WorldWideScience

Sample records for flottante shell pour

  1. Solutions multiples thermocapillaires en zone flottante à gravité nulle

    Science.gov (United States)

    Chénier, E.; Delcarte, C.; Labrosse, G.

    1998-04-01

    An original model is adopted to analyse the melted phase hydrodynamics, in the floating zone technique configuration for crystal growth. In particular, a small capillary scale located near the fusion fronts is taken into account. Its size turns out to influence significantly the flow structure. For the first time, multiple solutions are exhibited in zero gravity. Un modèle original a été adopté pour analyser l'hydrodynamique de la phase fondue pour la technique de la zone flottante, en croissance cristalline. En particulier, une petite échelle capillaire, située près des fronts de fusion, est prise en considération. Son extension se révèle influencer significativement la structure des écoulements. L'existence de solutions multiples est, pour la première fois, mise en évidence en gravité zéro.

  2. Le comportement des thons tropicaux autour des objets flottants: de l'étude des comportements individuels et collectifs à l'étude du piège écologique

    OpenAIRE

    Robert, Marianne

    2012-01-01

    Les recherches en halieutique ont pour objectif d’améliorer les connaissances sur le fonctionnement des populations de poissons afin de transférer celle-ci vers des outils de gestion. Ce travail de thèse repose sur un ensemble d’expériences et de modélisations destinées à approfondir notre compréhension générale du comportement associatif de poissons grands pélagiques avec des objets flottants à la surface de l’océan. Notre objectif est de tester si les milliers d’objets flottants artificiels...

  3. Une méthode de calcul par éléments finis de la résistence de vague des corps flottants ou immergés en théorie linéaire A Finite Elements Method for Computing the Resistance of Floating Or Submerged Bodies to Wave Action Using a Linear Theory

    OpenAIRE

    Cariou A.

    2006-01-01

    Pour calculer le potentiel de l'écoulement autour d'un corps en mouvement rectiligne uniforme, soit en fluide illimité (engin sous-marin), soit sur une mer infinie (corps flottant ou voisin de la surface libre), on se place dans le cadre du problème de Neumann extérieur ou du problème de Neumann Kelvin. Pour résoudre ces problèmes on se propose de délimiter autour de la carène un domaine fluide fini (,ri) dont les frontières sont : la carène (SC), une surface (SE) entourant la carène et évent...

  4. Méthode numérique de calcul du mouvement d'un corps flottant soumis à l'influence d'une houle périodique en théorie linéaire Numerical Method for Calculating the Movement of a Floating Body Subjected to the Influence of Theoretically Linear Wave Action

    Directory of Open Access Journals (Sweden)

    Chenot J. -L.

    2006-11-01

    Full Text Available Nous rappelons les équations linéaires du mouvement d'un corps flottant soumis à l'action d'une houle sinusoïdale simple, en précisant les simplifications qui apparaissent lorsque le corps est de révolution. On recherche une solution potentielle dans le domaine fluide, divisé en deux zones : la première zone entoure le corps à distance finie, la seconde est infinie. Dans la première zone, une solution de types éléments finis est adoptée, avec des éléments à huit nceuds, dans le cas général, et des triangles à trois noeuds pour les corps de révolution. Dans la zone numéro deux nous utilisons une solution analytique sous forme d'une série de fonctions tronquée, qui vérifie la condition de radiation. Le raccordement entre les deux zones est assuré exactement pour la dérivée normale du potentiel (vitesse normale, et une formulation du type optimal en moyenne quadratique permet également de raccorder le potentiel. La formulation adoptée permet de conserver tous les avantages de la méthode des éléments finis et, de ce fait, elle est spécialement adaptée à la réalisation d'un modèle numérique [6]. This article reviews the linear equations describing a floating body subject to the effect of a simple sinusoidal wave action, including the simplifications that appear when the body forms a surface of revolution. A potential solution is sought after in the fluid realm divided into two zones : (i one surrounding the body at a finite distance, and (ii the other being infinite. In the first zone, a solution of the finite-element type is adopted, with eight-node elements in the general case and with triangles with three nodes for bodies of revolution. In thé second zone, we use on analytic solution in the form of a series of truncated functions which checks the radiation condition. The connection between the two zones is made exactly for the normal derivative of the potentiel (normal velocity, and a formulation of the

  5. Une méthode de calcul par éléments finis de la résistence de vague des corps flottants ou immergés en théorie linéaire A Finite Elements Method for Computing the Resistance of Floating Or Submerged Bodies to Wave Action Using a Linear Theory

    Directory of Open Access Journals (Sweden)

    Cariou A.

    2006-11-01

    Full Text Available Pour calculer le potentiel de l'écoulement autour d'un corps en mouvement rectiligne uniforme, soit en fluide illimité (engin sous-marin, soit sur une mer infinie (corps flottant ou voisin de la surface libre, on se place dans le cadre du problème de Neumann extérieur ou du problème de Neumann Kelvin. Pour résoudre ces problèmes on se propose de délimiter autour de la carène un domaine fluide fini (,ri dont les frontières sont : la carène (SC, une surface (SE entourant la carène et éventuellement la portion de surface libre (SI. limitée par les lignes de flottaison de SC et SE. La solution à l'intérieur de (,ri est déterminée à l'aide d'une méthode d'éléments finis et elle est raccordée à la solution en domaine infini elle-même calculée grâce aux fonctions de Green du problème (ou solutions élémentaires. For computing the flow potential around a body in uniform rectilinear movement, either in an unlimited fluid (subsea croft or on an infinite sea (body floating near the free surface, consideration must be given ta the outside Neumann problem or ta the Neumann Kelvin problem. Ta solve these problems, this article proposes ta delimit a finite fluid realm (T: around the body. The limits of this realm are: I the body (SC, 2 a surface (SE surrounding the body, and eventually 3 the portion of free surface (SU bounded by the waterlines of SC and SE. The solution within iri is determined by a finite elements method, and it is related ta the solution in on infinite realm which in turn is computed by the Green functions of the problem (or elementary solutions.

  6. Shell supports

    DEFF Research Database (Denmark)

    Almegaard, Henrik

    2004-01-01

    A new statical and conceptual model for membrane shell structures - the stringer system - has been found. The principle was first published at the IASS conference in Copenhagen (OHL91), and later the theory has been further developed (ALMO3)(ALMO4). From the analysis of the stringer model it can...... be concluded that all membrane shells can be described by a limited number of basic configurations of which quite a few have free edges....

  7. ARC Code TI: Pour

    Data.gov (United States)

    National Aeronautics and Space Administration — Pour is a general-purpose information service framework designed to accommodate a wide variety of information types with support for high volume, low frequency...

  8. Shell worlds

    Science.gov (United States)

    Roy, Kenneth I.; Kennedy, Robert G., III; Fields, David E.

    2013-02-01

    The traditional concept of terraforming assumes ready availability of candidate planets with acceptable qualities: orbiting a star in its "Goldilocks zone", liquid water, enough mass, years longer than days, magnetic field, etc. But even stipulating affordable interstellar travel, we still might never find a good candidate elsewhere. Whatever we found likely would require centuries of heavy terraforming, just as Mars or Venus would here. Our increasing appreciation of the ubiquity of life suggests that any terra nova would already possess it. We would then face the dilemma of introducing alien life forms (us, our microbes) into another living world. Instead, we propose a novel method to create habitable environments for humanity by enclosing airless, sterile, otherwise useless planets, moons, and even large asteroids within engineered shells, which avoids the conundrum. These shells are subject to two opposing internal stresses: compression due to the primary's gravity, and tension from atmospheric pressure contained inside. By careful design, these two cancel each other resulting in zero net shell stress. Beneath the shell an Earth-like environment could be created similar in almost all respects to that of Home, except for gravity, regardless of the distance to the sun or other star. Englobing a small planet, moon, or even a dwarf planet like Ceres, would require astronomical amounts of material (quadrillions of tons) and energy, plus a great deal of time. It would be a quantum leap in difficulty over building Dyson Dots or industrializing our solar system, perhaps comparable to a mission across interstellar space with a living crew within their lifetime. But when accomplished, these constructs would be complete (albeit small) worlds, not merely large habitats. They could be stable across historic timescales, possibly geologic. Each would contain a full, self-sustaining ecology, which might evolve in curious directions over time. This has interesting implications

  9. Solidification of subcooled gallium poured into a vertical cylindrical mold

    OpenAIRE

    Dubovsky, Vadim; Harary, Itay; Assis, Eli; Ziskind, Gennady; Letan, Ruth

    2016-01-01

    The present investigation is aimed at the solidification of subcooled liquid gallium. The gallium, in its liquid state, is contained in a cylindrical shell of copper or polypropylene, and poured into the shell, which is immersed in a cold bath. The experimental degree of subcooling varied between 5°C and 45°C. The phenomena empirically observed have been simulated in four stages: subcooling of the liquid gallium down to its nucleation temperature, a rapid transfer from nucleation to the stabl...

  10. Offre pour nos membres

    CERN Multimedia

    Staff Association

    2016-01-01

    Walibi Rhône-Alpes accueille son événement Halloween FreakShow le week-end du 15 et 16 octobre puis tous les jours du 20 octobre au 02 novembre 2016 ! ouverture prolongée jusqu’à 19h et feu d’artifices chaque soir 29, 30 et 31 octobre ! Loup-garou show; 1 labyrinthe; jeu de piste sur le parc (et nombreux lots à gagner); animations (sculpture sur citrouilles et maquillage) et d'autres surpises ! Tarifs pour nos membres : Entrée "Zone terrestre": 23 € au lieu de 29 €. Entrée gratuite pour les enfants de moins de 3 ans, avec accès aux attractions limité. Parking gratuit.

