des produits radioactifs dans les conditions de diffusion et de courants rencontrees. L'utilisation de la diffusion de produits radioactifs en tres faibles quantites et des differentes techniques de detection nucleaires a haute sensibilite actuellement disponibles peut conduire a une meilleure connaissance de la diffusion in situ et du mouvement des masses d'eaux naturelles. (author) [Spanish] En una primera etapa, los autores ha i provecado la difusion in situ de un emisor radiactivo, el sodio-22 en forma de Na{sup +}, de actividad muy baja (inferior al milicurie). La aplicacion de las leyes de la difusion a este caso facilita el calculo de la velocidad de difusion de la ''nube radiactiva''. Por consiguiente, el registro en funcion del tiempo de las actividades medidas con dos detectores gamma dispuestos de modo conveniente permite asignar un coeficiente de difusion ai emisor empleado y, eventualmente, evaluar la velocidad de la corriente en el punto en que se efectua la medicion (en el caso descrito, el lago Leman). En una segunda etapa, en relacion con un estudio geofisico del problema general de las precipitaciones radiactivas, los autores utilizaron la aportacion de las

  20. Caracterización química de la vidriera del rosetón del Duomo de Siena (Italia, 1288-1289

    Directory of Open Access Journals (Sweden)

    Tarozzi, C.

    2010-06-01

    with addition of copper (together with manganese and iron, previously prepared as a pigment that has as excipient a potassium glass. The use of potassium glass instead of the sodium glass locally produced strongly suggests that the pigment could be bought directly from Middle or Northern Europe markets and/or could be a sub-product of copper ore melting. On the other hand, the production of sodium red ruby plaqué glass, technologically more evolved and comparable to the coeval potassium glass coming from the Central Europe glass factories, would be outstanding in the XIV century; but we interpret (taking into account its chemical composition that was produced later and introduced during the restoration conducted at the end of XVII century. We can also note the use of well-dosed lead additions in order to increase the lightness and transparency of coloured glass. Manganese has been a very important element in the Siena workshop glassmaker colour palette achievements. On the other hand, the trace-element chemical fingerprint of the glass allows arguing what kind of mineral salts were used as pigments, as well as the way to introduce it in the uncoloured original glass.

    Se han caracterizado químicamente una colección de vidrios arquitectónicos coloreados originales del rosetón del Duomo (catedral de Siena, Italia, realizados bajo diseño del artista Duccio di Buoninsegna en 1288-89. Esta comunicación expone los resultados obtenidos mediante el empleo de microsonda electrónica de Castaing (mayoritarios y espectrometría de masas con fuente de plasma acoplado inductivamente (ICP-MS, elementos en traza en vidrios de varios colores (incoloro, verde oscuro, verde oliva, amarillo, violeta, rosa, azul oscuro, azul celeste, rojo plaqué. Se trata de vidrios sódico-cálcicos (valores en peso alrededor del 13-14 % de Na2O, 56-64 % SiO2, 4% MgO, 9-10 % CaO, 2,5-4 K2O de tradición por tanto mediterránea. Un resultado semejante

  1. Freinet en España (1926-1939 - Freinet in Spain (1926-1939

    Directory of Open Access Journals (Sweden)

    José Luis Hernández Huerta

    2012-03-01

    Full Text Available Freinet na Espanha (1926-1939ResumoOs postulados sobre educação de Celestín Freinet, em seu empenho de dotar a Cooperativa de Ensino Laico - CEL - de um caráter internacional, transcendem as fronteiras francesas. A Espanha não ficou alheia a essa influência e logo a sua proposta foi bem acolhida apesar de, num primeiro momento, ter tido uma difusão escassa e pouca aplicação. Foram os ventos da renovação pedagógica propiciados pela Segunda República que deram o impulso e fomentaram a prática das novas técnicas educativas provenientes da França. Assim, o incipiente movimento freinetiano espanhol foi tomando corpo e, em pouco tempo, contou com um batalhão de mestres franco atiradores, uma sólida organização e um futuro promissor, marcado pelo começo da guerra civil. Esta pesquisa investiga a recepção espanhola da Escola Moderna, a divulgação e difusão da mesma, o itinerário seguido pelo movimento freinetiano espanhol em sua expansão e depuração franquista. Também apresenta um esboço do perfil dos professores integrantes do movimento.Palavras-chave: Freinet; Espanha; II República; depuração; renovação pedagó-gica; escola moderna.  FREINET IN SPAIN (1926-1939AbstractThe postulates on education from Celestín Freinet, and his determination to provide to the Cooperative of Lay Education - CLE - of an international character, came out soon the French borders. Spain was not foreign to such influence and, very soon, the Freinet’s educational offer had a good reception, even though, in the first moment, it had scanty diffusion and minor application. The winds of pedagogic renovation, propitiated by the Spanish Second Republic, gave impulse and encouraged the application of the new educational technologies from France. Thus, the incipient freinet’s spanish movement was taking shape and, in a little time, this had a battalion of sniper teachers, who wanted to apply those ideas, a solid organization and a promising

  2. Study of gamma radiation between 0.1 and 1.0 MeV in the earth's atmosphere; Etude du rayonnement gamma entre 0,1 et 1 Mev dans l'atmosphere terrestre

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-01-01

    celestes, la lune en particulier. Nous abordons cette etude dans les 2e et 3e parties de cet expose. (auteur)

  3. A proof of the cancellation of the redistribution tidal potential effects on the rotation of an elastic Earth model

    Science.gov (United States)

    Baenas, Tomás; Escapa, Alberto; Ferrándiz, Jose Manuel

    2014-05-01

    2010-22039-C02-02, and Universidad de Alicante project GRE11-08. Escapa, A., Getino, J., & Ferrándiz, J. M. 2004, Proc. Journées Sys. Ref., Ed. N. Capitaine, Paris, 70 Ferrándiz, J. M., Baenas, T., & Escapa, A. 2012, Geophys. Res. Abs., 14, EGU2012-6175 Krasinsky, G. A. 1999, Celest. Mech. Dyn. Astron., 75, 39 Lambert, S. & Mathews, P. M. 2006, A&A, 453, 363

  4. Determinantes sociales de salud en los agricultores del resguardo indígena Zenú

    Directory of Open Access Journals (Sweden)

    Elsy C. Puello A.

    2016-04-01

    Full Text Available Objetivo: Analizar los determinantes sociales de salud presentes entre los indígenas agricultores del Resguardo Zenú de San Andrés de Sotavento. Metodología: Estudio descriptivo de corte, con enfoque cuantitativo, participaron 64 indígenas agricultores de las comunidades Celeste Imperio y Santa Elena del Municipio de San Andrés de Sotavento en el año 2012, se seleccionaron bajo la técnica del muestreo aleatorio simple. La recolección de la información se efectuó a través de encuestas estructuradas diligenciadas mediante entrevista. Resultados: El rango de edad de la población sujeto osciló entre 18 a 70 años, existe 41% de analfabetismo absoluto, las familias son extensas con orientación endogámica, las condiciones de vida son precarias, hay ausencia de actividad recreativa y actividad física programada, 97% percibe menos de un salario mínimo mensual legal vigente producto del trabajo comunitario, 95.3% pertenece al regimen de salud subsidiado, todos carecen de afiliación a riesgos laborales y pensión, 77% admitió que tuvo algún accidente laboral en el último año, así mismo, 70% manifestó morbilidad sentida relacionada con la actividad laboral. Conclusiones: Los determinantes de carácter social que influyen negativamente en la salud identificados fueron: sociopolítico, circunstancias materiales, factores biológicos, conductuales y laborales; los cuales se reflejan en deficiencias en su calidad de vida, morbilidad sentida, accidentalidad laboral, fragilidades en el Sistema de Protección Social, altos índices de analfabetismo absoluto, pobreza y características que indiscutiblemente reafirman la relación perversa e interdependiente entre analfabetismo, pobreza y salud. Sin embargo, la cohesión social se identificó como determinante social de influencia positiva para la salud (94%.

  5. El capítulo sobre el Tasyīr en al-Bāriʻ de Ibn Abī-l-Riŷāl y su traducción alfonsí

    Directory of Open Access Journals (Sweden)

    Díaz-Fajardo, Montse

    2011-12-01

    Full Text Available Tasyīr or “prorogation”, is an astrological procedure with which the astrologer moves, in an imaginary way, an indicator in order to determine the celestial influences. Tasyīr was one of the astrologer’s fundamental tools for the casting of a horoscope. This paper analyzes the information in the chapter on Tasyīr in Ibn Abī l-Rijāl’s (11th century book al-Bāri‘, concerning the methods, the techniques and the resources used. Its study highlights the channels through which science was transmitted and the ways in which the astrologer wrote his work using other sources, and stresses the importance of al-Bāri‘ in introducing new astrological knowledge from the East into the Maghrib and medieval Europe (knowledge that was used until the fifteenth century. The comparison of the chapter with its Castilian translation provides evidence of the procedures used by the translators of Alfonso X.El tasyīr o «prorrogación» es un procedimiento astrológico por el que se hace avanzar de forma imaginaria un indicador para conocer las influencias celestes. El tasyīr fue una de las herramientas fundamentales del astrólogo en el levantamiento de un horóscopo. Este artículo analiza la información que contiene el capítulo “Sobre el tasyīr” de la obra al-Bāri‘ de Ibn Abī-l-Riŷāl (siglo XI: los métodos, las técnicas y los recursos que utilizaba. Su estudio nos muestra las vías por las que la ciencia se transmitía, el modo en el que el astrólogo elaboraba su obra, la importancia del al-Bāri‘ como introductor en el Magreb y en la Europa medieval de fuentes y conocimientos nuevos importados de Oriente y la vigencia de su astrología hasta el siglo XV. El cotejo del capítulo mencionado con su traducción castellana nos da pruebas de la forma de trabajar de los traductores de Alfonso X.

  6. Estrategias de presentación de espárragos (Asparagus officinalis L.: preferencias de los consumidores

    Directory of Open Access Journals (Sweden)

    Ana M. Castagnino

    2011-06-01

    Full Text Available Los espárragos constituyen un producto hortícola no tradicional altamente perecedero que requiere ser comercializado con una adecuada presentación que permita prolongar su vida útil y al mismo tiempo brindar información sobre el producto como un servicio al consumidor que estimule el consumo. Dentro de las posibilidades de presentación se encuentran los tradicionales atados y actualmente, a nivel global, se está difundiendo el empleo de bandejas que permite una presentación IV Gama del producto final. La IV Gama representa un modelo de producción idóneo para elevar el nivel de servicio de los productos hortícolas frescos en general, lograr una mayor exhibición y la expansión del consumo. Con la finalidad de conocer las preferencias de los consumidores de espárrago respecto de los distintos atributos del producto final, se efectuó un estudio de diez variables: 1 tipos de envases (bandeja: B, atados con y sin film: ACR y ASR; 2 presencia de etiquetas (E; 3 color: en etiquetas (CE; 4 de fondo (CF; 5 de letras (CL; 6 presencia: de recetario (R; 7 de indicaciones de valor nutricional (VN; 8 de ilustraciones (I; 9 de logos (Lg y 10 calibres: G: grande; M: mediano y P: pequeño; asignando a cada una un puntaje de 1 – 10. A tal fin se efectuó un panel test a treinta y cuatro potenciales consumidores el 13/11/2008. Los CF utilizados fueron: 1: verde, 2: amarillo, 3: anaranjado, 4: celeste. Se encontraron diferencias. ACR obtuvo 47 % (puntaje 10, E fue muy valorado (70 % el mayor valor, 85 % consideró importante la presencia de color en las etiquetas, siendo el anaranjado con 53 % el color preferido de fondo, seguido del amarillo (32 % y para las letras el color negro (88 %. R y Lg fue muy valorado por el 90 %, mientras que VN e I por el 80 %. El 61 % de los consumidores prefirió el calibre M.

  7. Study of gamma radiation between 0.1 and 1.0 MeV in the earth's atmosphere; Etude du rayonnement gamma entre 0,1 et 1 Mev dans l'atmosphere terrestre

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-01-01

    secondaire emis par le meme processus pour les autres corps celestes, la lune en particulier. Nous abordons cette etude dans les 2e et 3e parties de cet expose. (auteur)

  8. LA TÉCNICA EN LA ECONOMÍA Y LA INVESTIGACIÓN

    Directory of Open Access Journals (Sweden)

    Juan Alberto Huaylupo Alcázar

    2011-09-01

    Full Text Available La metodología ha sido una temática manejada y aplicada generalmente por técnicos que se arro-gaban o se les atribuía autoridad para determinar lo que era correcto o indebido en los procesos investigativos y de evaluación de las acciones en el medio social. En el presente se comienza a cuestionar de manera sistemática y cada vez en mayor medida la importancia otorgada a las metodologías o técnicas que se emplean en la investigación y en la evaluación. Esta vertiente crítica, no se puede decir, en sentido estricto, que es totalmente nueva, por el contrario es la continuidad de perspectivas que ya se habían planteado en el pasado.Lo nuevo son las circunstancias que promueven que esos cuestionamientos se aprecien como evidentes y pertinentes en el actual desarrollo científico. La revaloración de posiciones ha implicado también relativos cambios en la concepción de la ciencia y la labor científica, así como también en las aplicaciones de la producción tecnológica. De una idea que suponía que la ciencia proporcionaba los conocimientos absolutos de la realidad y nos daba las fórmulas y recetas de cómo hacer las cosas para obtener determinado resultado, se ha pasado a postular que los conocimientos científicos son relativos, no absolutos, inmutables ni universales. Relatividad fundada en que los conocimientos científicos son históricos, esto es, condicionados por los conocimientos, prejuicios y necesidades sociales existentes en un momento determinado a los que el investigador no se puede abstraer y por lo tanto presentes en sus descubrimientos.Esta modificación ha implicado también una transformación en la concepción de la realidad, de una visión cotidiana de la existencia de leyes universales aplicables a los cuerpos celestes y la sociedad, se ha pasado a postular que las pretendidas leyes, también deberán ser cuestionadas, dado que no existen en el mundo de lo real fenómenos que puedan ser idénticos a otros. La

  9. Como os Alunos do Ensino Médio da Rede Estadual de São Paulo obtém Conhecimentos Astronômicos?

    Science.gov (United States)

    da Cunha, W. S.; Voelzke, M. R.; Amaral, L. H.

    2005-08-01

    Atualmente vivencia-se um mundo globalizado onde os computadores e a internet permitiram um acesso rápido e seguro a todo tipo de informação e conhecimento. O presente trabalho visa analisar a maneira pela qual alunos de segundo grau da rede estadual da cidade de São Paulo obtiveram, caso tenham, conhecimentos básicos de astronomia quanto aos fenômenos celestes que os rodeiam, tais como a sucessão dos dias e das estações do ano, além de questioná~los sobre fatos genéricos tais como: o que vem a ser o Sol, o Big Bang, o que ocasionou a extinção dos dinossauros. Para tanto foi elaborado um formulário constando de questões de múltipla escolha, o qual foi aplicado no primeiro colegial diurno da Escola Estadual Guilherme de Almeida. Num espaço amostral de 44 alunos constatou-se que 41% dos alunos adquiriram seus conhecimentos astronômicos na escola e 59% através da mídia em geral. Neste mesmo espaço amostral apenas 11% dos alunos usaram computadores na escola, 41% na residência, 5% no trabalho e 43% não utilizaram. O presente estudo revelou também que para 50% dos alunos o professor jamais utilizou um programa de computador a respeito de astronomia ou fez alguma apresentação sobre o tema. Embora em sua fase inicial este estudo revela claramente que a maioria dos alunos não obtém na escola seus conhecimentos astronômicos, estes provém de fontes não especificamente didático-pedagógicas tais como filmes e revistas populares que não raramente geram conhecimentos incompletos e em muitos casos inclusive falhos.

  10. Estrategias de presentación de espárragos (Asparagus officinalis L.: preferencias de los consumidores

    Directory of Open Access Journals (Sweden)

    Ana M. Castagnino

    2011-01-01

    Full Text Available Los espárragos constituyen un producto hortícola no tradicional altamente perecedero que requiere ser comercializado con una adecuada presentación que permita prolongar su vida útil y al mismo tiempo brindar información sobre el producto como un servicio al consumidor que estimule el consumo. Dentro de las posibilidades de presentación se encuentran los tradicionales atados y actualmente, a nivel global, se está difundiendo el empleo de bandejas que permite una presentación IV Gama del producto final. La IV Gama representa un modelo de producción idóneo para elevar el nivel de servicio de los productos hortícolas frescos en general, lograr una mayor exhibición y la expansión del consumo. Con la finalidad de conocer las preferencias de los consumidores de espárrago respecto de los distintos atributos del producto final, se efectuó un estudio de diez variables: 1 tipos de envases (bandeja: B, atados con y sin film: ACR y ASR; 2 presencia de etiquetas (E; 3 color: en etiquetas (CE; 4 de fondo (CF; 5 de letras (CL; 6 presencia: de recetario (R; 7 de indicaciones de valor nutricional (VN; 8 de ilustraciones (I; 9 de logos (Lg y 10 calibres: G: grande; M: mediano y P: pequeño; asignando a cada una un puntaje de 1 – 10. A tal fin se efectuó un panel test a treinta y cuatro potenciales consumidores el 13/11/2008. Los CF utilizados fueron: 1: verde, 2: amarillo, 3: anaranjado, 4: celeste. Se encontraron diferencias. ACR obtuvo 47 % (puntaje 10, E fue muy valorado (70 % el mayor valor, 85 % consideró importante la presencia de color en las etiquetas, siendo el anaranjado con 53 % el color preferido de fondo, seguido del amarillo (32 % y para las letras el color negro (88 %. R y Lg fue muy valorado por el 90 %, mientras que VN e I por el 80 %. El 61 % de los consumidores prefirió el calibre M.

  11. Teens could get new message on waiting for sex. Sex education.

    Science.gov (United States)

    1997-04-21

    It's best to wait until you are older to have sex. But if you decide to have intercourse, use a condom. We'll show you how. That's the message most New Jersey teens get in their sex education classes. It's the law. But a new source of federal funding could help advocates of "abstinence-only" education find a way around that requirement. The state Department of Health and Senior Services is considering whether to apply for federal money limited to programs teaching teens that abstinence is the only certain way to prevent pregnancy and avoid contracting sexually transmitted diseases, including HIV. The federally funded programs also would have to teach that sex before marriage is morally wrong. About $50 million for these abstinence-only programs was quietly tucked into the welfare bill that President Clinton signed into law in 1996. New Jersey is eligible to receive $843,000. The health department is hearing from people on both sides of the issue, said Celeste Wood, who plans to submit a report to Health Commissioner Len Fishman by the end of the month. Fishman will then decide whether New Jersey should apply for the money, she said. Historically, debate between "comprehensive" and "abstinence-only" sex education has centered around the classroom and education department. Comprehensive programs teach both abstinence and contraception. Abstinence-only programs prohibit discussion of contraception. Comprehensive education advocates have won that battle in New Jersey public schools. The state's core curriculum standards currently call for schools to teach teens about both abstinence and contraception. But the new federal money is being funneled through state health departments. "This skates around the schools by bringing the money in through the public health arena," said Daniel Daley, director of public policy for the Sexuality Information and Education Council of the US. "They are trying to influence community-based programs and make an end-run around the schools

  12. Parental roles in the development of obesity in children: challenges and opportunities

    Directory of Open Access Journals (Sweden)

    Danford CA

    2015-04-01

    Full Text Available Cynthia A Danford,1 Celeste M Schultz,2 Donna Marvicsin2 1Department of Health Promotion and Development, University of Pittsburgh, School of Nursing, Pittsburgh, PA, USA; 2Department of Health Promotion/Risk Reduction, University of Michigan, School of Nursing, Ann Arbor, MI, USA Background: The prevalence of childhood obesity has become a global concern and evolves from the complex interaction of multiple factors. In particular, the influence of socioeconomic status and ethnicity when combined with family dynamics are important, yet remain inconsistent in their association with childhood obesity. Parents, as influential family members, play a primary role in the development of their children’s eating and activity behaviors that may contribute to increased weight. This integrative review 1 examines the parental role in the development of childhood obesity and 2 identifies implications for health programs and policies. Method: Systematic searches using five databases followed by a lateral search were conducted between April and June 2014. Inclusion criteria included empirical research published in the last 5 years addressing the role that parents with children 12 years and younger play in their child being or becoming obese. Nineteen publications were identified. Results: Six themes related to the association between parental role and childhood obesity emerged from our review. These themes included parenting style, parent influence on feeding, modeling, self-efficacy, concern, and bidirectional interaction of the parent-child dyad. Parenting style, modeling, and self-efficacy were not consistently associated with childhood obesity. Parental concern, however, was linked to specific feeding practices. Parental restriction and pressure to eat certain foods were both found to be inversely related to a child’s weight status. Parent’s role in promoting activity was infrequently addressed. Conclusion: When addressing eating and activity behaviors

  13. Resonances and Tides in Natural Satellites Systems. (Breton Title: Ressonâncias e Marés em Sistemas de Satélites Naturais.) Resonancias y Mareas en Sistemas de Satélites Naturales

    Science.gov (United States)

    Callegari, Nelson, Jr.

    2006-12-01

    In this work we describe some aspects of the dynamics of the mean-motion resonances. Emphasis to the case of resonances between regular satellites of the giant planets will be given, even so some aspects of the physics of the resonances in extra-solar planetary systems are also briefly treated. The role of the resonances in satellites systems is discussed through examples, showing how certain resonances, and its relations with the tidal dissipation effects, can be the key of the explanation of some phenomena still not explained in the Solar System. Amongst some examples we highlight the problem of the resurfacing of Enceladus, the existence of active volcanoes in Io, and the possible existence of the subsurface ocean in Europe. This work has as objective the divulgation of some topics in Celestial Mechanics and Planetary Sciences for an undergraduate public in exact sciences, as Astronomy and Physics, and not their detailed description. Neste trabalho descrevemos alguns aspectos da dinâmica de ressonâncias de movimentos médios. Será dada ênfase maior ao caso de ressonâncias entre satélites regulares dos planetas gigantes, embora alguns aspectos da física das ressonâncias em sistemas planetários extra-solares também sejam discutidos brevemente. A importância do estudo de ressonâncias em sistemas de satélites é discutida mais detalhadamente através de exemplos, mostrando como certas ressonâncias e suas relações com efeitos de dissipação de maré podem ser a chave de parte da explicação de alguns fenômenos ainda não explicados no Sistema Solar. Dentre vários exemplos destacamos o problema da remodelagem da superfície do satélite Enceladus, a existência de vulcões ativos em Io, e a possível existência do oceano subterrâneo em Europa. Este trabalho tem como objetivo a divulgação de alguns tópicos de Mecânica Celeste e Planetologia para um público de nível de graduação em disciplinas na área de exatas, em especial Astronomia e F

  14. Astronomical Perception of the Secondary School's Students in São Paulo's State School in Suzano City. (Spanish Title: Percepción Astronómica de Alumnos de la Enseñanza Media de la Red Estatal de San Pablo en la Ciudad de Suzano.) Percepção Astronômica de um Grupo de Alunos do Ensino Médio da Rede Estadual de São Paulo da Cidade de Suzano

    Science.gov (United States)

    França de Oliveira, Edilene; Voelzke, Marcos Rincon; Amaral, Luis Henrique

    2007-12-01

    año y 20,6% tenían la idea de cuales son los objetos celestes más cercanos de la Tierra. En contraposición, 67,6% clasificaron correctamente el Sol como una estrella; 55,9% relacionaron el Big Bang al origen del Universo; solamente 20,6% identificaron un año-luz como unidad de distancia y 32,4% reconocieron una estrella fugaz como meteoro. El presente análisis fue expandido para otros grupos de la Enseñanza Media, no solamente del período nocturno, sino también diurno de la misma escuela. En esta primera fase se nota el pequeño conocimiento de los alumnos sobre eventos astronómicos y principalmente la gran confusión sobre el significado correcto de los términos astronómicos populares. Embora a Astronomia seja uma das ciências mais antigas da humanidade e muitos dos conceitos astronômicos serem populares, observa-se que uma parcela significativa dos estudantes encontra-se à margem dessas informações. O presente trabalho visa analisar o nível de conhecimento básico dos alunos do Ensino Médio da Rede Estadual da cidade de Suzano quanto aos fenômenos astronômicos que os rodeiam. Para tanto foi elaborado um formulário constando de questões de múltipla escolha, aplicado no primeiro ano noturno da Escola Estadual Batista Renzi. Num espaço amostral de 34 alunos constatou-se que apenas 29,4% compreendiam a sucessão dos dias; 20,6% explicaram corretamente as estações do ano e 20,6% tinham idéia de quais são os objetos celestes mais próximos da Terra. Em contraposição, 67,6% classificaram corretamente o Sol como estrela; 55,9% relacionaram o Big Bang à origem do Universo; apenas 20,6% identificaram um ano-luz como unidade de distância e 32,4% reconheceram uma estrela cadente como meteoro. A presente análise foi expandida para mais 310 alunos de outras classes de Ensino Médio, não somente do período noturno, mas também diurno da mesma escola. Nesta primeira fase nota-se o pequeno discernimento dos alunos sobre eventos astronômicos e

  15. The Understanding of Astronomy Concepts by Students from Basic Education of a Public School. (Spanish Title: El Entendimiento de Conceptos de Aastronmía Por Los Alumnos de Educación Básica en Una Escuela Pública.) O Entendimento de Conceitos de Astronomia Por Alunos da Educação Básica: O Caso de Uma Escola Pública Brasileira

    Science.gov (United States)

    Iria Machado, Daniel; dos Santos, Carlos

    2011-07-01

    movimiento de la Luna, el movimiento aparente del Sol sobre la esfera celeste, los eclipses, las dimensiones y las distancias en el Universo, el brillo de las estrellas y su observación de la Tierra. Si bien ha habido un pequeño progreso en la proporción de respuestas aceptables científicamente cuando se cotejó el octavo grado de la enseñanza primaria con el quinto, y el último año de la enseñanza secundaria con el primero, se observó un predominio de las concepciones alternativas en relación a la mayoría de los temas explorados, que continuó hasta los últimos años de la educación básica. Una comparación con los datos encontrados en investigaciones realizadas en otros contextos socioculturales revelaron, en muchos aspectos, conceptos y dificultades similares expresadas por los estudiantes. Apresentam-se os resultados de uma investigação sobre a compreensão de conceitos astronômicos básicos, da qual participaram 561 estudantes da quinta série do Ensino Fundamental ao terceiro ano do Ensino Médio de uma escola pública da cidade de Foz do Iguaçu. Um teste com 20 questões de múltipla escolha foi aplicado para identificar as concepções mais comuns expressadas pelos alunos. Esse instrumento de coleta de dados foi elaborado com base na literatura sobre concepções alternativas e abordou os seguintes temas: o ciclo dia-noite; os fusos horários; as estações do ano; as fases da Lua; o movimento da Lua; o movimento aparente do Sol na esfera celeste; os eclipses; as dimensões e distâncias no Universo; o brilho das estrelas e sua observação da Terra. Embora se tenha verificado um pequeno progresso na proporção de respostas cientificamente aceitáveis ao se cotejar a oitava série do Ensino Fundamental com a quinta, e a terceira série do Ensino Médio com a primeira, houve o predomínio de concepções alternativas em relação à maior parte dos temas explorados, as quais persistiram até o último ano da Educação Básica. A comparação com

  16. Apparent Motion of the Sun, Shadows of Objects and Measurement of Time in the View of Seventh Grade Students of Middle School. (Breton Title: Movimento Aparente do Sol, Sombras dos Objetos e Medição do Tempo na Visão de Alunos do Sétimo Ano do Ensino Fundamental.) Movimiento Aparente del Sol, Sombras de los Objetos y Medición del Tiempo en la Visión de Estudiantes del Séptimo Grado del Ciclo Pirmario

    Science.gov (United States)

    Iria Machado, Daniel

    2013-07-01

    The apparent motion of the Sun on the celestial sphere and the behavior of the shadows of objects over time are observable phenomena in everyday life. However, students often do not have a proper understanding of such occurrences, and can even display misconceptions about them. Therefore, we performed a research in order to know students' notions about these subjects and to evaluate the contribution to their understanding brought about by an activity performed with an interactive sundial in an informal learning environment. We investigated the ideas of 43 students from the seventh grade of middle school by applying a test with open questions before and after an activity with an analemmatic sundial, conducted by a monitor. A significant proportion of students were initially unaware of most of the phenomena treated. The intervention performed helped the students to assimilate new concepts, providing the contact with new phenomena and to a lesser degree, the development of explanations about them, indicating an educational potential of this action. However, the contribution to the understanding of some of the ideas explored was small, pointing to the need to make additional observations, studies and discussions. O movimento aparente do Sol na esfera celeste e o comportamento das sombras dos objetos com o passar do tempo são fenômenos observáveis no dia a dia. No entanto, muitas vezes os estudantes não possuem uma compreensão adequada de tais ocorrências, podendo inclusive exibir concepções alternativas a seu respeito. Por isso, efetuou-se uma pesquisa com o intuito de conhecer as noções dos alunos sobre esses temas e avaliar a contribuição para seu entendimento propiciada por uma atividade feita com um relógio de Sol interativo, em um ambiente de ensino informal. Foram investigadas as ideias de 43 alunos do sétimo ano do Ensino Fundamental mediante a aplicação de um teste com questões abertas antes e depois de uma atividade com um relógio de Sol

  17. The Shadow of a Gnomon Along a Year: Routine Observations and Teaching of Apparent Motion of the Sun and the Four Seasons. (Spanish Title: La Sombra de un Gnomon lo Largo de un Año: Observaciones de Rutina y la Enseñanza del Movimiento Aparente del Sol y Las Cuatro Estaciones.) A Sombra de um Gnômon ao Longo de um Ano: Observações Rotineiras e o Ensino do Movimento Aparente do Sol E das Quatro Estações

    Science.gov (United States)

    Trogello, Anderson Giovani; Danhoni Neves, Marcos Cesar; de Carvalho Rutz da Silva, Sani