  11. Informatique: tous pour un ... projet

    CERN Multimedia

    Delétraz, F; Requin, J-M

    2004-01-01

    "Pour des raisons de coût et d'efficacité, les chercheurs font de plus en plus travailler ensemble des ordinateurs éparpillés sur tous les continents. Pour faire avancer la science, tous les moyens et tous les réseaux sont bons" (1 page)

  12. Shell ontogeny in radiolarians

    Digital Repository Service at National Institute of Oceanography (India)

    Anderson, O.R.; Gupta, S.M.

    The ontogeny of the shells in modern and ancient radiolarian species, Acrosphaera cyrtodon were observed by scanning and transmission electron microscopy. The shells of A. cyrtodon were obtained from core samples collected from the Central Indian...

  13. Shell-like structures

    CERN Document Server

    Altenbach, Holm

    2011-01-01

    In this volume, scientists and researchers from industry discuss the new trends in simulation and computing shell-like structures. The focus is put on the following problems: new theories (based on two-dimensional field equations but describing non-classical effects), new constitutive equations (for materials like sandwiches, foams, etc. and which can be combined with the two-dimensional shell equations), complex structures (folded, branching and/or self intersecting shell structures, etc.) and shell-like structures on different scales (for example: nano-tubes) or very thin structures (similar

  14. Se déplacer en voiture à Boston : essai de mesure de circulation en temps réel par usage des floating car data (données flottantes automobiles

    Directory of Open Access Journals (Sweden)

    Gérald Billard

    2015-12-01

    Full Text Available Comment mesurer les temps de trajets réels des automobilistes dans les métropoles américaines ? Tout en introduisant la problématique de l’adaptation de l’urbanisme aux nouveaux enjeux de la mobilité aux États-Unis, cet article a pour objectif simple d’exposer une méthodologie développée afin de mesurer l’accessibilité d’un lieu donné. L’originalité de cette méthode est l’exploitation des données en ligne fournies en temps réel par le site TomTom.

  15. Dvorak. Concerto pour violoncelle / Francis Dresel

    Index Scriptorium Estoniae

    Dresel, Francis

    1992-01-01

    Uuest heliplaadist "Dvorak. Concerto pour violoncelle; Schumann: Concerto pour violoncelle. Orchestre Symphonique d'Estonie, Orchestre Symphonique de la Radio TV d'URSS, Neeme Järvi" Vogue "Archives Sovietiques" 651033 1978

  16. Molluscan shell colour.

    Science.gov (United States)

    Williams, Suzanne T

    2017-05-01

    The phylum Mollusca is highly speciose, and is the largest phylum in the marine realm. The great majority of molluscs are shelled, including nearly all bivalves, most gastropods and some cephalopods. The fabulous and diverse colours and patterns of molluscan shells are widely recognised and have been appreciated for hundreds of years by collectors and scientists alike. They serve taxonomists as characters that can be used to recognise and distinguish species, however their function for the animal is sometimes less clear and has been the focus of many ecological and evolutionary studies. Despite these studies, almost nothing is known about the evolution of colour in molluscan shells. This review summarises for the first time major findings of disparate studies relevant to the evolution of shell colour in Mollusca and discusses the importance of colour, including the effects of visual and non-visual selection, diet and abiotic factors. I also summarise the evidence for the heritability of shell colour in some taxa and recent efforts to understand the molecular mechanisms underpinning synthesis of shell colours. I describe some of the main shell pigments found in Mollusca (carotenoids, melanin and tetrapyrroles, including porphyrins and bile pigments), and their durability in the fossil record. Finally I suggest that pigments appear to be distributed in a phylogenetically relevant manner and that the synthesis of colour is likely to be energetically costly. © 2016 Cambridge Philosophical Society.

  17. Nuclear shell theory

    CERN Document Server

    de-Shalit, Amos; Massey, H S W

    1963-01-01

    Nuclear Shell Theory is a comprehensive textbook dealing with modern methods of the nuclear shell model. This book deals with the mathematical theory of a system of Fermions in a central field. It is divided into three parts. Part I discusses the single particle shell model. The second part focuses on the tensor algebra, two-particle systems. The last part covers three or more particle systems. Chapters on wave functions in a central field, tensor fields, and the m-Scheme are also presented. Physicists, graduate students, and teachers of nuclear physics will find the book invaluable.

  18. When It Rains, It Pours

    Science.gov (United States)

    Mills, Linda

    2012-01-01

    "It's raining, it's pouring, the old man is snoring!" "The itsy, bitsy spider crawled up the waterspout, down came the rain and washed the spider out. Out came the sun and dried up all the rain, and the itsy, bitsy spider went up the spout again." What do children's nursery rhymes have to do with the school library? The author begins by telling a…

  19. Shell Buckling Knockdown Factors

    Data.gov (United States)

    National Aeronautics and Space Administration — The Shell Buckling Knockdown Factor (SBKF) Project, NASA Engineering and Safety Center (NESC) Assessment #: 07-010-E, was established in March of 2007 by the NESC in...

  20. SHELL ISOTOPE GEOCHEMISTRY

    African Journals Online (AJOL)

    THE LAND SNAIL LIMICOLARIA KAMBEUL CHUDEAUI GERMAIN. IN THE ETHIOPIAN RIFT VALLEY: HABITAT, ECOLOGY AND. SHELL ISOTOPE GEOCHEMISTRY. Melanie J. Lengl, Henry F. Lamb',. Mohammed Umer Mohammed''* and Elias Dadebo4. 'NERC Isotope Geosciences Laboratory, Keyworth, Nottingham, ...

  1. Shelling of Homogeneous Media

    CERN Document Server

    Grimm, U

    2005-01-01

    A homogeneous medium is characterised by a point set in Euclidean space (for the atomic positions, say), together with some self-averaging property. Crystals and quasicrystals are homogeneous, but also many structures with disorder still are. The corresponding shelling is concerned with the number of points on shells around an arbitrary, but fixed centre. For non-periodic point sets, where the shelling depends on the chosen centre, a more adequate quantity is the averaged shelling, obtained by averaging over points of the set as centres. For homogeneous media, such an average is still well defined, at least almost surely (in the probabilistic sense). Here, we present a two-step approach for planar model sets.

  2. Shells and Patterns

    Science.gov (United States)

    Sutley, Jane

    2009-01-01

    "Shells and Patterns" was a project the author felt would easily put smiles on the faces of her fifth-graders, and teach them about unity and the use of watercolor pencils as well. It was thrilling to see the excitement in her students as they made their line drawings of shells come to life. For the most part, they quickly got the hang of…

  3. Contemporary nuclear shell models

    CERN Document Server

    Luo Yan An; Zhang Xia; Tan Yu Hong; Ning Ping Zhi

    2002-01-01

    The current status on the theoretical investigations of the nuclear shell model is reviewed, and the fundamental problems in shell-model studies are mentioned. Basically the shell-model uses a very intuitive approach to study the nuclear many-body dynamics in terms of valence particles. It assumes that the nucleons, belonging to a closed core, do not participate in the establishment of the nuclear spectrum. One of the main problems in the (traditional) shell model is to make a calculation feasible. With the explosive growth of the computational power, it is possible to carry out a 'Very Large Scale' shell model calculation. Nevertheless, whether such a calculation really helps authors' understanding of physics is still an open question. Furthermore, the case of the medium weight and heavy nuclei with configurations of 10 sup 1 sup 4 -10 sup 1 sup 8 remains out of reach. For these nuclei one still needs to truncate the huge shell model space to a manageable subspace. Recently, a useful formalism has been descr...

  4. HST/ACS observations of shell galaxies : inner shells, shell colours and dust

    NARCIS (Netherlands)

    Sikkema, G.; Carter, D.; Peletier, R. F.; Balcells, M.; Del Burgo, C.; Valentijn, E. A.

    Context. Shells in Elliptical Galaxies are faint, sharp-edged features, believed to provide evidence for a merger event. Accurate photometry at high spatial resolution is needed to learn on presence of inner shells, population properties of shells, and dust in shell galaxies. Aims. Learn more about

  5. Multi-Shell Hollow Nanogels with Responsive Shell Permeability

    Science.gov (United States)

    Schmid, Andreas J.; Dubbert, Janine; Rudov, Andrey A.; Pedersen, Jan Skov; Lindner, Peter; Karg, Matthias; Potemkin, Igor I.; Richtering, Walter

    2016-01-01

    We report on hollow shell-shell nanogels with two polymer shells that have different volume phase transition temperatures. By means of small angle neutron scattering (SANS) employing contrast variation and molecular dynamics (MD) simulations we show that hollow shell-shell nanocontainers are ideal systems for controlled drug delivery: The temperature responsive swelling of the inner shell controls the uptake and release, while the thermoresponsive swelling of the outer shell controls the size of the void and the colloidal stability. At temperatures between 32 °C shell. Computer simulations showed, that temperature induced switching of the permeability of the inner shell allows for the encapsulation in and release of molecules from the cavity. PMID:26984478

  6. NIF Double Shell outer/inner shell collision experiments

    Science.gov (United States)

    Merritt, E. C.; Loomis, E. N.; Wilson, D. C.; Cardenas, T.; Montgomery, D. S.; Daughton, W. S.; Dodd, E. S.; Desjardins, T.; Renner, D. B.; Palaniyappan, S.; Batha, S. H.; Khan, S. F.; Smalyuk, V.; Ping, Y.; Amendt, P.; Schoff, M.; Hoppe, M.

    2017-10-01

    Double shell capsules are a potential low convergence path to substantial alpha-heating and ignition on NIF, since they are predicted to ignite and burn at relatively low temperatures via volume ignition. Current LANL NIF double shell designs consist of a low-Z ablator, low-density foam cushion, and high-Z inner shell with liquid DT fill. Central to the Double Shell concept is kinetic energy transfer from the outer to inner shell via collision. The collision determines maximum energy available for compression and implosion shape of the fuel. We present results of a NIF shape-transfer study: two experiments comparing shape and trajectory of the outer and inner shells at post-collision times. An outer-shell-only target shot measured the no-impact shell conditions, while an `imaging' double shell shot measured shell conditions with impact. The `imaging' target uses a low-Z inner shell and is designed to perform in similar collision physics space to a high-Z double shell but can be radiographed at 16keV, near the viable 2DConA BL energy limit. Work conducted under the auspices of the U.S. DOE by LANL under contract DE-AC52-06NA25396.

  7. Snail Shell Science.

    Science.gov (United States)

    Matthews, Catherine

    1992-01-01

    Presents three inquiry-based lessons to develop the science process skills of observation, identification, and classification. Activities use whelk eggs and snail shells as the focus of the students' inquiries. Provides a list of 19 facts about whelks and snails. (MDH)

  8. Interventions for shell eggs

    Science.gov (United States)

    Eggs are the second riskiest foods regulated by the U.S. FDA. Less than 3% of shell eggs are pasteurized using a hot water process that unfortunately damages the appearance and functionality of the eggs. In addition, the current process adds more than $1.50 to the cost of a dozen eggs. Therefore, al...

  9. shells 1*ITODO, AU

    African Journals Online (AJOL)

    Michael Horsfall

    ABSTRACT: The removal of textile dyestuff from waste water was investigated in a batch sorption process using shea nut (Vitellaria paradoxa) shell activated carbon. The data were tested using the Rudishkevich – Dubinin and Temkin isotherm models. The result showed that removal efficiency increases with increase in ...

  10. Temporal structures in shell models

    DEFF Research Database (Denmark)

    Okkels, F.

    2001-01-01

    The intermittent dynamics of the turbulent Gledzer, Ohkitani, and Yamada shell-model is completely characterized by a single type of burstlike structure, which moves through the shells like a front. This temporal structure is described by the dynamics of the instantaneous configuration of the shell...

  11. Anatomy of successive helium-shell flashes: Stationary shell burning

    International Nuclear Information System (INIS)

    Sackmann, I.

    1980-01-01

    For successive helium-shell flashes, the amounts of helium and hydrogen burned were computed over the peak flash phase, over the total flash cycle, and over the quiet, interflash phase. It was found that the frequently made assumption of stationary shell burning is violated by the helium-shell flash for the first few flashes; here, over a total flash cycle, the helium-burning shell always progresses considerably faster outward than the hydrogen-burning shell. However, after about 15 flashes, coincident with the leveling out of the peaks of the helium shell, agreement with stationary shell burning is attained, both for the 3 M/sub sun/ and 6 M/sub sun/ cases

  12. 7 CFR 51.2002 - Split shell.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Split shell. 51.2002 Section 51.2002 Agriculture... Standards for Grades of Filberts in the Shell 1 Definitions § 51.2002 Split shell. Split shell means a shell... of the shell, measured in the direction of the crack. ...

  13. Plate shell structures of glass

    DEFF Research Database (Denmark)

    Bagger, Anne

    to their curved shape. A plate shell structure maintains a high stiffness-to-weight ratio, while facilitating the use of plane structural elements. The study focuses on using laminated glass panes for the load bearing facets. Various methods of generating a plate shell geometry are suggested. Together with Ghent......, such as facet size, imperfections, and connection characteristics. The critical load is compared to that of a similar, but smoothly curved, shell structure. Based on the investigations throughout the study, a set of guidelines for the structural design of plate shells of glass is proposed.......This thesis is a study of plate shell structures -- a type of shell structure with a piecewise plane geometry, organized so that the load bearing system is constituted by distributed in-plane forces in the facets. The high stiffness-to-weight ratio of smoothly curved shell structures is mainly due...

  14. Shells on elastic foundations

    International Nuclear Information System (INIS)

    Das, Y.C.; Kedia, K.K.

    1977-01-01

    No realistic analytical work in the area of Shells on Elastic Foundations has been reported in the literature. Various foundation models have been proposed by several authors. These models involve one or more than one parameters to characterise the foundation medium. Some of these models cannot be used to derive the basic equations governing the behaviour of shells on elastic foundations. In the present work, starting from an elastic continuum hypothesis, a mathematical model for foundation has been derived in curvilinear orthogonal coordinates by the help of principle of virtual displacements, treating one of the virtual displacements as known to satisfy certain given conditions at its edge surfaces. In this model, several foundation parameters can be considered and it can also be used for layered medium of both finite and infinite thickness. (Auth.)

  15. Particles and Shells

    CERN Document Server

    Palazzi, P

    2003-01-01

    The current understanding of particle masses in terms of quarks and their binding energy is not satisfactory. Both in atoms and in nuclei the organizing principle of stability is the shell structure, while this does not seem to play any role for particles. In order to explore the possibility that shells might also be relevant at this inner level of aggregation, atomic and nuclear stability are expressed by "stablines", alignments of the 1/3 power of the total number of constituents of the most stable configurations. Could similar patterns be found in the particle spectrum? By analyzing the distribution of particle lifetimes as a function of mass, stability peaks are recognized for mesons and for baryons and indeed the cube roots of their masses follow two distinct stablines. Such alignments would be a strong indication that the particles themselves are shell structured assuming only that each constituent contributes a constant amount to the total mass. This is incompatible with the prevalent view that the par...

  16. Wrinkling of Pressurized Elastic Shells

    KAUST Repository

    Vella, Dominic

    2011-10-01

    We study the formation of localized structures formed by the point loading of an internally pressurized elastic shell. While unpressurized shells (such as a ping-pong ball) buckle into polygonal structures, we show that pressurized shells are subject to a wrinkling instability. We study wrinkling in depth, presenting scaling laws for the critical indentation at which wrinkling occurs and the number of wrinkles formed in terms of the internal pressurization and material properties of the shell. These results are validated by numerical simulations. We show that the evolution of the wrinkle length with increasing indentation can be understood for highly pressurized shells from membrane theory. These results suggest that the position and number of wrinkles may be used in combination to give simple methods for the estimation of the mechanical properties of highly pressurized shells. © 2011 American Physical Society.

  17. Seismic analysis of axisymmetric shells

    International Nuclear Information System (INIS)

    Jospin, R.J.; Toledo, E.M.; Feijoo, R.A.

    1984-01-01

    Axisymmetric shells subjected to multiple support excitation are studied. The shells are spatialy discretized by the finite element method and in order to obtain estimates for the maximum values of displacements and stresses the response spectrum tecnique is used. Finally, some numerical results are presented and discussed in the case of a shell of revolution with vertical symmetry axis, subjected to seismic ground motions in the horizontal, vertical and rocking directions. (Author) [pt

  18. The Design of 3D-Printed Lattice-Reinforced Thickness-Varying Shell Molds for Castings.

    Science.gov (United States)

    Shangguan, Haolong; Kang, Jinwu; Yi, Jihao; Zhang, Xiaochuan; Wang, Xiang; Wang, Haibin; Huang, Tao

    2018-03-30

    3D printing technologies have been used gradually for the fabrication of sand molds and cores for castings, even though these molds and cores are dense structures. In this paper, a generation method for lattice-reinforced thickness-varying shell molds is proposed and presented. The first step is the discretization of the STL (Stereo Lithography) model of a casting into finite difference meshes. After this, a shell is formed by surrounding the casting with varying thickness, which is roughly proportional to the surface temperature distribution of the casting that is acquired by virtually cooling it in the environment. A regular lattice is subsequently constructed to support the shell. The outside surface of the shell and lattice in the cubic mesh format is then converted to STL format to serve as the external surface of the new shell mold. The internal surface of the new mold is the casting's surface with the normals of all of the triangles in STL format reversed. Experimental verification was performed on an Al alloy wheel hub casting. Its lattice-reinforced thickness-varying shell mold was generated by the proposed method and fabricated by the binder jetting 3D printing. The poured wheel hub casting was sound and of good surface smoothness. The cooling rate of the wheel hub casting was greatly increased due to the shell mold structure. This lattice-reinforced thickness-varying shell mold generation method is of great significance for mold design for castings to achieve cooling control.

  19. Stability Landscape of Shell Buckling

    Science.gov (United States)

    Virot, Emmanuel; Kreilos, Tobias; Schneider, Tobias M.; Rubinstein, Shmuel M.

    2017-12-01

    We measure the response of cylindrical shells to poking and identify a stability landscape, which fully characterizes the stability of perfect shells and imperfect ones in the case where a single defect dominates. We show that the landscape of stability is independent of the loading protocol and the poker geometry. Our results suggest that the complex stability of shells reduces to a low dimensional description. Tracking ridges and valleys of this landscape defines a natural phase-space coordinates for describing the stability of shells.

  20. The direct manipulation shell

    International Nuclear Information System (INIS)

    Allen, M.E.; Christiansen, M.

    1992-01-01

    Accelerator controls systems provide parameter display pages which allow the operator to monitor and manipulate selected control points in the system. Display pages are generally implemented as either hand-crafted, purpose-built programs; or by using a specialized display page layout tool. These two methods of display page development exhibit the classic trade-off between functionality vs. ease of implementation. In the Direct Manipulation Shell we approach the process of developing a display page in a manifestly object-oriented manner. This is done by providing a general framework for interactively instantiating and manipulating display objects. (author)

  1. 7 CFR 51.2289 - Shell.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Shell. 51.2289 Section 51.2289 Agriculture Regulations... Standards for Shelled English Walnuts (Juglans Regia) Definitions § 51.2289 Shell. Shell means the outer shell and/or the woody partition from between the halves of the kernel, and any fragments of either. ...

  2. IED Afrique, notre histoire pour le meilleur...

    International Development Research Centre (IDRC) Digital Library (Canada)

    IDRC CRDI

    De même, notre Conseil d'Administration peine à se mobiliser au service de la structure du fait de la spécificité ... crucial pour une organisation qui n'arrive pas à mobiliser des ressources suffisantes qui lui permettraient de ... La communication pour augmenter la notoriété et la visibilité de l'organisation auprès notamment ...