    2013-12-01

    Many misconceptions are recognized among the various groups of students, especially in the elementary school. Among them, the apparent motion of the Sun, in spite of its daily occurrence, is subject to varied interpretations. Thus, the observation and recording of the motion of the stars in the celestial vault is a necessary task for astronomy education. The work presented here proposes the presentation of the results of observations of the apparent movement of the sun by marking the shadow of a vertical gnomon by the students in a class of sixth graders of elementary rural school of Paraná. The project itself was conducted in four stages, on dates near the March equinox, the June solstice, the September equinox and the December solstice. In addition, lectures were developed in the classroom. Such methods sought to build concepts around the apparent movement of the Sun and the alternation of the seasons. Given the results of the activities, an evaluation was applied and the data demonstrated a desired student learning such as: the recognition of the cardinal points, the description of the apparent solar motion and the occurrence of the seasons and their alternation from astronomical observations at naked eye. Muchos conceptos aternativos son conocidos entre los distintos grupos de alumnos, sobre todo en la educación básica. Entre ellos, el movimiento aparente del Sol, por más cotidiano que sea, se presta a interpretaciones variadas. Por lo tanto, observar y registrar el movimiento de las estrellas en la bóveda celeste se torna una tarea necesaria para la educación en astronomía. El trabajo que aquí se presenta propone la presentación de los resultados de la observación del movimiento aparente del sol a través de la marcación de la sombra del gnomon vertical a cargo de los estudiantes en una división de sexto grado de de la escuela primaria rural de Paraná. El proyecto en sí se llevó a cabo en cuatro etapas, en fechas cercanas al equinoccio de marzo

  18. Scattering of electromagnetic waves by an non-uniform cylindrical plasma; Diffusion coherente d'une onde electromagnetique par un cylindre de plasma inhomogene

    Energy Technology Data Exchange (ETDEWEB)

    Faugeras, P E [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires. Groupe de recherches sur la fusion controlee

    1967-07-01

    (surfaces d'onde paralleles a l'axe du cylindre). Ceci permet de relier les resultats theoriques aux diagrammes de diffraction experimentaux, et aussi d'expliquer les phenomenes, de diffraction qui faussent l'interpretation des mesures par interferometrie hyperfrequence. Ces resultats, joints a la possibilite de mesurer exactement le champ diffracte (ce que nous avons montre avec des cylindres dielectriques et metalliques) conduisent a une nouvelle methode de diagnostic d'un plasma, basee sur la diffraction. Sans limitations theoriques, cette methode est applicable la ou les methodes hyperfrequences classiques ne le sont pas (diametre du plasma inferieur a 10 longueurs d'onde).Cette methode a ete experimentee sur plasma a la pression atmospherique, avec une onde incidente de 2 mm. Le plasma est engendre par le jet laminaire d'une torche a plasma, fonctionnant avec de l'helium ou de l'argon ensemence au potassium (la densite peut ainsi varier de facon continue entre 10{sup 11} et 10{sup 15} e/cm{sup 3}). On donne egalement quelques diagrammes de diffraction par ce plasma, releves pour differents champs incidents, et interpretes par les resultats theoriques precedents. (auteur)

  19. Experimental study of the hydrodynamic instabilities occurring in boiling-water reactors; Etude experimentale des instabilites hydrodynamiques survenant dans les reacteurs nucleaires a ebullition

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-10-01

    The subjects is an experimental out-of pile loop study of the hydrodynamic oscillations occurring in boiling-water reactors. The study was carried out at atmospheric pressure and at pressure of about 8 atmospheres, in channels heated electrically by a constant and uniform specified current. In the test at 8 atmospheres the channel was a round tube of approximately 6 mm interior diameter. At 1 atmosphere a ring-section channel was used, 10 * 20 mm in diameter, with an inner heating tube and an outer tube of pyrex. It was possible to operate with natural convection and also with forced convection with test-channel by-pass. The study consists of 3 parts: 1. Preliminary determination of the laws governing pressure-drop during boiling. 2. Determination of the fronts at which oscillation appears, within a wide range of the parameters involved. 3. A descriptive study of the oscillations and measurement of the periods. The report gives the oscillation fronts with natural and forced convection for various values of the singular pressure drop at the channel inlet and for various riser lengths. The results are presented in non-dimensional form, which is available, in first approximation, for all geometric scales and for all fluids. Besides the following points were observed: - the wall (nature and thickness) can be an important factor ; - oscillation can occur in a horizontal channel. (author) [French] II a ete effectue une etude experimentale, en boucle hors-pile, des oscillations hydrodynamiques survenant dans les reacteurs a ebullition. L'etude a ete effectuee a la pression atmospherique et a une pression voisine de 8 atmospheres dans des canaux chauffes electriquement a puissance imposee constante et uniforme. Dans les essais a 8 atmospheres le canal etait un tube circulaire de diametre interieur 6 mm environ. A 1 atmosphere le canal etait de section annulaire 10 * 20 mm avec un tube interieur chauffant et un tube exterieur en pyrex. Le fonctionnement etait possible

  20. Study of the artificial radioactivity of the marine medium using gamma spectrometry (1962-1966); Etude de la radioactivite artificielle du milieu marin par spectrometrie gamma (1962-1966)

    Energy Technology Data Exchange (ETDEWEB)

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

    1969-07-01

    The results described in this study are relative to the artificial radioactivity of such elements as zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 and praseodymium-144 which were present in the atmospheric fallout between 1962 and 1964, and their incidence in superficial marine waters. Various physical, chemical or biological processes are studied by a high sensitivity gamma ray spectrometry technic, using those radioelements as 'tracers'. The change of state in sea water of an important fraction (about 50 per cent) of the radioactive particles going into the soluble phase - this phenomenon was not expected for those radioelements - controls the processes of accumulation in the planktonic biomass and the diffusion towards deeper waters. On the other hand, an 'in situ' spectrometry method is described. It enables the direct measurement in the sea of very low concentrations of some gamma ray emitters. The application of this method has made possible to carry out numerous observations in the surface waters of the Western Mediterranean sea and in the Bay of Biscay. It is shown that the mixing depth is closely connected to the depth of the thermocline. An accumulation process at this level is observed. The diffusion coefficients are similar to the thermal turbulent coefficient. The existence during several months of 'compartments' is established for the surface waters of the Bay of Biscay. From the establishment of the budget of fall-out, a comparative study shows that the rate of radioactive fallout on the maritime zone considered is always two to three times higher than on the neighbouring continental regions. Several explanations of this phenomenon are discussed. (author) [French] Les resultats decrits dans cette etude concernent la radioactivite artificielle sous forme de zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 et praseodyme-144 apportee par la retombee atmospherique entre 1962 et 1964 et les

  1. Corrosion of copper by chlorine trifluoride; Corrosion du cuivre par le trifluorure de chlore

    Energy Technology Data Exchange (ETDEWEB)

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

    1966-07-01

    chlore a ete effectuee, et controlee par chromatographie gazeuse, microsublimation et spectrographie infra-rouge. Les essais ont porte sur des cuivres de differentes puretes, principalement sur le cuivre a 99,999, sous forme de monocristaux. Ils ont comporte des cinetiques et la caracterisation des produits de corrosion dans differentes conditions de temperature et de pression. Les cinetiques ont montre des reactions du meme ordre de grandeur que celles obtenues avec le fluor-element. A pression atmospherique, il se forme du fluorure cuivrique et du chlorure cuivreux. La presence de ce compose permet d'ecarter definitivement l'assimilation du ClF{sub 3} a un simple agent fluorant. Aux basses pressions, un compose inconnu a ete caracterise. Il existe une tres forte presomption pour qu'il s'agisse du fluorure cuivreux instable, qui n'a pas pu etre encore isole. Un phenomene de germination a ete mis en evidence, montrant les analogies des phases initiales de fluoration avec celles de l'oxydation. Des effets importants resultant de la dissociation des fluorures de cuivre et de la solubilite du chlore dans ce metal ont ete mis en evidence. En dernier lieu, des essais ont montre l'influence considerable de la purete de la phase gazeuse et de la nature des parois sur les vitesses de corrosion qui peuvent dans certains cas etre multipliees par plusieurs puissances de dix. (auteur)

  2. A study of the fluorescence of the rare gases excited by nuclear particles. Use of the principle for the detection of nuclear radiation by scintillation; Etude de la fluorescence des gaz rares excites par des particules nucleaires. Utilisation pour la detection des rayonnements nucleaires par scintillation

    Energy Technology Data Exchange (ETDEWEB)

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

    1959-12-15

    In the first part is studied the properties of atoms excited by the passage of {alpha} particles through the various rare gases at atmospheric pressure. A spectral analysis of the emitted light showed that certain impurities play an important part in producing the fluorescence, and it has led to the conclusion that the light emission contains at least two components - one very short - lived due to the direct deexcitation of the rare gas, the other relatively slower due to the energy transfers to the impurity. The measurement of the life-time of the excited states has confirmed this foregoing hypothesis, the rapid part of the impulse is extremely short: less than 2,25.10{sup -9} s in the case of xenon; the slower part has a life-time depending directly on the nitrogen concentration, nitrogen being the impurity giving the largest effect in all cases. The study of rare gases under the influence of an electric field has made it possible to show that the amount of light produced by an {alpha} particle can be multiplied (by 60, for example, in a field of 600 V:cm) so that the luminescent efficiency is greater than in the case of INaTI. In the second part the characteristics of the rare gases acting as scintillators is examined, the most important property being the absence of fluorescence saturation when the intensity of the excitation incident on the gas is very large. This, together with the very short time of scintillation has made it possible to study a certain number of nuclear physical applications (heavy particle energy-measurements, kinetic studies on nuclear reactors, neutron spectroscopy). (author) [French] On etudie dans la premiere partie les proprietes des atomes excites par le passage de particules {alpha} dans les differents gaz rares a la pression atmospherique. L'etude spectrale de la lumiere emise a montre que certaines impuretes jouent un role considerable dans la fluorescence et on a ete amene a penser que l'emission de lumiere comporte au moins deux

  3. The Meteoritical Quincentennial: The Stone of Ensisheim 1492-1992

    Science.gov (United States)

    Marvin, U. B.

    1992-07-01

    of God, because never before had such a thing been heard, or seen, or written about. Von der Muhll (1961) and others have asked how such statements could be made when Pliny the Elder wrote of fallen stones as early as the 1st century A.D., and Heynlin de Lapide, at nearby Basel, was translating Pliny's works at the time of the fall. However, expressions such as "never before heard, seen, or written about," spiced the reports of Medieval travelers struggling to describe the marvels of far-off lands. In this instance, the phrases described a marvel that burst upon the people of the upper Rhineland in the course of their daily routines. In truth, nothing ever written could have prepared them for the incandescent fireball, resounding explosion, and the black stone that plunged to Earth at Ensisheim. Unimaginative Eyewitnesses. A boy saw the stone fall and a crowd dug it out of a wheat field. In 1800, the chemist, Charles Barthold, rejected the eyewitness story and concluded that the stone was a common type of rock that could have washed down from a mountainside. In 1803, after meteorites, including the Ensisheim stone, had become accepted as authentic natural phenomena, Joseph Izarn wrote that the boy's testimony should be believed because ignorant persons like him have no imagination and could not possible invent tales about stones from the sky. Izarn's opinion was not eccentric; numerous writings show that it reflected a centuries-old tradition of placing special value on observations by unschooled witnesses. References: Brant S. (1492) Flugblatt, J. von Ople, Basel, 1 p. Izarn J. (1803) Lithologie Atmospherique, Delalain Fils, Paris, 422 pp. Marvin U. B. (1992) Meteoritics 27, 28-72. Newton H. A. (1891) Comptes Rendus Acad. Sci. 113, 234. Muhll Th. von der (1975) Donnerstein von Ensisheim, Birkhauser Verlag, Basel, 42 pp. Schedel H. (1493) Nuremberg Chronicle, A. Korberger, Nuremberg, 299 pp.

  4. Disposal of Waste into the Atmosphere; Elimination des Dechets Radioactifs dans l'Atmosphere; 0423 0414 0410 ; Evacuacion de Desechos Radiactivos en la Atmosfera

    Energy Technology Data Exchange (ETDEWEB)

    Schulte, H. F. [Health Division, Los Alamos Scientific Laboratory, University of California, Los Alamos, NM (United States)

    1960-07-01

    The atmosphere can be compared to the hydrosphere and the lithosphere as a recipient of wastes, but the presence of airborne wastes is of more immediate concern to human life. There are two very distinct problems presented by atmospheric pollution, (1) that in the immediate vicinity of a plant and (2) the world-wide problem from long-term, widespread air pollution. Short- range problems have existed for many years as a result of non-radioactive wastes such as coal-smoke, sulphur dioxide and hydrogen fluoride. However, only in recent years has this problem received intense scientific study. Meteorological conditions play an important role in this problem. In some cases emission rates have been controlled in keeping with meteorological predictions. However, the basic solution is still that of reducing emission rates to the lowest possible values. (author) [French] L'atmosphere peut etre comparee a l'hydrosphere et a la lithosphere en tant que receptacle eventuel de dechets, mais la presence de dechets en suspension dans l'air est plus preoccupante pour la vie humaine. La pollution atmospherique pose deux problemes nettement distincts: 1) un probleme de portee limitee concernant le voisinage immediat d'une usine, et 2) un probleme de portee mondiale, savoir la pollution largement repandue, a long terme, de l'atmosphere. Des problemes de portee limitee se sont poses depuis de nombreuses annees ; ils sont lies a la presence dans l'atmosphere de dechets non radioactifs, tels que les fumees produites par le charbon, l'anhydride sulfurique et l'anhydride fluorhydrique. Cependant, ce n'est que recemment que ce probleme a ete soumis a une etude scientifique poussee. Les conditions meteorologiques jouent la un role important. Dans certains cas, les intensites d'emission ont ete controlees en tablant sur les previsions meteorologiques. Toutefois, la solution fondamentale est encore de reduire l'intensite d'emission a la plus faible valeur possible. (author) [Spanish] Si bien

  5. On some uses of the recording op fission fragments occurring in insulators; Sur quelques utilisations de l'enregistrement des fragments de fission dans les isolants

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-07-01

    thermiques: on peut mesurer des flux integres s'etendant de 10{sup 3} a 10{sup 21} n/cm{sup 2}, suivant la methode utilisee; - dosimetrie de neutrons rapides: en utilisant des sources de fragments de fission a seuil, on peut facilement mesurer des doses d'interet biologique de l'ordre du rem; - dosage d'impuretes fissiles en tres faible concentration: on peut determiner des concentrations atomiques de l'ordre de 10{sup 9}, limite jamais atteinte par les procedes usuels; - etude des elements fissiles contenus dans les poussieres atmospheriques. On donne ensuite brievement les resultats d'un essai d'automatisation du comptage des traces par mesure de la resistivite electrique de la membrane irradiee. On expose enfin les avantages et les inconvenients de ces detecteurs solides, notamment par rapport aux emulsions nucleaires dont les utilisations sont a peu pres identiques. (auteur)

  6. EL3 reactor description and safety analysis report; Pile EL3, rapport descriptif et de surete

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1969-02-01

    ). Elle est concue pour fonctionner a une puissance thermique maximale de 20 mW. Elle fournit un flux maximal thermique de 10{sup 14} neutrons/cm{sup 2}/sec. Elle dispose de nombreux dispositifs experimentaux. La pile EL-3 est contenue, avec ses auxiliaires des circuits des fluides, dans une enceinte etanche, en legere depression. Le circuit d'eau lourde de refroidissement primaire est entierement contenu dans cette enceinte. Son refroidissement est assure, par l'intermediaire d'un circuit secondaire en eau legere, par des refrigerants atmospheriques. Les circuits de ventilation de l'enceinte etanche et du bloc pile ne rejettent l'air a l'exterieur, en fonctionnement normal, par une cheminee particulierement etudiee, qu'apres filtrage et eventuellement dilution. La contamination eventuelle de l'eau legere, ou de l 'air, par des produits actifs, est controlee en permanence, pour permettre l'arret du reacteur et eviter le rejet a l'atmosphere de produits dangereux. La pile El3, mise en chantier en mai 1955, a diverge en juillet 1957, effectue sa premiere montee en puissance en decembre 1957 et a atteint sa pleine puissance en avril 1958. La mise en place du combustible actuel (cristal de Neige) s'est effectue durant l'ete 1964. Pile a vocation experimentale, elle est utilisee pour des etudes theoriques et technologiques par irradiation de materiel dans les canaux experimentaux et dans les cellules memes du coeur, avec possibilites de constituer des boucles independantes (en ce qui concerne les fluides de refroidissement). Trente canaux verticaux sont reserves a la fabrication de radioelements artificiels. (auteur)