  3. Adaptive discretisation of shell problems

    Energy Technology Data Exchange (ETDEWEB)

    Hecht, A.; Carstensen, C.; Zarrabi, D. [Kiel Univ. (Germany)

    2000-07-01

    A seven parameter Reissner-Mindlin shell kinematic is employed for a elastoplastic material with hardening. The resulting nonlinear minimization problem is discretised within a finite element method on the mid surface of the shell. A posteriori error estimates are discussed and related adaptive algorithms are presented. Numerical examples illustrate the theoretical results. (orig.)

  4. Expert system development (ESD) shell

    International Nuclear Information System (INIS)

    Padmini, S.; Diwakar, M.P.; Rathode, N.C.; Bairi, B.R.

    1991-01-01

    An Expert System Development (ESD) Shell design implementation is desribed in detail. The shell provides high-level generic facilities for Knowledge Representation (KR) and inferencing and tools for developing user interfaces. Powerful set of tools in the shell relieves much of the programming burden in the ES development. The shell is written in PROLOG under IBM PC/AT. KR facilities are based on two very powerful formalisms namely, frames and rules. Inference Engine (IE) draws most of its power from unification and backward reasoning strategy in PROLOG. This basic mechanism is enhanced further by incorporating both forward and backward chaining of rules and frame-based inferencing. Overall programming style integrates multiple paradigms including logic, object oriented, access-oriented and imperative programming. This permits ES designer a lot of flexibility in organizing inference control. Creation and maintainance of knowledge base is a major activity. The shell, therefore, provides number of facilities to simplify these tasks. Shell design also takes note of the fact that final success of any system depends on end-user satisfaction and hence provides features to build use-friendly interfaces. The shell also provides a set of interfacing predicates so that it can be embedded within any PROLOG program to incorporate functionalilty of the shell in the user program. (author). 10 refs., 8 figs

  5. Boson Stars and Boson Shells

    Science.gov (United States)

    Kumar, Sanjeev; Kulshreshtha, Usha; Kulshreshtha, Daya Shankar

    2018-03-01

    In this work we present a broad formalism for a study of the models of black holes, boson stars, boson shells and wormholes. The studies of boson stars and boson shells in a theory involving Scalar field, U(1) gauge field and a shelf interacting scalar potential coupled to gravity in the presence of a cosmological constant Λ are presented in details.

  6. Molluscan shell evolution with review of shell calcification hypothesis

    Czech Academy of Sciences Publication Activity Database

    Furuhashi, T.; Schwarzinger, C.; Mikšík, Ivan; Smrž, Miloslav; Beran, A.

    2009-01-01

    Roč. 154, č. 3 (2009), s. 351-371 ISSN 1096-4959 Institutional research plan: CEZ:AV0Z50110509 Keywords : mollusca * shell * biomineralization Subject RIV: CE - Biochemistry Impact factor: 1.607, year: 2009

  7. MicroShell Minimalist Shell for Xilinx Microprocessors

    Science.gov (United States)

    Werne, Thomas A.

    2011-01-01

    MicroShell is a lightweight shell environment for engineers and software developers working with embedded microprocessors in Xilinx FPGAs. (MicroShell has also been successfully ported to run on ARM Cortex-M1 microprocessors in Actel ProASIC3 FPGAs, but without project-integration support.) Micro Shell decreases the time spent performing initial tests of field-programmable gate array (FPGA) designs, simplifies running customizable one-time-only experiments, and provides a familiar-feeling command-line interface. The program comes with a collection of useful functions and enables the designer to add an unlimited number of custom commands, which are callable from the command-line. The commands are parameterizable (using the C-based command-line parameter idiom), so the designer can use one function to exercise hardware with different values. Also, since many hardware peripherals instantiated in FPGAs have reasonably simple register-mapped I/O interfaces, the engineer can edit and view hardware parameter settings at any time without stopping the processor. MicroShell comes with a set of support scripts that interface seamlessly with Xilinx's EDK tool. Adding an instance of MicroShell to a project is as simple as marking a check box in a library configuration dialog box and specifying a software project directory. The support scripts then examine the hardware design, build design-specific functions, conditionally include processor-specific functions, and complete the compilation process. For code-size constrained designs, most of the stock functionality can be excluded from the compiled library. When all of the configurable options are removed from the binary, MicroShell has an unoptimized memory footprint of about 4.8 kB and a size-optimized footprint of about 2.3 kB. Since MicroShell allows unfettered access to all processor-accessible memory locations, it is possible to perform live patching on a running system. This can be useful, for instance, if a bug is

  8. Guides et formulaires | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Demande de subvention de recherche du CRDI · Budget de proposition · Lignes directrices du CRDI pour la préparation du rapport d'étape technique · Lignes directrices du CRDI pour la préparation du rapport technique final · Lignes directrices du CRDI pour les dépenses de projet admissibles · Lignes directrices pour la ...

  9. Instant Windows PowerShell

    CERN Document Server

    Menon, Vinith

    2013-01-01

    Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. A practical, hands-on tutorial approach that explores the concepts of PowerShell in a friendly manner, taking an adhoc approach to each topic.If you are an administrator who is new to PowerShell or are looking to get a good grounding in these new features, this book is ideal for you. It's assumed that you will have some experience in PowerShell and Windows Server, as well being familiar with the PowerShell command-line.

  10. Patterning of the turtle shell.

    Science.gov (United States)

    Moustakas-Verho, Jacqueline E; Cebra-Thomas, Judith; Gilbert, Scott F

    2017-08-01

    Interest in the origin and evolution of the turtle shell has resulted in a most unlikely clade becoming an important research group for investigating morphological diversity in developmental biology. Many turtles generate a two-component shell that nearly surrounds the body in a bony exoskeleton. The ectoderm covering the shell produces epidermal scutes that form a phylogenetically stable pattern. In some lineages, the bones of the shell and their ectodermal covering become reduced or lost, and this is generally associated with different ecological habits. The similarity and diversity of turtles allows research into how changes in development create evolutionary novelty, interacting modules, and adaptive physiology and anatomy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. 40 Years of Shell Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-02-15

    Shell has been using scenario planning for four decades. During that time these scenarios have helped the company and governments across the world to make better strategic choices. Scenarios provide lenses that help see future prospects more clearly, make richer judgments and be more sensitive to uncertainties. Discover how the Shell Scenarios team has helped guide decision makers at major moments in history and get a peek at the team future focus, including the intricate relationship between energy, water and food.

  12. Isogeometric shell formulation based on a classical shell model

    KAUST Repository

    Niemi, Antti

    2012-09-04

    This paper constitutes the first steps in our work concerning isogeometric shell analysis. An isogeometric shell model of the Reissner-Mindlin type is introduced and a study of its accuracy in the classical pinched cylinder benchmark problem presented. In contrast to earlier works [1,2,3,4], the formulation is based on a shell model where the displacement, strain and stress fields are defined in terms of a curvilinear coordinate system arising from the NURBS description of the shell middle surface. The isogeometric shell formulation is implemented using the PetIGA and igakit software packages developed by the authors. The igakit package is a Python package used to generate NURBS representations of geometries that can be utilised by the PetIGA finite element framework. The latter utilises data structures and routines of the portable, extensible toolkit for scientific computation (PETSc), [5,6]. The current shell implementation is valid for static, linear problems only, but the software package is well suited for future extensions to geometrically and materially nonlinear regime as well as to dynamic problems. The accuracy of the approach in the pinched cylinder benchmark problem and present comparisons against the h-version of the finite element method with bilinear elements. Quadratic, cubic and quartic NURBS discretizations are compared against the isoparametric bilinear discretization introduced in [7]. The results show that the quadratic and cubic NURBS approximations exhibit notably slower convergence under uniform mesh refinement as the thickness decreases but the quartic approximation converges relatively quickly within the standard variational framework. The authors future work is concerned with building an isogeometric finite element method for modelling nonlinear structural response of thin-walled shells undergoing large rigid-body motions. The aim is to use the model in a aeroelastic framework for the simulation of flapping wings.

  13. Approches novatrices pour la création d'emplois pour les jeunes et ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    En Afrique de l'Est, malgré des taux de croissance impressionnants, la réduction de la pauvreté et la création d'emplois demeurent limitées, en particulier pour les jeunes. Compte tenu de l'ampleur de la croissance démographique en Afrique et de l'inaptitude du secteur structuré à créer des emplois pour les jeunes, ...

  14. De meilleurs emplois pour l'Asie

    International Development Research Centre (IDRC) Digital Library (Canada)

    Offrir de meilleurs emplois en Asie exigera des interventions créatives de la part des gouvernements, des employeurs et des entrepreneurs. Le CRDI aide les établisse- ments de recherche à trouver des .... de dollars en 2014, ont entraîné une expansion majeure des emplois pour les. Bangladaises. On s'attend à ce que ...

  15. Foam shell project: Progress report

    International Nuclear Information System (INIS)

    Overturf, G.; Reibold, B.; Cook, B.; Schroen-Carey, D.

    1994-01-01

    The authors report on their work to produce a foam shell target for two possible applications: (1) as liquid-layered cryogenic target on Omega Upgrade, and (2) as a back-up design for the NIF. This target consists of a roughly 1 mm diameter and 100 μm thick spherical low-density foam shell surrounding a central void. The foam will be slightly overfilled with liquid D 2 or DT, the overfilled excess being symmetrically distributed on the inside of the shell and supported by thermal gradient techniques. The outside of the foam is overcoated with full density polymer which must be topologically smooth. The technology for manufacturing this style of foam shell involves microencapsulation techniques and has been developed by the Japanese at ILE. Their goal is to determine whether this technology can be successfully adapted to meet US ICF objectives. To this end a program of foam shell development has been initiated at LLNL in collaboration with both the General Atomics DOE Target Fabrication Contract Corporation and the Target Fabrication Group at LLE

  16. Windows PowerShell 20 Bible

    CERN Document Server

    Lee, Thomas; Schill, Mark E; Tanasovski, Tome

    2011-01-01

    Here's the complete guide to Windows PowerShell 2.0 for administrators and developers Windows PowerShell is Microsoft's next-generation scripting and automation language. This comprehensive volume provides the background that IT administrators and developers need in order to start using PowerShell automation in exciting new ways. It explains what PowerShell is, how to use the language, and specific ways to apply PowerShell in various technologies. Windows PowerShell is Microsoft's standard automation tool and something that every Windows administrator will eventually have to understand; this b

  17. Shell model Monte Carlo methods

    International Nuclear Information System (INIS)

    Koonin, S.E.