  7. Influence of heat treatment in {beta} and {gamma} phases on the microscopic structure of uranium; Influence des traitements thermiques en phases {beta} et {gamma} sur la structure micrographique de l'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Robillard, A

    1958-06-02

    A new method of microscopic examination of uranium is described. Electrolytic polishing and etching are carried out in an acetic acid-chromic acid bath. Atmospheric or anodic oxidation of the polished surface produces films which follow exactly changes in the structure of the underlying metal. This method is very sensitive to small variations of orientation in polygonized crystals. Using this method of examination of uranium, it was found that annealing U in the {gamma} phase followed by a cooling at a rate dependent of the annealing temperature, causes the formation of substructures different from those due to the polygonization of {alpha}-U. The substructures are indicated by the concentration of impurities on the dislocations induced by the stresses accompanying the allotropic transformation {gamma} {yields} {beta}. Similar treatment of the U-1.4% Cr alloy in which the {beta} phase is stabilized at room temperature, confirms this explanation. In addition to the polygonization substructures, sharp discontinuities can be observed in the network of sub- boundaries as a fine white edging. The comparison of these with the structure revealed by thermal etching in vacuum suggest that there are traces of the grain boundaries of the {gamma} phase. The method of etching followed by oxidation shows a haloed phase identified as UH{sub 3}. The conditions of appearance and disappearance of this phase are studied. The sensitivity of this method of detecting the last traces of H in U is very high. The dependence of the hydrogen content on the tensile properties of uranium metal was also studied. (author) [French] Une methode nouvelle d'examen micrographique de l'uranium a ete mise au point. Le polissage electrolytique et le 'gravage' sont effectues dans un bain acide acetique-acide chromique. L'oxydation atmospherique ou anodique de la surface polie conduit a la formation de couches epitaxiques d'oxyde. Cette methode est particulierement sensible aux faibles variations d

  8. The analysis of mixtures of ortho and para-hydrogen and the catalytic conversion o.H{sub 2} {yields} p.H{sub 2}; Analyse des melanges d'ortho et para-hydrogenes et conversion catalytique o.H{sub 2} {yields} p.H{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Botter, F; Dirian, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1956-07-01

    'une part a la temperature ambiante, la difference de quelques pour cent entre Ies conductibilites thermique de l'ortbo-hydrogene et du para-hydrogene s'etant averee tres suffisante, et d'autre part par analyse continue avec enregistrement, le gaz etant a pression atmospherique. Occasionnellement, on a experimente un catharometre de type industriel dont l'utilisation permettrait une grande extension de cette methode analytique, qui s'est montre satisfaisant. On a verifie que la reaction de conversion paramagnetique obeissait a une cinetique du premier ordre. Un certain nombre de substances absorbantes ont ete testees, parmi lesquelles les charbons, souvent utilises en laboratoire pour la production de para-hydrogene, se sont reveles les moins actifs. Un catalyseur oxyde de chrome-alumine a ete prepare d'apres les donnees de la litterature; son activite catalytique est tres grande. Par ailleurs quelques observations quant a l'influence des gaz absorbes sur l'activite catalytique sont rapportees; la comparaison avec les resultats tires de la litterature est malaisee en raison de l'incertitude sur la nature physico-chimique des absorbants utilises dans les deux cas. Enfin le rapport contient des donnees bibliographiques relatives au proprietes des deux varietes d'hydrogene, a leur dosage et aux differents mecanismes d'interconversion. (auteur)

  9. Study of the artificial radioactivity of the marine medium using gamma spectrometry (1962-1966); Etude de la radioactivite artificielle du milieu marin par spectrometrie gamma (1962-1966)

    Energy Technology Data Exchange (ETDEWEB)

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

    1969-07-01

    atmospherique entre 1962 et 1964 et les incidences de cette retombee dans les eaux marines superficielles. Considerant les radioelements etudies comme des 'traceurs' dans le milieu marin, divers processus physiques, chimiques ou biologiques ont ete etudies par spectrometrie gamma a haute sensibilite. Le passage en phase soluble dans l'eau de mer d'une fraction importante (environ 50 pour cent) de l'activite liee aux poussieres radioactives, phenomene qui n'etait pas previsible pour les radioelements etudies, gouverne les processus d'accumulation dans la biomasse planctonique et la diffusion vers les eaux plus profondes. Par ailleurs, une methode de spectrometrie 'in situ' permettant de mesurer directement dans la mer de tres faibles concentrations en certains radionuclides emetteurs gamma est decrite. L'application de cette methode a permis de nombreuses observations dans les eaux de surface de la Mediterranee occidentale et du Golfe de Gascogne. On montre quo la profondeur de melange est etroitement liee a celle de la thermocline. Un processus d'accumulation au niveau de celle-ci est constate. Les coefficients de diffusion sont voisins du coefficient de diffusion thermique turbulente. L'existence de compartiments qui subsistent pendant plusieurs mois dans la masse des eaux de surface du Golfe de Gascogne est mise en evidence. Grace aux bilans effectues, une etude comparative montre que le taux de retombees radioactives sur les surfaces maritimes est toujours deux a trois fois superieur a celui sur les regions continentales voisines. Diverses explications de ce phenomene sont discutees. (auteur)

  10. EL3 reactor description and safety analysis report; Pile EL3, rapport descriptif et de surete

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1969-02-01

    concue pour fonctionner a une puissance thermique maximale de 20 mW. Elle fournit un flux maximal thermique de 10{sup 14} neutrons/cm{sup 2}/sec. Elle dispose de nombreux dispositifs experimentaux. La pile EL-3 est contenue, avec ses auxiliaires des circuits des fluides, dans une enceinte etanche, en legere depression. Le circuit d'eau lourde de refroidissement primaire est entierement contenu dans cette enceinte. Son refroidissement est assure, par l'intermediaire d'un circuit secondaire en eau legere, par des refrigerants atmospheriques. Les circuits de ventilation de l'enceinte etanche et du bloc pile ne rejettent l'air a l'exterieur, en fonctionnement normal, par une cheminee particulierement etudiee, qu'apres filtrage et eventuellement dilution. La contamination eventuelle de l'eau legere, ou de l 'air, par des produits actifs, est controlee en permanence, pour permettre l'arret du reacteur et eviter le rejet a l'atmosphere de produits dangereux. La pile El3, mise en chantier en mai 1955, a diverge en juillet 1957, effectue sa premiere montee en puissance en decembre 1957 et a atteint sa pleine puissance en avril 1958. La mise en place du combustible actuel (cristal de Neige) s'est effectue durant l'ete 1964. Pile a vocation experimentale, elle est utilisee pour des etudes theoriques et technologiques par irradiation de materiel dans les canaux experimentaux et dans les cellules memes du coeur, avec possibilites de constituer des boucles independantes (en ce qui concerne les fluides de refroidissement). Trente canaux verticaux sont reserves a la fabrication de radioelements artificiels. (auteur)

  11. Experimental study of heat transfer and pressures drops for cans with spiral herring-bone fins; Etude experimentale du transfert de chaleur et des pertes de charges des gaines a ailettes helicoidales en chevron

    Energy Technology Data Exchange (ETDEWEB)

    Pelce, J; Francois, S; Houseaux, O; Pierre, B [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    experimentale. Les essais sont de trois types: essais en vraie grandeur, dans des conditions proches de celles existant dans le reacteur (flux constant, CO{sub 2} sous pression); essais en vraie grandeur mais a temperature de paroi constante, d'une mise en oeuvre beaucoup plus simple, et destines a une discrimination rapide entre les differents types de gaine; essais a grande echelle avec de l'air a la pression atmospherique pour une observation des phenomenes dans le detail. Pour chacune des gaines experimentees correspond un coefficient de pertes de charge, un coefficient d'echange thermique moyen Mo-bar et un coefficient d'echange minimum Mo{sub min} servant au calcul du point le plus chaud de la gaine; Mo{sub min} et Mo-bar sont relies par l'expression Mo{sub min} = Mo-bar * f{sub c} * f{sub l}, ou f{sub c} et f{sub l} sont respectivement des facteurs de singularites circonferentielle et longitudinale, determines apres un examen statistique de l'ensemble des temperatures mesurees sur chaque gaine. Les resultats sont rassembles sur une trentaine de tableaux et figures, les resultats les plus marquants etant resumes dans la conclusion. (auteurs)

  12. Developpement D'un Modele Climatique Regional: Fizr Simulation des Conditions de Janvier de la Cote Ouest Nord Americaine

    Science.gov (United States)

    Goyette, Stephane

    1995-11-01

    . Cette nouvelle gamme de modeles-interpolateurs imbriques qualifies d'"intelligents" fait partie de la famille des modeles dits "pilotes". L'hypothese directrice de notre etude est fondee sur la supposition que le climat de fine echelle est souvent gouverne par des forcages provenant de la surface plutot que par des transports atmospheriques de grande echelle spatiale. La technique que nous proposons vise donc a guider FIZR par la Dynamique echantillonnee d'un MCG et de la forcer par la Physique du MCG ainsi que par un forcage orographique de meso-echelle, en chacun des noeuds de la grille fine de calculs. Afin de valider la robustesse et la justesse de notre modele climatique regional, nous avons choisi la region de la Cote Ouest du continent nord americain. Elle est notamment caracterisee par une distribution geographique des precipitations et des temperatures fortement influencee par le relief sous-jacent. Les resultats d'une simulation d'un mois de janvier avec FIZR demontrent que nous pouvons simuler des champs de precipitations et de temperatures au niveau de l'abri beaucoup plus pres des observations climatiques comparativement a ceux simules a partir d'un MCG. Ces performances sont manifestement attribuees au forcage orographique de meso-echelle de meme qu'aux caracteristiques de surface determinees a fine echelle. Un modele similaire a FIZR peut, en principe, etre implante sur l'importe quel MCG, donc, tout organisme de recherche implique en modelisation numerique mondiale de grande echelle pourra se doter d'un el outil de regionalisation.

  13. Experimental study of the hydrodynamic instabilities occurring in boiling-water reactors; Etude experimentale des instabilites hydrodynamiques survenant dans les reacteurs nucleaires a ebullition

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-10-01

    The subjects is an experimental out-of pile loop study of the hydrodynamic oscillations occurring in boiling-water reactors. The study was carried out at atmospheric pressure and at pressure of about 8 atmospheres, in channels heated electrically by a constant and uniform specified current. In the test at 8 atmospheres the channel was a round tube of approximately 6 mm interior diameter. At 1 atmosphere a ring-section channel was used, 10 * 20 mm in diameter, with an inner heating tube and an outer tube of pyrex. It was possible to operate with natural convection and also with forced convection with test-channel by-pass. The study consists of 3 parts: 1. Preliminary determination of the laws governing pressure-drop during boiling. 2. Determination of the fronts at which oscillation appears, within a wide range of the parameters involved. 3. A descriptive study of the oscillations and measurement of the periods. The report gives the oscillation fronts with natural and forced convection for various values of the singular pressure drop at the channel inlet and for various riser lengths. The results are presented in non-dimensional form, which is available, in first approximation, for all geometric scales and for all fluids. Besides the following points were observed: - the wall (nature and thickness) can be an important factor ; - oscillation can occur in a horizontal channel. (author) [French] II a ete effectue une etude experimentale, en boucle hors-pile, des oscillations hydrodynamiques survenant dans les reacteurs a ebullition. L'etude a ete effectuee a la pression atmospherique et a une pression voisine de 8 atmospheres dans des canaux chauffes electriquement a puissance imposee constante et uniforme. Dans les essais a 8 atmospheres le canal etait un tube circulaire de diametre interieur 6 mm environ. A 1 atmosphere le canal etait de section annulaire 10 * 20 mm avec un tube interieur chauffant et un tube exterieur en pyrex. Le fonctionnement etait possible en

  14. Influence of heat treatment in {beta} and {gamma} phases on the microscopic structure of uranium; Influence des traitements thermiques en phases {beta} et {gamma} sur la structure micrographique de l'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Robillard, A

    1958-06-02

    A new method of microscopic examination of uranium is described. Electrolytic polishing and etching are carried out in an acetic acid-chromic acid bath. Atmospheric or anodic oxidation of the polished surface produces films which follow exactly changes in the structure of the underlying metal. This method is very sensitive to small variations of orientation in polygonized crystals. Using this method of examination of uranium, it was found that annealing U in the {gamma} phase followed by a cooling at a rate dependent of the annealing temperature, causes the formation of substructures different from those due to the polygonization of {alpha}-U. The substructures are indicated by the concentration of impurities on the dislocations induced by the stresses accompanying the allotropic transformation {gamma} {yields} {beta}. Similar treatment of the U-1.4% Cr alloy in which the {beta} phase is stabilized at room temperature, confirms this explanation. In addition to the polygonization substructures, sharp discontinuities can be observed in the network of sub- boundaries as a fine white edging. The comparison of these with the structure revealed by thermal etching in vacuum suggest that there are traces of the grain boundaries of the {gamma} phase. The method of etching followed by oxidation shows a haloed phase identified as UH{sub 3}. The conditions of appearance and disappearance of this phase are studied. The sensitivity of this method of detecting the last traces of H in U is very high. The dependence of the hydrogen content on the tensile properties of uranium metal was also studied. (author) [French] Une methode nouvelle d'examen micrographique de l'uranium a ete mise au point. Le polissage electrolytique et le 'gravage' sont effectues dans un bain acide acetique-acide chromique. L'oxydation atmospherique ou anodique de la surface polie conduit a la formation de couches epitaxiques d'oxyde. Cette methode est particulierement sensible

  15. Tritium Content of Rainwater from the Eastern Mediterranean Area; Teneur en tritium des eaux de pluie dans la region de la Mediterranee orientale; Soderzhanie tritiya v dozhdevoj vode, vzyatoj iz vostochnogo rajona sredizemnogo morya; Contenido del tritio en las aguas de lluvia de la zona del Mediterraneo oriental

    Energy Technology Data Exchange (ETDEWEB)

    Gat, J R; Karfunkel, U; Nir, A [Weizmann Institute of Science, Rehovoth (Israel)