    1996-01-01

    We review quantum Monte Carlo methods for dealing with large shell model problems. These methods reduce the imaginary-time many-body evolution operator to a coherent superposition of one-body evolutions in fluctuating one-body fields; resultant path integral is evaluated stochastically. We first discuss the motivation, formalism, and implementation of such Shell Model Monte Carlo methods. There then follows a sampler of results and insights obtained from a number of applications. These include the ground state and thermal properties of pf-shell nuclei, thermal behavior of γ-soft nuclei, and calculation of double beta-decay matrix elements. Finally, prospects for further progress in such calculations are discussed. 87 refs

  18. Learning Shell scripting with Zsh

    CERN Document Server

    Festari, Gaston

    2014-01-01

    A step-by-step tutorial that will teach you, through real-world examples, how to configure and use Zsh and its various features. If you are a system administrator, developer, or computer professional involved with UNIX who are looking to improve on their daily tasks involving the UNIX shell, ""Learning Shell Scripting with Zsh"" will be great for you. It's assumed that you have some familiarity with an UNIX command-line interface and feel comfortable with editors such as Emacs or vi.

  19. Adaptative mixed methods to axisymmetric shells

    International Nuclear Information System (INIS)

    Malta, S.M.C.; Loula, A.F.D.; Garcia, E.L.M.

    1989-09-01

    The mixed Petrov-Galerkin method is applied to axisymmetric shells with uniform and non uniform meshes. Numerical experiments with a cylindrical shell showed a significant improvement in convergence and accuracy with adaptive meshes. (A.C.A.S.) [pt

  20. Method and apparatus for an inflatable shell

    Science.gov (United States)

    Johnson, Christopher J. (Inventor)

    2012-01-01

    A method of assembling an inflatable shell of a structure comprises folding a plurality of shell sections about a set of fold lines and integrating the plurality of shell sections together with one another to form the shell. In another embodiment, an inflatable shell comprises a plurality of shell sections, each shell section having two pairs of fold lines for folding into stowage comprising a first gore section having a plurality of first gore panels layered and collectively folded about at a first set of fold lines. Each layer of the first gore panels and second gore panels are configured such that, once the first gore panel and second gore panel are attached to one another at the respective side edges of each panel, the lines of attachment forming a second set of fold lines for the shell section. A system and method for fabricating gore panels is also disclosed.

  1. Pitié pour les grandes villes !

    Directory of Open Access Journals (Sweden)

    Jérôme Monnet

    1997-02-01

    Full Text Available Roger Caillois disait, en 1938, qu´il existe "une représentation de la grande ville, assez puissante sur les imaginations pour que jamais en pratique ne soit posée la question de son exactitude, créée de toute pièce par le livre, assez répandue néanmoins pour faire partie de l´atmosphère mentale collective et posséder par suite une certaine force de contrainte"(Le mythe et l´homme, p.156 [c´est lui qui souligne]. En 1996, la presse française a consacré dossiers et articles à "Habitat II...

  2. Solutocapillary convection in spherical shells

    Science.gov (United States)

    Subramanian, Pravin; Zebib, Abdelfattah; McQuillan, Barry

    2005-01-01

    A linear stability study of solutocapillary driven Marangoni instabilities in small spherical shells is presented. The shells contain a binary fluid with an evaporating solvent. The viscosity is a strong function of the solvent concentration, the inner surface of the shell is assumed impermeable and stress free, while nonlinear boundary conditions are modeled and prescribed at the receding outer boundary. A time-dependent diffusive state is possible and may lose stability through the Marangoni mechanism due to surface tension dependence on solvent concentration (buoyant forces are negligible in this microscale problem). A frozen-time or quasisteady state linear stability analysis is performed to compute the critical Reynolds number and degree of surface harmonics, as well as the maximum growth rate of perturbations at specified parameters. The development of maximum growth rates in time was also computed by solving the initial value problem with random initial conditions. Results from both approaches are in good agreement except at short times where there is dependence on initial conditions. The physical problem models the manufacturing of spherical shells used as targets in inertial confinement fusion experiments where perfect sphericity is demanded for efficient fusion ignition. It is proposed that the Marangoni instability might be the source of observed surface roughness. Comparisons with the available experiments are made with reasonable qualitative and quantitative agreement.

  3. Shell formation and nuclear masses

    Energy Technology Data Exchange (ETDEWEB)

    Zuker, A. P. [IPHC, IN2P3-CNRS, Universite Louis Pasteur, F-67037 Strasbourg (France)]. e-mail: Andres.Zuker@IReS.in2p3.fr

    2008-12-15

    We describe the basic mechanisms responsible for nuclear bulk properties and shell formation incorporated in the Duflo Zuker models. The emphasis is put on explaining why functionals of the occupancies can be so efficient in accounting for data with minimal computational effort. (Author)

  4. A KIRCHHOFF THIN SHELL THEORY,

    Science.gov (United States)

    imposing the principal of virtual work on the calss of deformations which satisfy the Kirchhoff hypotheses, i.e. those deformations which carry normals to...physically realistic unless the shell is in fact thin. Imposing the principal of virtual work yields a system of differential equations for the three

  5. Tube in shell heat exchangers

    International Nuclear Information System (INIS)

    Hayden, O.; Willby, C.R.; Sheward, G.E.; Ormrod, D.T.; Firth, G.F.

    1980-01-01

    An improved tube-in-shell heat exchanger to be used between liquid metal and water is described for use in the liquid metal coolant system of fast breeder reactors. It is stated that this design is less prone to failures which could result in sodium water reactions than previous exchangers. (UK)

  6. Nonlinear theory of elastic shells

    International Nuclear Information System (INIS)

    Costa Junior, J.A.

    1979-08-01

    Nonlinear theory of elastic shells is developed which incorporates both geometric and physical nonlinearities and which does not make use of the well known Love-Kirchhoff hypothesis. The resulting equations are formulated in tensorial notation and are reduced to the ones of common use when simplifying assumptions encountered in the especific litterature are taken. (Author) [pt

  7. Shell theorem for spontaneous emission

    DEFF Research Database (Denmark)

    Kristensen, Philip Trøst; Mortensen, Jakob Egeberg; Lodahl, Peter

    2013-01-01

    and therefore is given exactly by the dipole approximation theory. This surprising result is a spontaneous emission counterpart to the shell theorems of classical mechanics and electrostatics and provides insights into the physics of mesoscopic emitters as well as great simplifications in practical calculations....

  8. Collapse analysis of toroidal shell

    International Nuclear Information System (INIS)

    Pomares, R.J.

    1990-01-01

    This paper describes a study performed to determine the collapse characteristics of a toroidal shell using finite element method (FEM) analysis. The study also included free drop testing of a quarter scale prototype to verify the analytical results. The full sized toroidal shell has a 24-inch toroidal diameter with a 24-inch tubal diameter. The shell material is type 304 strainless steel. The toroidal shell is part of the GE Model 2000 transportation packaging, and acts as an energy absorbing device. The analyses performed were on a full sized and quarter scaled models. The finite element program used in all analyses was the LIBRA code. The analytical procedure used both the elasto-plastic and large displacement options within the code. The loading applied in the analyses corresponded to an impact of an infinite rigid plane oriented normal to the drop direction vector. The application of the loading continued incrementally until the work performed by the deforming structure equalled the kinetic energy developed in the free fall. The comparison of analysis and test results showed a good correlation

  9. (Oil Palm Shell) Lightweight Concrete

    African Journals Online (AJOL)

    The compressive strength as destructive test and, ultrasonic pulse velocity (UPV) and dynamic modulus of elasticity (Ed) as non-destructive tests have been carried out on a new lightweight concrete produced using oil palm shell (OPS) as coarse aggregate, as a way to establish the usefulness of these tests to determine the ...

  10. Shell structure of octupole deformation

    International Nuclear Information System (INIS)

    Zhang Xizhen; Dong Baoguo

    1992-01-01

    A convenient definition of intrinsic frame of an octupole deformed shape was proposed recently. The octupole deformation potential was expanded on the bases of irreducible representations of group O h . Based on the parameterization given in previous paper, the shell structures of octupole deformation which cover all possible octupole deformed shapes were studied

  11. Shell morphology of core-shell latexes based on conductive polymers

    NARCIS (Netherlands)

    Huijs, F.M; Vercauteren, F.F.; de Ruiter, B.; Kalicharan, D; Hadziioannou, G

    Core-shell latexes with a conductive shell can be used to prepare transparent conducting layers. We have focussed on the relation between the conducting polymer content and the shell morphology and on its influence on conductivity. At low polypyrrole (PPy) concentrations the shell has a smooth

  12. Vibrations of Thin Piezoelectric Shallow Shells

    Indian Academy of Sciences (India)

    Abstract. In this paper we consider the eigenvalue problem for piezoelectric shallow shells and we show that, as the thickness of the shell goes to zero, the eigensolutions of the three-dimensional piezoelectric shells converge to the eigensolutions of a two-dimensional eigenvalue problem.

  13. 21 CFR 886.3800 - Scleral shell.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Scleral shell. 886.3800 Section 886.3800 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Prosthetic Devices § 886.3800 Scleral shell. (a) Identification. A scleral shell is a...