    1962-01-15

    echantillons d'eaux de citerne accumulees pendant la saison des pluies de 1956/57 et 1957/58. Compte tenu de la date des essais thermonucleaires, des courants atmospheriques et de la saison locale des pluies, on peut conclure qu'il n'y a aucun transport tropospherique direct de tritium provenant de la zone des essais vers la region consideree. Les concentrations de tritium mesurees sont dues au passage de tritium des hautes altitudes dans les couches atmospheriques inferieures. On a evalue la duree moyenne du sejour dans l'atmosphere du tritium stratospherique provenant de diverses sources. Les constatations faites semblent prouver que le tritium ne se melange que lentement aux masses d'air de la stratosphere. Les differences constantes entre les concentrations de tritium a divers endroits sont expliquees en tenant compte des differentes situations qui sont a l'origine des pluies. On montre que le melange des masses d'air maritimes et continentales a une influence primordiale sur la teneur en tritium des eaux de pluie et que l'etendue de la mer Mediterranee est faible par rapport a l'ampleur des phenomenes meteorologiques en jeu. (author) [Spanish] Los autores analizaron unas 50 muestras de agua de lluvia recogidas durante los anos 1958 a 1960 en Israel y paises vecinos a fin de determinar su contenido de tritio por recuento gaseoso precedido de un enriquecimiento electrolitico. Entre las muestras figuraban algunas de precipitaciones aisladas, recogidas en dos estaciones en Israel y una en Chipre, asi como agua acumulada durante cada temporada de lluvia en una serie de lugares en Israel, Chipre, Turquia y Grecia. Ademas se analizaron muestras de aguas de cisterna representativas de las lluvias caidas durante las temporadas 1956-1957 y 1957-1958. La configuracion de las corrientes atmosfericas y la relacion cronologica que existe entre los ensayos de armas termonucleares y la temporada local de lluvias indican que no se produce ningun transporte troposferico directo de tritio

  16. As cores no ambiente de terapia intensiva: percepções de pacientes e profissionais Los colores en el ambiente de cuidados intensivos: percepciones de pacientes y profesionales Colors in the intensive therapy environment: perceptions of patients and professionals

    Directory of Open Access Journals (Sweden)

    Nélio Barbosa Boccanera

    2006-09-01

    Full Text Available A utilização das cores no ambiente da Unidade de Terapia Intensiva - UTI pode interferir no bem-estar dos profissionais e clientes. Este estudo teve como objetivo analisar percepções de profissionais e pacientes quanto às cores utilizadas no ambiente de terapia intensiva, identificando aquelas consideradas agradáveis e desagradáveis. Trata-se de pesquisa descritivo-exploratória, com enfoque quanti-qualitativo. A amostra foi constituída de clientes internados e profissionais que trabalham em três UTIs de hospitais públicos localizados em Goiânia. As cores consideradas mais agradáveis para serem utilizadas em UTI foram o azul-claro e o verde-claro. Além dessas, apontaram o amarelo-claro, palha, cinza, rosa e goiaba. O vermelho e o preto foram consideradas as cores mais desagradáveis para um ambiente de UTI. Os profis-sionais e clientes referem preferência por cores variadas, as quais podem ser utilizadas no sentido de melhorar o clima da UTI.La utilización de los colores en el ambiente de la Unidad de Cuidados Intensivos - UCI puede interferir en el bienestar de los profesionales y clientes. En este estudio se tuvo como objetivo analizar las percepciones de profesionales y pacientes en cuanto a los colores utilizados en el ambiente de cuidados intensivos, identificando aquellas consideradas agradables y desagradables. Se trata de una investigación descriptivo-exploratoria, con enfoque cuanti-cualitativa. La muestra estuvo constituida de clientes internados y de profesionales que trabajan en tres UCIs de hospitales públicos localizados en Goiânia. Los colores considerados más agradables para ser utilizadas en UCI fueron el celeste y el verde claro. Además de ellos, señalaron el amarillo, paja, gris, rosado y guayaba. El rojo y el negro fueron considerados los colores más desagradables para un ambiente de UCI. Los profesionales y clientes refirieron preferencia por colores variados, los cuales pueden ser utilizados en el

  17. The role of PHD2 mutations in the pathogenesis of erythrocytosis

    Directory of Open Access Journals (Sweden)

    Gardie B

    2014-07-01

    Full Text Available Betty Gardie,1,2 Melanie J Percy,3 David Hoogewijs,4 Rasheduzzaman Chowdhury,5 Celeste Bento,6 Patrick R Arsenault,7 Stéphane Richard,1,8,9 Helena Almeida,6 Joanne Ewing,10 Frédéric Lambert,11 Mary Frances McMullin,12 Christopher J Schofield,5 Frank S Lee7 1Laboratoire de Génétique Oncologique de l'Ecole Pratique des Hautes Etudes, Villejuif, 2Unité Mixte de Recherche, Institut national de la santé et de la recherche médicale U892, Centre national de la recherche scientifique 6299, Centre de Recherche en Cancérologie Nantes/Angers, Université de Nantes, Nantes, France; 3Department of Haematology, Belfast City Hospital, Belfast, UK; 4Institute of Physiology and Zürich Center for Integrative Human Physiology, University of Zürich, Zürich, Switzerland; 5Department of Chemistry and Oxford Centre for Integrative Systems Biology, Chemistry Research Laboratory, University of Oxford, Oxford, UK; 6Department of Hematology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal; 7Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA; 8Institut national de la santé et de la recherche médicale U753, Institut de cancérologie Gustave Roussy (IGR, Villejuif, France; 9Faculté de Médecine Paris-Sud, Le Kremlin-Bicêtre, France; 10Heart of England NHS Trust, Birmingham, UK; 11Center for Human Genetics, Pathology Institute, UniLab-Lg, Molecular Haemato-Oncology Unit, CHU of Liege, Liege, Belgium; 12Department of Haematology, Queen's University, Belfast, UK Abstract: The transcription of the erythropoietin (EPO gene is tightly regulated by the hypoxia response pathway to maintain oxygen homeostasis. Elevations in serum EPO level may be reflected in an augmentation in the red cell mass, thereby causing erythrocytosis. Studies on erythrocytosis have provided insights into the function of the oxygen-sensing pathway and the critical proteins involved in the regulation

  18. ECT, rTMS, and deepTMS in pharmacoresistant drug-free patients with unipolar depression: a comparative review

    Directory of Open Access Journals (Sweden)

    Salviati M

    2012-01-01

    Full Text Available Amedeo Minichino¹, Francesco Saverio Bersani¹, Enrico Capra¹, Rossella Pannese¹, Celeste Bonanno², Massimo Salviati¹, Roberto Delle Chiaie¹, Massimo Biondi¹¹Department of Neurology and Psychiatry, Sapienza University of Rome, Rome, ²Aldo Moro University of Bari, Bari, ItalyBackground: Biological treatments are considered as additional options for the treatment of resistant unipolar depression. Controversial data exist about the efficacy and tolerability of three of the most used somatic treatments: electroconvulsive therapy (ECT, transcranial magnetic stimulation (rTMS, and deep transcranial magnetic stimulation (deepTMS. The aim of this review is to investigate and compare the efficacy and tolerability of these three techniques in drug-free patients with pharmacoresistant unipolar depression.Methods: Three independent reviewers extracted data and assessed the quality of methodological reporting of selected studies. The first outcome was the clinical response to the three different techniques defined as a percentage improvement of Hamilton Depression Rating Scale (HDRS. The second outcome was the evaluation of their neuropsychological effects. The third outcome was the evaluation of the number of remitted patients; remission was defined as an absolute HDRS-24 score of ≤11 or as an absolute HDRS-17 score of ≤8. Tolerability was the fourth outcome; it was evaluated by examining the number of dropped-out patients.Results: The comparative evaluation of HDRS percentage variations shows ECT as the most effective method after 4 weeks of therapy; on the other hand, a better efficacy is obtainable by deepTMS after 2 weeks of therapy. DeepTMS is the technique that gives the best improvement of cognitive performances. The percentage of remitted patients obtained with ECT treatment is the same obtained in the deepTMS group. Both techniques have a remitted patients percentage two times larger than the rTMS. DeepTMS shows a tolerability

  19. Occurrence of Cr-bearing beryl in stream sediment from Eskişehir, NW Turkey

    Directory of Open Access Journals (Sweden)

    Hülya Erkoyun

    2016-07-01

    berilio y aguamarinas color verde celeste, con bandas de espectroscopia infrarroja de buena nitidez. El análisis químico húmedo del berilio de Eskisehir mostró 61.28 % de SiO2, 15.13 % de Al2O3, 12.34 % de BeO, 0.18 % de Cr2O3, 1.49 % de MgO, 1.69 % de Na2O, 0.98 % de Fe2O3, y 0.008% de V2O3, lo que resulta en la formula (Al1.75Cr0.01Mg0.22Fe0.08(Be2.90Si6.00(Na0.32O18. Los elementos litófilos de ion grande (bario, estroncio, algunos metales de transición (cobalto, excepto níquel y los elementos de gran campo de fuerza (niobio, circonio e itrio en las corrientes de sedimentos que están con berilio mostraron un bajo contenido sobre las rocas metamórficas. Las formaciones de berilio aparecen controladas por fallas de cabalgamiento y fracturas que se yuxtaponen con las unidades ofiolíticas relacionadas con cromo y un régimen de reacciones metasomáticas. Estos cristales de berilio se han encontrado también en sedimentos detríticos que se derivan de los esquistos.

  20. Reseñas de Libros

    Directory of Open Access Journals (Sweden)

    Joaquín Piñeiro Blanca

    2009-12-01

    ngel del Arco BlancoSantana, Juan M., Paradigmas historiográficos contemporáneos. Barquisimeto, Fundación Buria, 2005, 196 pp.Páginas 223-225Israel Sanmartín BarrosSerafí Bernat i Martí, Joan; Gimeno i Bosch, Celestí (ed., Migración e interculturalidad. De lo global a lo local. Castellón de la Plana, Servicio de Publicaciones de la Universitat Jaume I, 2006, 281 pp.Páginas 225-227Alejandro Román AntequeraVali, Nasr, The Shia Revival: How Conflicts Within Islam Will Shape the Future. New York, W.W. Norton, 2006, 304 pp.Páginas 227-229Carlos L. Yordan

  1. Ílion, a Pátria dos Ventos: O uso da Meteorologia e da Astronomia na Ilíada * Ilion, la Patrie des Vents: l'utilisation de la Meteorologie et l'Astronomie dans l'Iliade

    Directory of Open Access Journals (Sweden)

    RAFAEL VIRGILIO DE CARVALHO

    2014-01-01

    Full Text Available Resumo: Na Grécia Antiga o céu era personificado como um dos deuses primordiais do panteão helênico. Como gerador de tudo o que existe, Urano (Céu abrigava em seu bojo as forças naturais que indicavam a presença dos deuses e dos titãs. Nessa direção, a observação de seus objetos - os metéoroi - era de inestimável valor para a cultura homérica. Homero iluminou as ações dos heróis da Ilíada por meio de analogias com os objetos celestes, os quais mais tarde no século IV a.C. mobilizariam os olhares de Platão e de Aristóteles. Os meteóroi, "objetos naturais suspensos no ar", foram descritos pelo poeta através de certas funções narrativas da epopeia, estruturando assim uma protometeorologia homérica. O presente trabalho procura então levantar certos padrões expressivos encontrados durante a leitura da Ilíada e algumas considerações que os problematizam de modo a iluminar o entendimento sobre tema.Palavras-chave: Mundo homérico – Meteorologia e astronomia – Crença – Mecanismos de linguagem. Résumé: Dans la Grèce antique, le ciel était personnifié comme l'un des dieux primordiaux du panthéon hellénique. Comme un générateur de tout ce qui existe, Uranus (le Ciel logé en elle les forces naturelles qui indiquaient la présence des dieux et des Titans. De cette façon, l'observation des ses objets - les meteóroi - a été d'une valeur inestimable à la culture homèrique. Homère éclarait les actions de l'Iliade grâce a des analogies avec les objets célestes, qui, plus tard dans l'IVe siècle av. J.-C., mobiliseraient les regards de Platon et d'Aristote. Les meteóroi, "les objets naturels en suspension dans l'air", ont été décrits par le poète à travers des certaines fonctions narratives de l'histoire, structurant ainsi une proto-météorologie homérique. Cet article cherche alors à soulever certaines normes de description trouvés au cours de la lecture de l'Iliade et quelques consid

  2. VizieR Online Data Catalog: New standards in 18th century astrometry (Lequeux, 2014)

    Science.gov (United States)

    Lequeux, J.

    2014-05-01

    named lacaillefund.dat. La Caille's complete survey of the southern sky (lacaisur.dat): During his stay in Cape Town in 1751-1752, La Caille made the first systematic survey of the sky ever, in the modern sense. 244 stars over 9766. La Caille's catalogue of zodiacal stars (lacaizod.dat): When La Caille returned from his southern expedition in 1754, he undertook the construction of a catalogue of zodiacal stars. Mayer's zodiacal catalogue (mayer.dat): At exactly the same time as La Caille, Tobias Mayer (1723-1762) in Gottingen undertook a similar catalogue of zodiacal stars, using a 6-feet radius mural quadrant made by John Bird (1709-1776). 200 stars over 998. Bradley's stellar catalogue (bradley.dat): James Bradley (1693-1762) is famous for his discovery of aberration and nutation. From 1750 to his death in 1762, he built a large stellar catalogue, from observations first with an old mural sector and after 1753 with the Bird 8-ft mural sector located in Greenwich, where it 215 stars over 3220. Piazzi's stellar catalogue (piazzi.dat): Giuseppe Piazzi (1746-1846) built a large catalogue containing 7646 stars from 1792 to 1813, observed in Palermo with an altazimuthal circle of Jesse Ramsden (1735-1800) can still be seen. 202 stars over 7646. Lalande's stellar catalogue (lalande.dat): L'Histoire celeste francaise de Lalande (Lalande 1801), which contains the unreduced observations of approximately 40,000 stars, is the first very large stellar catalogue. 198 stars over ~45000. (10 data files).

  3. Palacio de correos, telégrafos y oficinas públicas, en Cortina D'Ampezzo

    Directory of Open Access Journals (Sweden)

    Gellner, Edoardo

    1964-03-01

    auxiliar. En la otra parte de este piso, disponiendo de accesos independientes, está ubicada la sala de Audiencias del Juzgado. Se desarrollan en el segundo piso las dependencias del Juzgado: oficinas del juez, de los secretarios, sala de abogados, de estadística, archivo y registro. En el tercer piso están las oficinas de Hacienda y seguridad públicas. Y en el ático, los salones del círculo artístico, capaces para 120 personas, con bar, oficinas y aseos. El edificio ofrece toda su estructura de hormigón armado vista y abujardada. La policromía de los paneles de cerramiento, pintados de color azul celeste y rojo, y los revestimientos de alerce, con su color natural rojizo, contribuyen a romper el tono gris uniforme de la masa de hormigón armado y dan vivacidad a las fachadas.