  14. 7 CFR 983.29 - Shelled pistachios.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Shelled pistachios. 983.29 Section 983.29 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements..., ARIZONA, AND NEW MEXICO Definitions § 983.29 Shelled pistachios. Shelled pistachios means pistachio...

  15. Centre de recherches pour le développement international ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    André Lavoie

    Pour tous les gouverneurs à l'exclusion du président du Conseil : 410 CAD par jour;. •. Pour le président du Conseil : 420 CAD par jour; b) Pour ce qui est de la préparation, la présence et la participation aux réunions des comités du. Conseil, les honoraires des gouverneurs doivent être versés selon des taux équivalant à ...

  16. Myanmar : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Programme: Governance and Justice ... La création de zones économiques frontalières constitue une importante stratégie d'industrialisation pour la Thaïlande et ouvre de nouvelles perspectives pour deux ... Una Hakika : Porter à grande échelle les solutions numériques pour la gestion des conflits au Kenya et en Birmanie.

  17. Tunisie : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Élaboration et essai pilote de modèles d'affaires pour obtenir des résultats à vaste échelle pour la transformation mécanisée des plantes fourragères. Projet. On retrouve en Afrique du Nord des écosystèmes marginaux, ainsi qu'une grande population rurale qui dépend sur des systèmes de cultures irriguées pour leur ...

  18. Publications | Page 195 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... a caractérisé un espace pastoral en utilisant une approche écologique. Il s''agit de la dendrométrie pour l''étude des peuplements ligneux et la méthode phytoécologique pour la végétation. Les... Plateforme participative d'information pour l'adaptation des communautés vulnérables aux changements climatiques : rapport ...

  19. Publications | Page 77 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La prévention et la gestion de la cryptosporidiose sont lourdes pour les hôpitaux et pour les vétérinaires. Il ressort de travaux de recherche soutenus par le CRDI sur les risques pour la santé présents dans les petites fermes laitières situées dans des régions urbaines pauvres du Kenya qu'il est plus dangereux de manger ...

  20. Publications | Page 79 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La prévention et la gestion de la cryptosporidiose sont lourdes pour les hôpitaux et pour les vétérinaires. Il ressort de travaux de recherche soutenus par le CRDI sur les risques pour la santé présents dans les petites fermes laitières situées dans des régions urbaines pauvres du Kenya qu'il est plus dangereux de manger ...

  1. Publications | Page 187 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La valeur de l'environnement – Faire appel à l'économie pour forger un avenir sous le signe de la durabilité. L'économie de l'environnement permet de déterminer les causes sous-jacentes des problèmes environnementaux et de trouver des solutions bénéfiques pour la population comme pour la planète. Depuis 1993, le ...

  2. Publications | Page 166 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La valeur de l'environnement – Faire appel à l'économie pour forger un avenir sous le signe de la durabilité. L'économie de l'environnement permet de déterminer les causes sous-jacentes des problèmes environnementaux et de trouver des solutions bénéfiques pour la population comme pour la planète. Depuis 1993, le ...

  3. Plaidoyer pour les oreilles | LAWSON | Journal de la Recherche ...

    African Journals Online (AJOL)

    Un counselling a été systématique prodigué comportant le principe de base et les 10 règles qui concourent à expliciter la proscription du coton-tige pour le nettoyage. Conclusion : Ce travail est un plaidoyer pour proscrire l'utilisation du coton-tige ou de tous autres instruments pour enlever le cérumen, ce qui est inutile, ...

  4. The effect of pouring time on the dimensional stability of casts made from conventional and extended-pour irreversible hydrocolloids by 3D modelling

    Directory of Open Access Journals (Sweden)

    Hasan Ö. Gümüş

    2015-09-01

    Conclusion: All of the conventional and extended-pour impression materials tested in this study can be poured up to 24 hours with accuracy, if impressions are correctly stored. Extended-pour impression materials (ColorChange, Hydrogum 5, and Hydrocolor 5 can be poured up to 120 hours, if stored correctly.

  5. Design aids for stiffened composite shells with cutouts

    CERN Document Server

    Sahoo, Sarmila

    2017-01-01

    This book focuses on the free vibrations of graphite-epoxy laminated composite stiffened shells with cutout both in terms of the natural frequencies and mode shapes. The dynamic analysis of shell structures, which may have complex geometry and arbitrary loading and boundary conditions, is solved efficiently by the finite element method, even including cutouts in shells. The results may be readily used by practicing engineers dealing with stiffened composite shells with cutouts. Several shell forms viz. cylindrical shell, hypar shell, conoidal shell, spherical shell, saddle shell, hyperbolic paraboloidal shell and elliptic paraboloidal shell are considered in the book. The dynamic characteristics of stiffened composite shells with cutout are described in terms of the natural frequency and mode shapes. The size of the cutouts and their positions with respect to the shell centre are varied for different edge constraints of cross-ply and angle-ply laminated composite shells. The effects of these parametric variat...

  6. Double containment shell for nuclear power plants

    International Nuclear Information System (INIS)

    Sykora, D.

    1977-01-01

    A double containment shell is proposed for nuclear power plants, especially those equipped with pressurized water reactors. The shell offers increased environmental protection from primary circuit accidents. The inner shell is built of steel or concrete while the outer shell is always built of concrete. The space between the two shells is filled with water and is provided with several manholes and with stiffeners designed for compensation for load due to the water hydrostatic pressure. Water serves the airtight separation of the containment shell inside from the environment and the absorption of heat released in a primary circuit accident. In case the inner shell is made of concrete, it is provided with heat-removal tubes in-built in its walls ensuring rapid heat transfer from the inside of the containment to the water in the interwall space. (Z.M.)

  7. Turbine blade with spar and shell

    Science.gov (United States)

    Davies, Daniel O [Palm City, FL; Peterson, Ross H [Loxahatchee, FL

    2012-04-24

    A turbine blade with a spar and shell construction in which the spar and the shell are both secured within two platform halves. The spar and the shell each include outward extending ledges on the bottom ends that fit within grooves formed on the inner sides of the platform halves to secure the spar and the shell against radial movement when the two platform halves are joined. The shell is also secured to the spar by hooks extending from the shell that slide into grooves formed on the outer surface of the spar. The hooks form a serpentine flow cooling passage between the shell and the spar. The spar includes cooling holes on the lower end in the leading edge region to discharge cooling air supplied through the platform root and into the leading edge cooling channel.

  8. Indentation of Ellipsoidal and Cylindrical Elastic Shells

    KAUST Repository

    Vella, Dominic

    2012-10-01

    Thin shells are found in nature at scales ranging from viruses to hens\\' eggs; the stiffness of such shells is essential for their function. We present the results of numerical simulations and theoretical analyses for the indentation of ellipsoidal and cylindrical elastic shells, considering both pressurized and unpressurized shells. We provide a theoretical foundation for the experimental findings of Lazarus etal. [following paper, Phys. Rev. Lett. 109, 144301 (2012)PRLTAO0031-9007] and for previous work inferring the turgor pressure of bacteria from measurements of their indentation stiffness; we also identify a new regime at large indentation. We show that the indentation stiffness of convex shells is dominated by either the mean or Gaussian curvature of the shell depending on the pressurization and indentation depth. Our results reveal how geometry rules the rigidity of shells. © 2012 American Physical Society.

  9. Recent developments in anisotropic heterogeneous shell theory

    CERN Document Server

    Grigorenko, Alexander Ya; Grigorenko, Yaroslav M; Vlaikov, Georgii G

    2016-01-01

    This volume focuses on the relevant general theory and presents some first applications, namely those based on classical shell theory. After a brief introduction, during which the history and state-of-the-art are discussed, the first chapter presents the mechanics of anisotropic heterogeneous shells, covering all relevant assumptions and the basic relations of 3D elasticity, classical and refined shell models. The second chapter examines the numerical techniques that are used, namely discrete orthogonalization, spline-collocation and Fourier series, while the third highlights applications based on classical theory, in particular, the stress-strain state of shallow shells, non-circular shells, shells of revolution, and free vibrations of conical shells. The book concludes with a summary and an outlook bridging the gap to the second volume.

  10. Læren fra Shell

    DEFF Research Database (Denmark)

    Ørding Olsen, Anders

    2017-01-01

    Hvad kan afsløringerne om Shells mere end 25 år gamle viden om klimaforandringer lære virksomheder om disruption og strategi? Først og fremmest at undgå at se disruption som en mulig trussel, men i stedet som en fremtidig realitet og chance for vækst......Hvad kan afsløringerne om Shells mere end 25 år gamle viden om klimaforandringer lære virksomheder om disruption og strategi? Først og fremmest at undgå at se disruption som en mulig trussel, men i stedet som en fremtidig realitet og chance for vækst...

  11. The shell coal gasification process

    Energy Technology Data Exchange (ETDEWEB)

    Koenders, L.O.M.; Zuideveld, P.O. [Shell Internationale Petroleum Maatschappij B.V., The Hague (Netherlands)

    1995-12-01

    Future Integrated Coal Gasification Combined Cycle (ICGCC) power plants will have superior environmental performance and efficiency. The Shell Coal Gasification Process (SCGP) is a clean coal technology, which can convert a wide range of coals into clean syngas for high efficiency electricity generation in an ICGCC plant. SCGP flexibility has been demonstrated for high-rank bituminous coals to low rank lignites and petroleum coke, and the process is well suited for combined cycle power generation, resulting in efficiencies of 42 to 46% (LHV), depending on choice of coal and gas turbine efficiency. In the Netherlands, a 250 MWe coal gasification combined cycle plant based on Shell technology has been built by Demkolec, a development partnership of the Dutch Electricity Generating Board (N.V. Sep). The construction of the unit was completed end 1993 and is now followed by start-up and a 3 year demonstration period, after that the plant will be part of the Dutch electricity generating system.