  4. Health physics problems in the context of the development of industrial uses of nuclear energy; Les problemes de radioprotection devant le developpement de l'utilisation industrielle de l'energie nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Duhamel, F.; Menoux, A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    ou les moyens technologiques de protection sont multiples et complexes. Les etudes de surete des sites permettent de preciser les parametres de diffusion ou de reconcentration dans les divers milieux naturels de facon a permettre de prevoir le sort des effluents radioactifs depuis les installations qui en sont la source jusqu'a l'homme qui peut y etre expose. L'organisation de la surveillance de la radioactivite sur les sites nucleaires est liee tres etroitement aux etudes de surete. Parmi les nombreuses etudes a mener, on insistera plus particulierement sur les experiences de diffusion atmospherique dont le but est de preciser la valeur des parametres introduits par la theorie tout en permettant de tenir compte de facteurs complementaires. - les etudes hydrologiques, hydrogeologiques et oceanographiques, qui permettent de preciser le sort des ions radioactifs dans l'hydrosphere. - les experiences et etudes liees aux possibilites de rejet ou de stockage des dechets dans le sol. L'ensemble de ces travaux constitue un moyen complementaire, la radioprotection, qui etablit une liaison necessaire entre la surete nucleaire proprement dite laquelle concerne le fonctionnement meme des installations nucleaires, et la surveillance medicale laquelle concerne directement la sante de l'individu et de la population. En meme temps,la radioprotection donne a chacune de ces disciplines une independance qui accroit leur efficacite sur le plan de la securite. (auteurs)

  5. Comportment of various magnesium alloys in carbon dioxide under pressure, between 400 and 600 deg; Compatibilite de divers alliages de magnesium avec le gaz carbonique sous pression entre 400 et 600 deg

    Energy Technology Data Exchange (ETDEWEB)

    Darras, R; Baque, P; Chevilliard, C [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    'magnesium oxyde fritte'. Les echantillons, preleves dans des produits files, sont convenablement polis, deux etats de surface reproductibles etant realises a titre comparatif. Les essais ont ete effectues dans le gaz carbonique purifie, aux pressions de 25 et 60 atmospheres, et a des temperatures allant de 400 a 600, au moyen d'autoclaves speciaux en acier inoxydable, chauffes exterieurement. Leur duree est en general superieure a 1000 heures. Les equations des courbes d'augmentation de poids obtenues sont du type ({delta}p){sup n} = k.t (({delta}p en mg/cm{sup 2} et t en heures), l'exposant n etant voisin de 2, du moins jusqu'a 500 deg. C. En se referant a des resultats precedemment acquis quant a certains de ces materiaux exposes dans le gaz carbonique sous pression atmospherique et sous 15 atmospheres, il apparait que: 1) Pour un materiau determine: - a une pression donnee, l'oxydation augmente avec la temperature, - a une temperature donnee, l'oxydation augmente avec la pression, - dans les memes conditions de temperature et de pression, les resultats obtenus varient peu suivant les deux etats de surface etudies; 2) les alliages Mg-Zr presentent une resistance a l'oxydation amelioree par rapport au magnesium non allie; 3) l'alliage magnox est beaucoup moins avantageux dans le gaz carbonique que dans l'air, par rapport aux autres alliages. D'une facon generale, les courbes d'oxydation tendant vers un palier apres un certain temps d'exposition, la compatibilite de tous les alliages consideres avec le gaz carbonique apparait satisfaisante jusqu'a une temperature voisine de 500 deg. C, dans les conditions operatoires presentement definies; au dessus de 500 deg. C, des differences notables apparaissent entre les divers alliages, mais des phenomenes de sublimation interferent avec ceux d'oxydation, de sorte qu'un classement des divers materiaux ne peut etre base que sur leur resultante. (auteur)

  6. Preparation of uranium-based oxide catalysts; Preparation de catalyseurs oxydes a base d'uranium

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-07-01

    intermediaires des decompositions et indexer les raies de leurs diagrammes de diffraction X. Les oxydes issus des decompositions sont mal definis et instables: ils absorbent energiquement l'oxygene atmospherique avec modification de composition et dans certains cas de structure (oxyde pyrophorique). Afin d'obtenir des oxydes de structure stable, nous avons prepare des oxalates mixtes uranium-thorium. L'obtention d'un oxalate mixte homogene du point de vue de sa composition necessite un protocole de preparation bien defini: l'addition des solutions de nitrate de thorium et d'uranium IV a une solution d'acide oxalique maintenue a saturation. L'oxyde mixte obtenu par decomposition thermique a 500 C pendant 24 heures sous courant d'oxygene d'un oxalate U{sub x}Th{sub 1-x}(C{sub 2}O{sub 4}){sub 2}, 2 H{sub 2}O a une structure cubique bien definie dans sa masse comme en surface lorsque x ne depasse pas 0,35. Au-dela de cette concentration atomique en uranium, de l'uranium sort du reseau sous forme de UO{sub 3} ou de U{sub 3}O{sub 8} suivant la temperature. L'oxyde mixte n'est pas stoechiometrique (U{sub x}Th{sub 1-x}O{sub 2+y}) et le degre moyen d'oxydation de l'uranium varie avec la temperature et la pression partielle d'oxygene. Enfin les oxydes ont une bonne surface specifique. La mise en solution des oxalates mixtes dans une solution concentree d'oxalate d'ammonium permet le depot du catalyseur sur support, mais la difference de solubilite des oxalates de thorium et d'uranium IV dans l'oxalate d'ammonium rend impossible la preparation de sels doubles formes de thorium et d'uranium d'une part et d'ammonium d'autre part. (auteur)

  7. The Hydrographical Features of the Baltic Sea and the Disposal of Radioactive Wastes; L'Hydrographie de la Mer Baltique et l'Evacuation des Dechets Radioactifs; 0413 0418 0414 0420 041e 0413 0420 0414 ; Caracteristicas Hidrograficas del Mar Baltico en Relacion con la Evacuacion de Desechos Radiactivos

    Energy Technology Data Exchange (ETDEWEB)

    Hela, Ilmo [Institute of Marine Research Helsinki (Finland)

    1960-07-01

    'une verification approfondie au moyen d'etudes hydrographiques plus poussees, etant donne que: 1) Toute la Baltique est, en un sens, un estuaire, avec une profondeur de seuil qui ne depasse pas 18 metres dans les Detroits. 2) Le brassage y est beaucoup plus reduit que dans les oceans, pour diverses raisons: nombreuses iles, eau saumatre, stratification marquee, pratiquement pas de marees, mer partiellement recouverte de glace en hiver, peu de parcours pour les vents, faible vitesse des courants permanents. Le memoire mentionne tous ces facteurs qui diminuent la dispersion par turbulence, tant verticale qu'horizontale. Pour evaluer la dispersion par advection et par turbulence, tant dans les couches superieures qu'au fond de la mer, il faudrait faire des observations synoptiques de la vitesse des courants et de la concentration saline en un certain nombre de points' situes dans plusieurs regions de la Baltique et dans diverses conditions atmospheriques. (author) [Spanish] La memoria tiene por finalidad describir algunas caracteristicas hidrograficas del Mar Baltico que hacen que este mar, para la evacuacion de desechos radiactivos, sea diferente de las demas regiones oceanicas. Para la evacuacion de radionuclidos pueden distinguirse, en la practica, las siguientes zonas maritimas: 1) puertos; 2) vias de acceso a los puertos; 3) plataforma continental exterior, y 4) alta mar. En este sentido, no existe alta mar en el Baltico. Ademas, la validez de las normas recomendadas para estas cuatro zonas debe verificarse cuidadosamente con nuevos estudios hidrograficos, ya que: 1) Todo el Baltico es, en cierto modo, un estuario, cuya profundidad es de solo 18 metros en los estrechos daneses; 2) La velocidad de mezcla en este Mar es mucho menor que en los oceanos, pues el Baltico: tiene muchas islas; es de escasa salinidad; es muy estratificado; carece practicamente de mareas; en invierno queda parcialmente cubierto de hielo; solo registra vientos debiles; no tiene corrientes continuas mas que

  8. The radiation age of meteorites; L'age des meteorites; Opredelenie vozrasta meteoritov s pomoshch'yu radiatsii; Edad de los meteoritos

    Energy Technology Data Exchange (ETDEWEB)

    Goebel, K; Schmidlin, P [European Organisation for Nuclear Research, Geneva (Switzerland)

    1962-01-15

    de millions d'armees. Les mesures recemment effectuees au C E R N concordent en principe avec les resultats auxquels ont abouti d'autres auteurs. Le memoire traite des erreurs probables qui peuvent resulter des pertes de gaz par diffusion, et de la protection dont la meteorite beneficie dans la preatmosphere. E n tenant compte de la section efficace pour la production de tritium dans les elements qui constituent la meteorite, on peut determiner les valeurs du flux des rayons cosmiques dans l'espace extra-atmospherique. (author) [Spanish] Los radioisotopos formados por la accion de los rayos cosmicos sobre los meteoritos durante el recorrido de estos a traves del espacio pueden utilizarse para reconstruir el historial de estos cuerpos. Para evaluar el tiempo durante el cual el meteorito estuvo expuesto a los rayos cosmicos, es preciso determinar cuantitativamente los radioisotopos y los elementos descendientes que se han acumulado en el mismo. (A fin de poder efectuar el calculo, hay que suponer que el flujo de rayos cosmicos ha permanecido constante en el tiempo.) Estas mediciones se basan con frecuencia en los isotopos gaseosos, y a que estos pueden separase con facilidad del resto de la materia meteoritica. E n los trabajos objeto de este informe, se han empleado principalmente el tritio y el argon. A partir de la razon {sup 3}H/{sup 3}He se han podido calcular edades que abarcan de algunos millones a varios cientos do millones de anos. Las mediciones recientemente efectuadas en el CERN concuerdan esencialmente con los resultados obtenidos por otros investigadores. Los autores discutiran los errores probables debidos a las perdidas de gases por difusion, asi como el efecto de blindaje del meteorito en su recorrido preatmosferico. Si se tienen en cuenta los valores medidos de la seccion eficaz para la produccion de tritio a partir de los elementos de que se compone el meteorito, es posible determinar el flujo de rayos cosmicos en el espacio sideral. (author

  9. Containment for Heavy-Water Gas-Cooled Reactors; Le Confinement des Reacteurs a Eau Lourde Refroidis par Gaz

    Energy Technology Data Exchange (ETDEWEB)

    Verstraete, P.; Lehmann, D.; Lafitte, R. [Bonard et Gardel, Ingenieurs-Conseils, Lausanne (Switzerland)

    1967-09-15

    par gaz sont passes en revue dans le but d'etablir les specifications des enceintes de confinement en fonction des conditions des sites disponibles en Suisse pour la construction de centrales nucleaires. Ces specifications sont etablies d'apres les taux de dose consideres comme admissibles pour les populations vivant aux environs de la centrale en cas d 'accident grave du reacteur, en se basant sur des conditions meteorologiques et demographiques representatives de la plupart des sites du pays. Differents modes de construction de l ' enceinte de confinement, prenant en consideration les conditions qui s'etablissent dans l'enceinte a la suite de l'accident maximal concevable du reacteur, sont consideres. Les enceintes etudiees sont les suivantes: beton precontraint; beton precontraint avec coupole d'acier; beton precontraint avec peau d' etancheite interieure en acier; acier avec ecran lateral en beton pour la protection contre les radiations; et double confinement. Le degre d'etancheite des enceintes etudiees a ete considere comme une caracteristique lie e au mode de construction particulier et non comme une valeur prescrite en vue de laquelle la construction devait etre adaptee. Les caracteristiques d'etancheite de chaque enceinte sont estimees et les prix de chaque construction ont ete determines sur la base de plans precis avec le concours de diverses entrepises specialisees. L'estimation de l'efficacite des differentes enceintes, sous l'an gle de la securite, a ete faite en prenant en consideration differentes procedures en cas d' accident parmi lesquelles on citera principalement le rejet atmospherique, au travers de filtres adequats, et la decontamination de l 'atmosphere de l 'enceinte par recyclage dans des batteries de filtres. Une dizaine de cas, correspondant a differentes combinaisons de modes de construction et procedures en cas d'accident, font l 'objet d'une comparaison tres detaillee qui a ete realisee grace a un programme pour ordinateur electronique

  10. Health physics problems in the context of the development of industrial uses of nuclear energy; Les problemes de radioprotection devant le developpement de l'utilisation industrielle de l'energie nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Duhamel, F; Menoux, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    surete des sites permettent de preciser les parametres de diffusion ou de reconcentration dans les divers milieux naturels de facon a permettre de prevoir le sort des effluents radioactifs depuis les installations qui en sont la source jusqu'a l'homme qui peut y etre expose. L'organisation de la surveillance de la radioactivite sur les sites nucleaires est liee tres etroitement aux etudes de surete. Parmi les nombreuses etudes a mener, on insistera plus particulierement sur les experiences de diffusion atmospherique dont le but est de preciser la valeur des parametres introduits par la theorie tout en permettant de tenir compte de facteurs complementaires. - les etudes hydrologiques, hydrogeologiques et oceanographiques, qui permettent de preciser le sort des ions radioactifs dans l'hydrosphere. - les experiences et etudes liees aux possibilites de rejet ou de stockage des dechets dans le sol. L'ensemble de ces travaux constitue un moyen complementaire, la radioprotection, qui etablit une liaison necessaire entre la surete nucleaire proprement dite laquelle concerne le fonctionnement meme des installations nucleaires, et la surveillance medicale laquelle concerne directement la sante de l'individu et de la population. En meme temps,la radioprotection donne a chacune de ces disciplines une independance qui accroit leur efficacite sur le plan de la securite. (auteurs)

  11. Preparation of uranium-based oxide catalysts; Preparation de catalyseurs oxydes a base d'uranium

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-07-01

    et indexer les raies de leurs diagrammes de diffraction X. Les oxydes issus des decompositions sont mal definis et instables: ils absorbent energiquement l'oxygene atmospherique avec modification de composition et dans certains cas de structure (oxyde pyrophorique). Afin d'obtenir des oxydes de structure stable, nous avons prepare des oxalates mixtes uranium-thorium. L'obtention d'un oxalate mixte homogene du point de vue de sa composition necessite un protocole de preparation bien defini: l'addition des solutions de nitrate de thorium et d'uranium IV a une solution d'acide oxalique maintenue a saturation. L'oxyde mixte obtenu par decomposition thermique a 500 C pendant 24 heures sous courant d'oxygene d'un oxalate U{sub x}Th{sub 1-x}(C{sub 2}O{sub 4}){sub 2}, 2 H{sub 2}O a une structure cubique bien definie dans sa masse comme en surface lorsque x ne depasse pas 0,35. Au-dela de cette concentration atomique en uranium, de l'uranium sort du reseau sous forme de UO{sub 3} ou de U{sub 3}O{sub 8} suivant la temperature. L'oxyde mixte n'est pas stoechiometrique (U{sub x}Th{sub 1-x}O{sub 2+y}) et le degre moyen d'oxydation de l'uranium varie avec la temperature et la pression partielle d'oxygene. Enfin les oxydes ont une bonne surface specifique. La mise en solution des oxalates mixtes dans une solution concentree d'oxalate d'ammonium permet le depot du catalyseur sur support, mais la difference de solubilite des oxalates de thorium et d'uranium IV dans l'oxalate d'ammonium rend impossible la preparation de sels doubles formes de thorium et d'uranium d'une part et d'ammonium d'autre part. (auteur)

  12. Electrical characteristics of sphere-plane type spark counters; Caracteristiques electriques de compteurs a etincelles du type sphere-plan; Ehlektricheskie kharakteristiki iskrovykh schetchikov tipa shar-ploskost'; Caracteristicas electricas de los contadores de chispas del tipo esfera-plano

    Energy Technology Data Exchange (ETDEWEB)

    Laborie, P; Blanc, D [Centre de Physique Nucleaire, Faculte des Sciences de Toulouse (France)