  12. Atomic inner-shell physics

    International Nuclear Information System (INIS)

    Crasemann, B.

    1985-01-01

    This book discusses: relativistic and quantum electrodynamic effects on atomic inner shells; relativistic calculation of atomic transition probabilities; many-body effects in energetic atomic transitions; Auger Electron spectrometry of core levels of atoms; experimental evaluation of inner-vacancy level energies for comparison with theory; mechanisms for energy shifts of atomic K-X rays; atomic physics research with synchrotron radiation; investigations of inner-shell states by the electron energy-loss technique at high resolution; coherence effects in electron emission by atoms; inelastic X-ray scattering including resonance phenomena; Rayleigh scattering: elastic photon scattering by bound electrons; electron-atom bremsstrahlung; X-ray and bremsstrahlung production in nuclear reactions; positron production in heavy-ion collisions, and X-ray processes in heavy-ion collisions

  13. Sound Radiation of Cylindrical Shells

    Directory of Open Access Journals (Sweden)

    B Alzahabi

    2016-09-01

    Full Text Available The acoustic signature of submarines is very critical in such high performance structure. Submarines are not only required to sustain very high dynamic loadings at all time, but also being able maneuver and perform their functions under sea without being detected by sonar systems. Submarines rely on low acoustic signature level to remain undetected. Reduction of sound radiation is most efficiently achieved at the design stage. Acoustic signatures may be determined by considering operational scenarios, and modal characteristics. The acoustic signature of submarines is generally of two categories; broadband which has a continuous spectrum; and a tonal noise which has discrete frequencies. The nature of sound radiation of submarine is fiction of its speed. At low speed the acoustic signature is dominated by tonal noise, while at high speed, the acoustic signature is mainly dominated by broadband noise. Submarine hulls are mainly constructed of circular cylindrical shells. Unlike that of simpler structures such as beams and plates, the modal spectrum of cylindrical shell exhibits very unique characteristics. Mode crossing, the uniqueness of modal spectrum, and the redundancy of modal constraints are just to name a few. In cylindrical shells, the lowest natural frequency is not necessarily associated with the lowest wave index. In fact, the natural frequencies do not fall in ascending order of the wave index either. Solution of the vibration problem of cylindrical shells also indicates repeated natural frequencies. These modes are referred to as double peak frequencies. Mode shapes associated with each one of the natural frequencies are usually a combination of Radial (flexural, Longitudinal (axial, and Circumferential (torsional modes. In this paper, the wave equation will be set up in terms of the pressure fluctuations, p(x, t. It will be demonstrated that the noise radiation is a fluctuating pressure wave.

  14. Buckling shells are also swimmers

    Science.gov (United States)

    Quilliet, Catherine; Dyfcom Bubbleboost Team

    We present an experimental and numerical study on the displacement of shells undergoing deformations in a fluid. When submitted to cycles of pressure difference between outside and inside, a shell buckles and debuckles, showing a succession of shapes and a dynamics that are different during the two phases. Hence such objects are likely to swim, including at low Reynolds (microscopic scale). We studied the swimming of buckling/debuckling shells at macroscopic scale using different approaches (force quantization, shape recording, displacement along a frictionless rail, study of external flow using PIV), and showed that inertia plays a role in propulsion, even in situations where dimensionless numbers correspond also to microswimmers in water. Different fluid viscosities were explored, showing an optimum for the displacement. Interestingly, the most favorable cases lead to displacements in the same direction and sense during both motor stroke (buckling phase) and recovery stroke (de-buckling phase). This work opens the route for the synthesis with high throughput of abusively simple synthetic swimmers, possibly gathered into nanorobots, actuated by a scalar field such as the pressure in echographic devices. Universite Grenoble Alpes, CNRS, European Research Council.

  15. Un logiciel pour la justice | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    28 oct. 2010 ... Evsys peut par ailleurs être adapté pour répondre aux besoins spécifiques d'un organisme. À LIRE ÉGALEMENT. HURIDOCS Site Web de Human Rights Information and DOCumentation Systems, International (HURIDOCS). HuriSearch. Moteur permettant de faire des recherches dans les sites Web de ...

  16. The Influence of the Melt-Pouring Temperature and Inoculant Content on the Macro and Microstructure of the IN713C Ni-Based Superalloy

    Science.gov (United States)

    Matysiak, Hubert; Zagorska, Malgorzata; Balkowiec, Alicja; Adamczyk-Cieslak, Boguslawa; Dobkowski, Krzysztof; Koralnik, Mateusz; Cygan, Rafal; Nawrocki, Jacek; Cwajna, Jan; Kurzydlowski, Krzysztof J.

    2016-01-01

    The aim of this work was to determine the effect of melt-pouring temperature T m and inoculant (cobalt aluminate—CoAl2O4) concentration in the prime coat of the shell mold on the macro- and microstructure of the IN713C superalloy. The results show that cobalt aluminate is an effective modifier of the IN713C superalloy, which causes refinement of the equiaxed grains (EX) and a reduction of the fraction and size of the columnar grains on the casting surface. Also, the melt-pouring temperature in the range of 1450-1520°C was found to influence the mean EX grain size. Based on the results of differential thermal analysis of the alloy and detailed microstructure characterization, a sequence of precipitations has been proposed that advances current understanding of processes that take place during alloy solidification and casting cooling.

  17. Changements climatiques | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'objectif du programme Changements climatiques consiste à appuyer des partenariats et des réseaux visant à rassembler des données probantes pour trouver des solutions et utiliser les technologies en vue d'obtenir des gains sociaux et économiques et d'atténuer les effets des changements climatiques pour l'avenir.

  18. Publications | Page 13 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Bien que la recherche a largement montré que les adolescents ont besoin de réseaux sociaux positifs et de connexions interpersonnelles – capital social positif – pour devenir des adultes productifs et socialement responsables, le capital social, son fonctionnement et le rôle essentiel qu'il joue pour diminuer la délinquance ...

  19. Rapports financiers trimestriels | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Rapports financiers trimestriels. 2017. Rapport financier trimestriel pour le trimestre qui a pris fin le 30 septembre 2017 · Rapport financier trimestriel pour le trimestre qui a pris fin le 30 juin 2017 · Analyse de la direction et États financiers 2016–2017 ...

  20. Approximation point par point pour la resolution du probleme de ...

    African Journals Online (AJOL)

    Approximation point par point pour la resolution du probleme de dirichlet dans un disque pour l'equation elliptique du second ordre a coefficients constants dans le cas ou les racines de l'equation caracteristique sont distinctes. AMJ Tchalla, K Tcharie ...

  1. Villes durables intelligentes | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    6 juin 2016 ... Smart Cities for Sustainable Development. Elsa Estevez, Nuno Vasco Lopes et Tomasz Janowski. On prévoit que de 2014 à 2050, la population urbaine mondiale devrait croître de 63 pour cent, comparativement à une croissance de la population mondiale globale de 32 pour cent pendant la même ...

  2. Inde | Page 119 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The death of the main breadwinner, a sick family member who requires medical attention, theft, a fire, or a flood—these misfortunes can wipe out a lifetime of hard work. Read more about Selling security to the poor. Langue English. En 1989, alors qu'il travaillait pour l'Organisation des Nations Unies pour l'agriculture et ...

  3. Livres | Page 31 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Management of Water Demand in Africa and the Middle East : Current Practices and Future Needs. Partout en Afrique et au Moyen-Orient, les réserves d'eau potable pour la culture et la transformation des aliments, les utilisations domestiques et urbaines et, ainsi que pour les activités indust. Directeur(s) : David B. Brooks, ...

  4. Publications | Page 125 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ÉTUDE DE CAS — Chili : Santé, environnement et culture autochtone. Un regain de vie pour les collectivités Mapuche. Les populations autochtones sont parmi les plus pauvres et les plus marginalisées de la planète. Ce sont elles aussi qui sont les plus tributaires, pour leur.

  5. Publications | Page 118 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La culture du pavot à opium : quelle politique pour l'Afghanistan ? La culture illicite du pavot à opium contribue à la subsistance de millions de paysans afghans, mais il se trouve qu'elle constitue également une source de revenus importants pour les bandes criminalisées.

  6. Publications | Page 24 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Cependant, il est couramment utilisé comme combustible, dans les régions rurales, pour faire cuire le pain dans un four traditionnel. Objectif du Vietnam : taille optimale pour les entreprises émergentes. La croissance impressionnante du Vietnam depuis les années 1990 lui a permis d'acquérir le statut de pays à revenu ...

  7. Publications | Page 162 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    africain. Il y a deux ans, le Centre de recherches pour le développement international a créé CIME, un programme de communication pour le développement, afin de témoigner de l'importance des interrelations entre la Communication à la base, l'.

  8. Publications | Page 101 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'action du CRDI L'adaptation aux changements climatiques. De nouvelles connaissances pour un avenir incertain. Bien avant que l'expression « réchauffement de la planète » ne fasse la manchette, le Centre de recherches pour le développement international (CRDI), organisme.

  9. Publications | Page 6 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Dans ce profil de 2014, les chercheurs du Tata Institute of Social Sciences Centre pour la politique urbaine et la gouvernance fournissent une base pour comprendre les nombreux visages de Mumbai et comment ses niveaux relativement bas de crime public masquent les nombreuses façons dont les résidents vivent la ...

  10. Mussel Shell Impaction in the Esophagus

    Directory of Open Access Journals (Sweden)

    Sunmin Kim

    2013-03-01

    Full Text Available Mussels are commonly used in cooking around the world. The mussel shell breaks more easily than other shells, and the edge of the broken mussel shell is sharp. Impaction can ultimately cause erosion, perforation and fistula. Aside from these complications, the pain can be very intense. Therefore, it is essential to verify and remove the shell as soon as possible. In this report we describe the process of diagnosing and treating mussel shell impaction in the esophagus. Physicians can overlook this unusual foreign body impaction due to lack of experience. When physicians encounter a patient with severe chest pain after a meal with mussels, mussel shell impaction should be considered when diagnosing and treating the patient.