    1962-04-15

    The authors describe here the mechanical construction and operating characteristics of spark detectors using a small (0.30 mm) diameter sphere as anode, set opposite to a plane cathode and working by the ''corona'' effect, in air at atmospheric pressure. Counting characteristics are very similar to those of Rosenblum-type anode wire detectors. However, the sphere counter has a certain superiority over the Rosenblum counter inherent in its geometry : (a) there sidual current (background) is low and the release of ozone and nitrous oxides during the spark is not of great significance; (b) its self-capacity being very small, the detector gives a faster response; (c) unlike in the case of wire counters, efficiency is independent of particle incidence direction; (d) its sensitive volume, that of a solid of revolution around the axis of symmetry of the detector, amounts to a few cubic millimetres and, being very clearly defined, permits realization of accurate telescopic devices. (author) [French] Les auteurs decrivent la realisation mecanique et les caracteristiques de fonctionnement de detecteurs a etincelles utilisant comme anode une sphere de petit diametre (0,30 mm), disposee en regard d'une cathode plane, et fonctionnant en regime d'effet , dans l'air sous la pression atmospherique. Les caracteristiques de comptage sont voisines de celles des detecteurs a fil anodique, du type Rosenblum. Le compteur a sphere presente cependant sur le compteur de Rosenblum un certain nombre d'avantages lies a sa geometrie: a) le courant residuel (bruit de fond) est faible, et le degagement d'ozone et d'oxydes de l'azote lors des etincelles est peu considerable; b) sa capacite propre etant tres petite, le detecteur presente une reponse plus rapide; c) l'efficacite est independante de la direction d'incidence de la particule, contrairement a ce qui a lieu pour les compteurs a fil; d) le volume sensible de revolution autour de l'axe de symetrie du detecteur, qui est de

  13. Preparation of plutonium hexafluoride. Recovery of plutonium from waste dross (1962); Preparation de l'hexafluorure de plutonium. Recuperation du plutonium des scories d'elaboration (1962)

    Energy Technology Data Exchange (ETDEWEB)

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

    1962-07-01

    facteurs physiques sur la vitesse de fluoration du tetrafluorure de plutonium solide par le fluor. Dans un appareil a four horizontal et circulation de fluor a la pression atmospherique de 520 deg. C, avec un debit de fluor pur de 9 l.h{sup -1}, il est possible de transformer une charge de 3 g de tetrafluorure en hexafluorure avec un taux de transformation d'environ 100 pour cent et un rendement de recuperation superieur a 90 pour cent, en 4 a 5 h. La vitesse de fluoration est fonction de la temperature du debit de fluor, de la surface de la nacelle, de l'epaisseur de la couche de tetrafluorure et du temps de reaction. Elle ne depend pas de la diffusion du fluor dans le Solide mais est commandee par la reaction a l'interface gaz-solide et suit la loi cinetique (1 - T{sub T}){sup 1/3} = kt + 1. L'existence de fluorures intermediaires, en particulier Pu{sub 4} F{sub 17}, est confirmee par une cassure de la droite d'Arrhenius vers 370 deg. C, par des differences dans les vitesses de fluoration au sein de la couche de tetrafluorure et par des variations reversibles de coloration. La transformation en hexafluorure s'accompagne d'une purification vis-a-vis des elements etrangers entrant dans la composition de plutonium initial. Recuperation du plutonium des scories d'elaboration: L'etude est basee sur la transformation en hexafluorure gazeux des grains de plutonium occlus dans les scories d'elaboration, cet hexafluorure devant fournir par decomposition thermique un tetrafluorure directement recyclable au stade elaboration. - Dans les conditions envisagees, ce procede n'est pas utilisable industriellement. Apres broyage, une Reparation par milieu dense (iodure de methylene) permet de separer une scorie enrichie en plutonium (75 pour cent du Pu dans 2,6 pour cent du poids des scories) et une scorie pauvre. Par fluoration prolongee (16 h) des diverses portions recueillies, il est possible de recuperer environ 80 pour cent du plutonium. Un appareillage de traitement base sur la

  14. Osservazioni in margine sulla musica per l’immacolato concepimento della Vergine, al tempo di Sisto IV

    Directory of Open Access Journals (Sweden)

    Camilla Cavicchi

    2012-05-01

    , legata alla devozione dell’immagine dell’Immacolata. Le immagini furono, in effetti, uno strumento di particolare importanza nella strategia del pontefice. In esse la musica entrò dapprima con l’evocazione delle antifone e della preghiera, citate nei cartigli e nei bordi dei dipinti, poi attraverso la figura di re David (rappresentante della stirpe di Maria, nelle danze di angeli e, infine, con l’adozione di alcuni elementi iconografici propri dell’Assunzione. A partire dal primo quarto del Cinquecento l’iconografia dell’Immacolata s’arricchì dell’immagine degli angeli musicanti, evocazione certamente dell’armonia celeste, ma anche testimoni della pratica musicale legata alla devozione dell’Immacolato concepimento della Vergine.The introduction of the celebration of the Immaculate Conception prompted a series of innovations in liturgical music that changed the foundations of music and developed the figurative theme of the Virgin Mary.One of the first official actions of Pope Sixtus IV was to commission a new Office from Leonardo Nogarolo (1477, the Officium Immaculatae Virginis Mariae, and later the Officium Conceptionis Virginis Mariae by Bernardino Busti (1492, which both reached us without notation. Music for the Proper of the mass and for the Office by L. Nogarolo and the Introit of the mass Egredimini et videte filie Sion was composed and published, separately, in two collections by Francesco de Brugis: Antiphonarium and Graduale secundum morem sancte Romanae ecclesie (Venice, Lucantonio Giunta, 1503 and 1500. During the papacy of Sixtus IV, chants were undoubtedly inspired by the Office by L. Nogarolo, but it is also possible that several musical traditions coexisted during the first years after the establishment of the celebration. Records confirm that Sixtus IV used to celebrate this occasion in St. Peter’s Basilica, reciting the Office followed by the mass in the morning and, in the afternoon, leading a procession to the church of

  15. El zorro del cielo: un mito sobre el origen de las plantas cultivadas y los intercambios con el mundo sobrenatural

    Directory of Open Access Journals (Sweden)

    1997-01-01

    Full Text Available LE RENARD CELESTE : UN MYTHE SUR L’ORIGINE DES PLANTES CULTIVEES ET LES ECHANGES AVEC LE MONDE SURNATUREL. Cet article propose une interprétation d’un mythe andin relatant le voyage de l’ancêtre des renards au ciel. Dans le sud du Pérou et en Bolivie, ce mythe explique, selon les versions, l’origine des plantes cultivées ou celle des renards. À partir d’une analyse séquentielle qui s’efforce de déchiffrer le symbolisme du récit, nous montrons que ce mythe constitue une réflexion des pasteurs de la puna sur leurs relations saisonnières avec les populations des vallées, en particulier à partir du mois d’avril, lorsqu’ils descendent prêter leur force de travail aux agriculteurs céréaliers. Le mythe présente la complémentarité entre les deux étages écologiques comme analogue à celle qui s’établit entre les hommes et le monde surnaturel. Ces deux complémentarités, qui sont étroitement solidaires, apparaissent à leur tour comme la condition de la fécondité agricole. Nous menons notre analyse à partir de deux versions quechuas que nous avons recueillies dans la province de Quispicanchis (dept. de Cuzco, Pérou et dont nous présentons une transcription et une traduction en appendice. Este artículo propone una interpretación de un mito andino que relata el viaje del ancestro de los zorros al cielo. En el sur del Perú y en Bolivia, ese relato explica, según las versiones, el origen de las plantas cultivadas o de los zorros. A partir de un análisis secuencial que ensaya descifrar el simbolismo de los hechos narrados, mostramos que el mito constituye una reflexión de los pastores de la puna sobre sus relaciones estacionales con las poblaciones de los valles, en particular a partir del mes de abril, cuando ellos descienden a prestar su fuerza de trabajo a los cultivadores de cereales. El mito presenta la complementariedad entre los dos pisos ecológicos como análoga a la que se establece entre los hombres y el

  16. Problems related with the power regulation of reactors by physico-chemical methods, and the behaviour of water and heavy water in nuclear reactors; Comportement de l'eau et de l'eau lourde dans les reacteurs nucleaires et problemes de la regulation de puissance par voie physico-chimique

    Energy Technology Data Exchange (ETDEWEB)

    Dolle, L; Conan, D; Dirian, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    . Comportement de l'eau lourde dans les reacteurs en exploitation. Pollution isotopique de l'eau lourde: Sa vitesse est liee au type de reacteur et a certains incidents caracteristiques. L'utilisation d'une colonne de reconcentration est un moyen efficace pour maintenir le titre de l'eau lourde dans un reacteur dont la pollution isotopique lente ne peut etre exclue. Detection des fuites d'eau lourde: Elle permet de mesurer les taux instantanes de fuites faibles, de localiser la fuite, et de controler la contamination atmospherique dans l'enceinte du reacteur. On procede par analyse isotopique du deuterium ou par dosage du tritium sur des echantillons d'eau de condensation. Pollution chimique et epuration de l'eau lourde: La pollution chimique de l'eau lourde constitue un des problemes les plus complexes de la chimie des reacteurs. La corrosion des materiaux constituant le coeur et le circuit d'eau lourde varie dans de larges limites avec l'etat de purete de l'eau lourde, les performances des circuits d'epuration et des mesures directes permettent d'en apprecier l'importance. Les connaissances acquises permettent de degager des normes de purete dont l'observation est susceptible de garantir un fonctionnement satisfaisant du reacteur. 4) Decomposition radiolytique de l'eau lourde: Une meilleure connaissance de son allure quantitative dans les reacteurs est necessaire pour prevoir les degagements de gaz tonnant dans les reacteurs de puissance. Le taux de radiolyse evolue avec la purete chimique de l'eau et la puissance instantanee du reacteur. L'experience des reacteurs a eau lourde du CE.A. et l'etude systematique de la decomposition radiolytique de l'eau dans le coeur des piles piscines sont exposees Mise en oeuvre du controle de la reactivite par voie physico-chimique. Controle de la reactivite par empoisonnement homogene du moderateur: Une comparaison de l'evolution de l'empoisonnement Xenon avec l'antireactivite residuelle du poison en solution pendant sa consommation

  17. Recent progress in the detection of bursts in the canning in French reactors; Progres recents de la detection des ruptures de gaines dans les reacteurs francais G1, EL2, G3, EL3

    Energy Technology Data Exchange (ETDEWEB)

    Goupil, J; Grenon, M; Raffailhac, J; Roguin, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1959-07-01

    des produits de fission, 2) de la pollution d'uranium des gaines et de la pollution eventuelle des canaux apres ruptures de gaines rapides. L'evolumetre est constitue par une memoire qui stocke les valeurs de l'activite des canaux prises a un instant considere comme reference. A cette memoire, on vient comparer les valeurs de l'activite des canaux en cours de prospection. Une difference entre ces valeurs indique l'apparition ou l'evolution d'une fissure de gaine. Pour tenir compte des variations du regime thermodynamique dans les canaux, les valeurs extraites de la memoire sont corrigees par un signal provenant d'un detecteur d'activite place dans le circuit general de sortie du gaz de la pile. Dans le cas de la pile EL{sub 2}, egalement a refroidissement par CO{sub 2}, sous pression, une methode analogue a celle de G{sub 3} a ete utilisee. Des echantillons de gaz de refroidissement sont preleves dans chacune des 133 cellules de la pile successivement par l'ouverture d'electrovannes. Le gaz est filtre et les produits de fission sont extraits par une methode de collection electrostatique. Un scintillateur et une chaine electronique fournissent un signal specifique des produits de fission qui s'inscrit sur un enregistreur. Dans le cas d'un depassement du seuil d'activite, la cellule incriminee est isolee du systeme de prospection et prise en charge par un detecteur 'suiveur' qui permet de suivre l'evolution de la fissure. Une annee d'exploitation de la pile G1 qui est refroidie a l'air a la pression atmospherique a permis d'obtenir des resultats sur le fonctionnement du dispositif D.R.G. ce qui nous a amenes a perfectionner le dispositif initial en installant un evolumetre du type decrit ci-dessus pour G{sub 3}. Le reacteur EL{sub 3}, refroidi a l'eau lourde, utilise un systeme de detection base sur la mesure, au moyen de compteurs G.M., de l'activite des gaz de fission entraines par de l'helium dilue dans l'eau lourde puis extraits de celle-ci par des hydrocyclones. La

  18. Effects of Temperature and Pressure on Hot-Atom Reactions in Bromoethane; Effets de la Temperature et de la Pression sur les Reactions des Atomes Chauds dans le Bromoethane; Vliyanie temperatury i davleniya na reaktsii goryachikh atomov v bromehtane; Efectos de la Temperatura y de la Presion en las Reacciones de Atomos Calientes en el Bromoetano

    Energy Technology Data Exchange (ETDEWEB)

    Cole, A. J.; Mia, M. D.; Miller, G. E.; Shaw, P. F.D. [Nuclear Physics Laboratory, Oxford University, Oxford (United Kingdom)

    1965-04-15

    -Sign et -115 Degree-Sign C et a la pression atmospherique, ainsi qu'a la temperature de 18 Degree-Sign C et a des pressions allant jusqu'a 10{sup 4} atm. En plus des composes deja signales, ils ont trouve de faibles quantites de bromoethylene, de dibromo- 1,2-ethylene, de mono-et dibromopropanes et de mono-, di-, tri-et tetrabromobutanes; il existe en outre des indices indirects de la formation de bromobutenes. Les reactions qui dependent de la diffusion sont complexes-, on peut les expliquer en admettant qu'une pyrolyse du liquide se produit dans le voisinage de l'atome chaud et donne des radicaux bromoethyle et de l'ethylene. C'est alors a l'addition de radicaux a l'ethylene que sont dus a la fois la formation de bromures contenant plus de deux atomes de carbone et les rendements en ces bromures, qui dependent de la diffusion. D'une maniere generale, une reduction de la temperature ou un accroissement de la pression entraine une augmentation du rendement imputable a une diminution de la vitesse de diffusion. L'effet est le plus marque sur le rendement en dibromo-1, 2-ethanef qui se produit surtout par la reaction de diffusion des radicaux bromoethyle et qui est quadruple par l'application de 10{sup 4} atm du fait de la suppression de la dissociation CH{sub 2}-CH{sub 2}Br Rightwards-Arrow-Over-Leftwards-Arrow CH{sub 2} = CH{sub 2} + Br En revanche, la dissociation du radical (CH{sub 3} -CHBr) en bromoethylene et hydrogene (CH{sub 2} = CHBr + H) est impossible, et le rendement en dibromo-1,1-ethane est a peu pres independant de la pression. La variation, en fonction de la temperature et de la pression, du rendement en bromoethane pour de fortes concentrations de brome est voisine de celle qui avait ete prevue precedemment par l'un des auteurs. (author) [Spanish] Se ha estudiado el rendimiento de los compuestos que contienen {sup 80m}Br, producidos por irradiacion de mezclas de bromoetano y bromo con neutrones de 14 MeV a 18 Degree-Sign C, -80 Degree-Sign C y -115 Degree

  19. Intensificación de la circulación atmosférica meridional en la región subtropical de América del sur inferida a partir de registros dendroclimatológicos

    Directory of Open Access Journals (Sweden)

    1998-01-01

    Full Text Available RENFORCEMENT DE LA CIRCULATION ATMOSPHERIQUE MERIDIONALE D’AMERIQUE DU SUD DEDUITE DE DONNEES DENDROCLIMATOLOGIQUES. L’objectif principal de cette étude est de montrer comment on peut utiliser la dendroclimatologie pour caractériser les variations climatiques qui ont affecté ces deux derniers siècles la région subtropicale de montagne de l’Amérique du Sud. Nous avons utilisé des chroniques de largeur d’anneaux de croissance obtenues sur du nogal criollo (Juglans australis et du Cèdre Tumaco (Cedrela lilloi pour estimer les variations mensuelles de température et de précipitation depuis 1800. Comme les mesures météorologiques directes, les séries dendroclimatologiques sensibles aux précipitations montrent un accroissement soutenu des précipitations dans la région montagneuse subtropicale qui démarre vers 1950, que l’on n’avait pas du tout observé au cours des 200 années précédentes. Le gradient de pression atmosphérique entre les régions tropicales et subtropicales mesuré par les différences de pression entre Cuiaba (15°S et Reconquista (29°S s’est accru progressivement depuis 1950. Ce renforcement du gradient de pression, associé à une augmentation des températures dans les zones subtropicales paraît avoir induit un déplacement vers le sud de la cellule continentale de basse pression sur l’Amérique du Sud. Ce déplacement pourrait avoir provoqué une augmentation des précipitations et une réduction de la durée de la saison sèche dans le subtropique montagneux. Les corrélations spatiales entre l’épaisseur des anneaux de croissance et la Température de Surface de l’Océan (SST indiquent également que l’augmentation des précipitations subtropicales pourrait aussi être reliée à une augmentation significative de la SST de l’Atlantique sud survenue au cours des 4 dernières décades. Ces résultats montrent de manière claire le potentiel des méthodes dendroclimatologiques pour reconstituer les

  20. Radiation Synthesis of Stannous Dibromodibutyl; Synthese radiochimique de l'etain dibromopibutyle; Radiatsionno-khimicheskij sintez dibromdibutilolova; Sintesis radioquimica del dffiromodibutilestano

    Energy Technology Data Exchange (ETDEWEB)

    Abramova, L. V.; Vereshchinskij, I. V.; Kocheshkov, K. A.; Miretskij, V. Yu.; Pozdneev, V. V.; Ryabukhin, Yu. S.; Sheverdina, N. I.

    1963-11-15

    uninterrupted process. A reaction mechanism is proposed to explain the principles of the process which give a substantial irradiation yield. (author) [French] Le fait qu'il est, en principe, possible de realiser la synthese de composes organiques de l'etain en soumettant un melange d'etain metallique et d'halogenures appropries a l'action des rayons gamma du {sup 60}Co a ete etabli pour la premiere fois par Abramova, Kotchechkov et Cheverdina en 1958. Les conditions des experiences, qui etaient executees a l'aide d'un appareillage en vene depourvu de melangeur, ne permettait pas de determiner les lois cinetiques qui president a la formation des composes organometalliques de cette categorie. L'etude consideree a ete entreprise pour elucider l'influence qu'exercent plusieurs facteurs sur la vitesse a laquelle se produit la synthese radiochimique des composes organiques de l'etain, en prenant comme exemple l'etain dibromodibutyle. A cette fin, les auteurs ont concu et construit une installation speciale assurant le chargement periodique des composants et l'evacuation des produits de la reaction. Cette installation permettait de maintenir une temperature constante, d'assurer une agitation efficace et de prelever periodiquement des echantillons aux fins d'analyse. Son element essentiel - un recipient en acier inoxydable d'une contenance de deux litres ou se produisait la reaction - etait equipe d'un melangeur. Elle comprenait une source de rayons y{gamma} au {sup 60}Co. Les experiences ont eu lieu a une temperature de 80 {+-} 5{sup o}C, sous pression atmospherique. Le debit de dose, mesure a l'aide d'un dosimetre au sulfate ferreux, etait d'environ 50 rad/s. On a utilise de la poudre d'etain metallique et du bromure de butyle de puretes differentes. Les substances entrant dans la reaction ont ete employees en proportions diverses. On a constate qu'il se produisait, dans ces conditions, une reaction radiochimique orientee au cours de laquelle se formait essentiellement de l

  1. Uranium Ore and Concentrate Sampling; Echantillonnage des Minerais et des Concentres d'Uranium; Otbor prob uranovoj rudy i kontsentratov; Muestreo de Minerales y Concentrados de Uranio

    Energy Technology Data Exchange (ETDEWEB)

    McGinley, F. E.; Brown, D. L.; Langridge, R. W. [United States Atomic Energy Commission, Grand Junction, CO (United States)

    1966-02-15

    dirigees par des exploitants sous contrat. Un lot moyen comprend environ 50 futs (de 210 litres) et pese environ 16 tonnes. Comme les caracteristiques physiques et chimiques de ces concentres varient considerablement d'un fut a l'autre, il est necessaire d'echantillonner chaque fut. Au cours de ces annees, on a eu recours a differents procedes d'echantillonnage - tubes, sondes ouvertes, sondes fermees ou ecoulement du minerai. Ce dernier procede est le plus precis a condition que l'on prenne les precautions requises pour prevenir les changements de poids resultant de l'exposition a l'atmosphere. Comme les concentres ont tendance a absorber l'humidite ambiante ou a perdre leur humidite selon les conditions atmospheriques auxquelles ils sont exposes, on a constamment mis au point des methodes speciales de sous-echantillonnage, de sechage et de preparation des echantillons en vue de rendre l'echantillonnage de tous les lots plus exact et plus precis. On a eu beaucoup recours a la statistique pour analyser et interpreter les mesures et les donnees pour l'evaluation des echantillonnages. (author) [Spanish] La oficina de Grand Junction de la Comision de Energia Atomica de los Estados Unidos ha tenido que adquirir grandes cantidades de uranio natural, tanto en forma de mineral como en forma de concentrado. Las tecnicas empleadas para el muestreo de minerales difieren necesariamente de las empleadas para los concentrados. Los autores de la memoria analizan las operaciones que integran los sistemas generales de medicion y muestreo de minerales y concentrados, prestando atencion especial a la exactitud y precision de cada una de ellas. Entre 1948 y 1964 se sacaron muestras de 58 millones de toneladas de mineral en unas 40 plantas de muestreo mecanico situadas en la parte occidental de los Estados Unidos. En todas estas plantas el mineral fue pesado, muestreado y analizado segun practicas aprobadas por la AEC de los Estados Unidos. Para las muestras se siguieron los principios

  2. Latitudinal effect in the transport of radiocarbon from stratosphere to troposphere; Eflet de la latitude sur le transport du radiocarbone de la stratosphere a la troposphere; Vliyanie geograficheskoj shiroty na peremeshchenie radioaktivnogo ugleroda iz stratosfery v troposferu; Efecto de la latitud sobre el transporte del carbono radiactivo de la estratosfera a la troposfera

    Energy Technology Data Exchange (ETDEWEB)

    Tauber, Henrik [Carbon-14 Dating Laboratory, Dept. of Natural Sciences, National Museum, Copenhagen (Denmark)

    1962-01-15

    les temps de melange a l'interieur de la stratosphere et de la troposphere. A cet effet, on mesure le taux d'accroissement de la teneur en carbone-14 du CO{sub 2} atmospherique et de certains vegetaux. Ces donnees sont actuellement recueillies dans de nombreuses localites differentes. Il ressort des mesures effectuees au Danemark sur des cereales qu'en 1958 et 1959 la teneur en carbone-14 de ces cereales y accusait une augmentation superieure de plusieurs centiemes a l'augmentation moyenne pour l'hemisphere nord. Au cours de l'ete 1959, la teneur en carbone-14 etait superieure de 33% au niveau de 1954. Les accroissements considerables ainsi intervenus en 1958 et 1959 sont sans doute un phenomene parallele aux , printanieres des retombees de strontium-90, enregistrees au cours de ces memes annees dans la zone temperee boreale. Ayant ainsi constate que la teneur en carbone-14 des cereales danoises est superieure a la moyenne relevee pour l'hemisphere, on peut supposer que la contamination par le carbone-14 varie selon la latitude. Cela concorde avec les observations faites au sujet de la retombee de particules qui descendent de la stratosphere par un mecanisme circulatoire analogue. Des effets latitudinaux de cette importance permettent de determiner les voies empruntees par le CO{sub 2} entre la stratosphere et la troposphere, en mesurant directement la radioactivite du carbone-14 que contient le CO{sub 2} tropospherique recueilli par un certain nombre de stations d'echantillonnage disseminees. L'auteur evalue l'ordre de grandeur de l'effet possible de la latitude lors de l'etat stable avant la bombe. Cet effet peut expliquer en partie les variations a court terme de l'activite du carbone-14, constatees dans les cercles annuels des arbres au cours des 1300 dernieres annees. (author) [Spanish] La gran cantidad de carbono-14 (aproximadamente 3 Mc) que las explosiones atomicas han liberado, principalmente en la estratosfera, permite estudiar los caminos seguidos

  3. Motion of Plasmoid in a Curvilinear Magnetic Field; Mouvement d'un Plasmoide dans un Champ Magnetique Curviligne; Dvizhenie plazmennogo sgustka v krivolinejnom magnitnom pole; Movimiento de un Plasmoide en un Campo Magnetico Curvilineo

    Energy Technology Data Exchange (ETDEWEB)

    Vojcenja, V. S.; Gorbanjuk, A. G.; Onishhenko, I. N.; Safronov, B. G.; Hizhnjak, N. A.; Shkoda, V. V. [Fiziko-Tehnicheskij Institut, AN USSR, Khar' kov, USSR (Ukraine)

    1966-04-15

    'empechent pas la derive des ions lourds vers; les parois de la chambre. Meme dans les plasmas denses ou 4{pi}n{sub 0}Mc{sup 2}/H{sup 2}{sub 0} >> 1, la derive des ions lourds est soumise aux memes lois que dans l'approximation a une seule particule. Une analyse plus precise de la structure des champs montre qu'en plus du champ de polarisation perpendiculaire au plan du tore, il existe un champ electrique radial dirige vers la paroi interne de la chambre torique. La grandeur du champ de polarisation est determinee essentiellement par des 'courants de raccourcissement ' et, par consequent, la mesure des champs de polarisation confirme indirectement l'hypothese de l'existence de ces champs. Des experiences anterieures oni montre que l'ordre de grandeur des champs de polarisation mesures est en bon accord avec celui des valeurs prevues. Dans le present memoire les auteurs etudient les resultats de la recherche experimentale sur le passage et la decontamination de plasmoiedes rapides a densite elevee (n{sub 0} > 10{sup 13} cm{sup -3}, 4{pi}n{sub 0}Mc{sup 2}/H{sup 2}{sub 0} Asymptotically-Equal-To 5 x 10{sup 3} >> 1). Pour obtenir les plasmoiedes, les auteurs ont utilise une source coaxiale avec admission de gaz puise (1 cm3 d'hydrogene a la pression atmospherique). La batterie source, d'une capacite de 17 {mu}F, etait chargee a 18 kV. Apres le passage a travers la section rectiligne du champ magnetique (L = 150 cm) le plasma est entre dans le champ magnetique torique (rayon de courbure, 75 cm, angle de deflection, environ 90 Degree-Sign ). L'intensite du champ magnetique puise a atteint 10 kOe et est restee pratiquement inchangee pendant le passage du plasma (T = 10 ms). Pour l'utilisation des plasmoiedes on a eu recours a un spectrographe de masse de Thompson, a un analyseur de masse de transit, a des sondes electriques et de haute frequence, a des calorimetres et a un plasmoscope. A l'entree dans le solenoiede torique la vitesse des fronts de plasma de densite n{sub 1} Tilde

  4. Detailed design of a fixed filter-paper alpha-air-monitor with less than 15-min response time; Detecteur d'aerosols contenant des emetteurs alpha, muni d'un papier filtre fixe, a temps de reponse inferieur a quinze minutes; Podrobnaya konstruktsiya vozdushnogo registratora al'fa-chastits s fiksirovannym bumazhnym fil'trom so vremenem srabatyvaniya menee pyatnadtsati minut; Monitor de hoja de papel filtro fija para emisores alfa suspendidos en el aire, cuyo tiempo de reaccion es inferior a 15 minutos

    Energy Technology Data Exchange (ETDEWEB)

    Gentry, W O; Seaborn, G B [Oak Ridge Gaseous Diffusion Plant, Oak Ridge, TN (United States)

    1962-04-15

    peut s'attendre du fait des variations diurnes de la radioactivite atmospherique. Le prototype de l'appareil comprend une pompe a vide qui aspire l'air pour le faire passer a travers un disque de papier filtre sur lequel se deposent les aerosols. Le rayonnement alpha emis par les aerosols est decele au moyen d'un scintillateur. Le montage electronique comprend des amplificateurs et des circuits de debitmetres et fournit des donnees proportionnelles au niveau de la radioactivite et a la vitesse des variations de ce niveau. L'un des circuits comprend un condensateur electrolytique a tres haute capacite qui a ete soumis a des essais prolonges pour s'assurer que certaines conditions de fuite peuvent etre remplies. En outre, il a fallu veiller tout particulierement a ce que des fluctuations statistiques ne suffisent pas pour declencher l'avertisseur. Douze transistors ont ete utilises dans le circuit. Ce detecteur est moins encombrant et plus simple que le paragraph autres types connus. Il peut etre fabrique a meilleur compte et son fonctionnement et son entretien sont plus economiques. Il declenche l'avertisseur quinze minutes apres que les concentrations d'aerosols d'uranium ont depasse 2,1 {center_dot} 10{sup -10} {mu}c/cm{sup 3} (soit trois fois et demie la concentration maximum admissible pour une exposition de 40 heures par semaine). Il peut aussi servir a mesurer la concentration hebdomadaire moyenne d'aerosols d'uranium. A cet effet, on enleve le disque en papier filtre dont on mesure la radioactivite apres une certaine periode de decroissance. (author) [Spanish] El polvo de uranio, emisor alfa, que se halla en suspension en el aire plantea el principal problema de higiene radiofisica en las instalaciones de difusion gaseosa destinadas a la separacion isotopica del uranio. Desde hace varios anos se esta ejectuando en la instalacion de difusion gaseosa de Oak Ridge un programa de perfeccionamiento de los instrumentos para la deteccion de este polvo. La presente

  5. Contribution to a research on electron beam welding of metals; Contribution a l'etude de la soudure des metaux par faisceau d'electrons

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-03-15

    les qualites metallurgiques des ensembles soudes. Cette etude a amene a definir un canon a electrons aussi adapte que possible a la realisation de soudures, tant au point de vue comportement, notamment lors des passages de la pression atmospherique a la pression reduite de 10{sup -5} Torr necessaire pour la realisation de la soudure, qu'au point de vue de la facilite du reglage des divers parametres de soudure necessaire pour l'etude envisagee. La variation des parametres de soudure montre que la forme de la zone fondue, passe du segment de cercle a celle d'un triangle a grand elancement. Ce qui implique un changement continu du mode de transmission de chaleur. Des essais ont ete realises pour confirmer cette maniere de voir, notamment l'obtention, des isothermes en regime dynamique et la comparaison de ces isothermes avec celles relevees en utilisant le procede de soudure par argon arc. Le bilan thermique de l'energie fournie a la piece, de l'energie necessaire a la fusion et de l'energie perdue (conduction, rayonnment, vaporisation) a ete etabli. Ces resultats mettent en evidence que la quasi totalite de l'energie est utilisee pour la fusion, que les diverses pertes sont negligeables et que la transmission de la chaleur ne peut s'etablir par conduction dans la piece pendant le temps 'soudure' lorsqu'on opere dans des conditions de regime telles que la zone fondue presente une section faible, caracteristique essentielle du procede. Ces essais confirment egalement que la cavite creusee par le faisceau d'electrons est libre de metal fondu, ce qui permet le passage des electrons dont la penetration dans la matiere est negligeable. Cette maniere de voir est confirmee par des macrographies sur pieces fixes sur lesquelles ont ete executes des points de soudure tres courts: ces macrographies montrent l'existence d'un canal central. Les essais effectues en regime dynamique confirment egalement l'existence de ce canal, lorsque en cours de soudure on interrompt brutalement le