  11. Furnace profile effects on glass shell formation

    International Nuclear Information System (INIS)

    O'Holleran, T.P.; Downs, R.L.; Homyk, B.D.

    1981-01-01

    In the course of blowing glass shells in a furnace drop tower it has been observed that furnace temperature profile affects shell aspect ratio. Wall uniformity appears less sensitive to temperature profile as long as some minimum-time/temperature history is achieved for a given glass composition. Quantitative results will be reported from experiments wherein the furnace temperature profile is systematically varied and the resultant shells are statistically analyzed for aspect ratio and wall uniformity

  12. Drexel University Shell Model (DUSM) algorithm

    Science.gov (United States)

    Valliéres, Michel; Novoselsky, Akiva

    1994-03-01

    This lecture is devoted to the Drexel University Shell Model (DUSM) code; this is a new shell-model code based on a separation of the various subspaces in which the single particle wavefunctions are defined. This is achieved via extensive use of permutation group concepts and a redefinition of the Coeficients of Fractional Parentage (CFP) to include permutation labels. This leads to a modern and efficient approach to nuclear shell-model.

  13. Drexel University Shell Model (DUSM) algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Vallieres, M. (Drexel Univ., Philadelphia, PA (United States). Dept. of Physics and Atmospheric Science); Novoselsky, A. (Hebrew Univ., Jerusalem (Israel). Dept. of Physics)

    1994-03-28

    This lecture is devoted to the Drexel University Shell Model (DUSM) code; this is a new shell-model code based on a separation of the various subspaces in which the single particle wavefunctions are defined. This is achieved via extensive use of permutation group concepts and a redefinition of the Coeficients of Fractional Parentage (CEP) to include permutation labels. This leads to a modern and efficient approach to nuclear shell-model. (orig.)

  14. A study of the properties of core/shell/shell Ag/FeCo/Ag nanoparticles

    Science.gov (United States)

    Kamzin, A. S.; Takahashi, M.; Maenosono, S.; Valiullin, A. A.

    2017-10-01

    The properties of heterophase core/shell/shell Ag/FeCo/Ag nanoparticles synthesized via a plasma method that are promising for biological applications are studied. As is established, the core/shell/shell Ag/FeCo/Ag nanoparticles exhibit a superparamagnetic state at room temperature that allows one to manage the hyperthermia process. The magnetic characteristics of core/shell/shell Ag/FeCo/Ag nanoparticles are interpreted by assuming partial oxidation of the surface layer of a ferromagnetic FeCo shell and formation of the antiferromagnetic CoxFe1-xO layer on the FeCo surface. The interaction between the surface antiferromagnetic CoxFe1-xO layer and the ferromagnetic FeCo shell causes the emergence of the exchange bias in Ag/FeCo/Ag nanoparticles.

  15. Multiple-shell ZnSe core-shell spheres and their improved photocatalytic activity.

    Science.gov (United States)

    Zhao, Lijuan; Sun, Chengcheng; Tian, Gang; Pang, Qi

    2017-09-15

    Multiple-shell ZnSe core-shell microspheres were synthesized on a large scale by a facile solvothermal method in ethylene glycol (EG) with ethylene diamine tetraacetic acid (EDTA) assisted. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-vis absorption spectroscopy and photoluminescence (PL) were used to characterize the structures and optical properties of these core-shell spheres with multiple shells. XRD and SEM analyses show that the as-grown ZnSe samples are zinc-blende core-shell structures with multiple shells. The possible growth mechanism is investigated. The results of photocatalysis of methyl red (MR) indicate that the multiple-shell ZnSe core-shell microspheres possess remarkable photocatalytic activity. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Hydrate Shell Growth Measured Using NMR.

    Science.gov (United States)

    Haber, Agnes; Akhfash, Masoumeh; Loh, Charles K; Aman, Zachary M; Fridjonsson, Einar O; May, Eric F; Johns, Michael L

    2015-08-18

    Benchtop nuclear magnetic resonance (NMR) pulsed field gradient (PFG) and relaxation measurements were used to monitor the clathrate hydrate shell growth occurring in water droplets dispersed in a continuous cyclopentane phase. These techniques allowed the growth of hydrate inside the opaque exterior shell to be monitored and, hence, information about the evolution of the shell's morphology to be deduced. NMR relaxation measurements were primarily used to monitor the hydrate shell growth kinetics, while PFG NMR diffusion experiments were used to determine the nominal droplet size distribution (DSD) of the unconverted water inside the shell core. A comparison of mean droplet sizes obtained directly via PFG NMR and independently deduced from relaxation measurements showed that the assumption of the shell model-a perfect spherical core of unconverted water-for these hydrate droplet systems is correct, but only after approximately 24 h of shell growth. Initially, hydrate growth is faster and heat-transfer-limited, leading to porous shells with surface areas larger than that of spheres with equivalent volumes. Subsequently, the hydrate growth rate becomes mass-transfer-limited, and the shells become thicker, spherical, and less porous.

  17. Celestial mechanics of planet shells

    Science.gov (United States)

    Barkin, Yu V.; Vilke, V. G.

    2004-06-01

    The motion of a planet consisting of an external shell (mantle) and a core (rigid body), which are connected by a visco-elastic layer and mutually gravitationally interact with each other and with an external celestial body (considered as a material point), is studied (Barkin, 1999, 2002a,b; Vilke, 2004). Relative motions of the core and mantle are studied on the assumption that the centres of mass of the planet and external body move on unperturbed Keplerian orbits around the general centre of mass of the system. The core and mantle of the planet have axial symmetry and have different principal moments of inertia. The differential action of the external body on the core and mantle cause the periodic relative displacements of their centres of mass and their relative turns. An approximate solution of the problem was obtained on the basis of the linearization, averaging and small-parameter methods. The obtained analytical results are applied to the study of the possible relative displacements of the core and mantle of the Earth under the gravitational action of the Moon. For the suggested two-body Earth model and in the simple case of a circular (model) lunar orbit the new phenomenon of periodic translatory-rotary oscillations of the core with a fortnightly period the mantle was observed. The more remarkable phenomenon is the cyclic rotation with the same period (13.7 days) of the core relative to the mantle with a ‘large’ amplitude of 152 m (at the core surface).The results obtained confirm the general concept described by Barkin (1999, 2002a,b) that induced relative shell oscillations can control and dictate the cyclic and secular processes of energization of the planets and satellites in definite rhythms and on different time scales.The results obtained mean that giant moments and forces produce energy which causes in particular deformations of the viscoelastic layer between planet shells. This process is realized with different intensities on different time

  18. Generic thin-shell gravastars

    Energy Technology Data Exchange (ETDEWEB)

    Martin-Moruno, Prado; Visser, Matt [School of Mathematics, Statistics, and Operations Research, Victoria University of Wellington, PO Box 600, Wellington 6140 (New Zealand); Garcia, Nadiezhda Montelongo [Departamento de Física, Centro de Investigación y Estudios avanzados del I.P.N., A.P. 14-700,07000 México, DF (Mexico); Lobo, Francisco S.N., E-mail: prado@msor.vuw.ac.nz, E-mail: nmontelongo@fis.cinvestav.mx, E-mail: flobo@cii.fc.ul.pt, E-mail: matt.visser@msor.vuw.ac.nz [Centro de Astronomia e Astrofísica da Universidade de Lisboa, Campo Grande, Edifício C8 1749-016 Lisboa (Portugal)

    2012-03-01

    We construct generic spherically symmetric thin-shell gravastars by using the cut-and-paste procedure. We take considerable effort to make the analysis as general and unified as practicable; investigating both the internal physics of the transition layer and its interaction with 'external forces' arising due to interactions between the transition layer and the bulk spacetime. Furthermore, we discuss both the dynamic and static situations. In particular, we consider 'bounded excursion' dynamical configurations, and probe the stability of static configurations. For gravastars there is always a particularly compelling configuration in which the surface energy density is zero, while surface tension is nonzero.

  19. Electron Shell as a Resonator

    International Nuclear Information System (INIS)

    Karpeshin, F. F.

    2002-01-01

    Main principles of the resonance effect arising in the electron shells in interaction of the nuclei with electromagnetic radiation are analyzed and presented in the historical aspect. Principles of NEET are considered from a more general position, as compared to how this is usually presented. Characteristic features of NEET and its reverse, TEEN, as internal conversion processes are analyzed, and ways are offered of inducing them by laser radiation. The ambivalent role of the Pauli exclusion principles in NEET and TEEN processes is investigated.

  20. Local shell-to-shell energy transfer via nonlocal interactions in fluid ...

    Indian Academy of Sciences (India)

    in a triad, and the energy exchanges between wave-number shells in incompressible fluid turbulence. The computation has been done using first-order perturbative field theory. In three dimensions, magnitude of triad interactions is large for nonlocal triads, and small for local triads. However, the shell-to-shell energy transfer ...

  1. Lead behavior in abalone shell

    Science.gov (United States)

    Hirao, Yoshimitsu; Matsumoto, Akikazu; Yamakawa, Hiroshi; Maeda, Masaru; Kimura, Kan

    1994-08-01

    In order to gain information about the behavior of heavy metals in biological assimilation processes in a marine food chain and to investigate the possibility that lead pollution in a marine environment can be estimated by measurement of a small number of key materials from such a food chain, muscle and shell were analyzed from abalone ( Haliotis) from a shallow water locality in a Japanese coastal region. Lead concentrations in muscle were about 26 ppb for abalone of approximately 3 years old and decreased systematically with increasing age of animals sampled, to about 3.3 ppb for a specimen approximately 8 years old. Lead concentrations in shell material gradually decreased also, from 150 ppb to 82 ppb in the oldest specimen. The decrease of concentration in tissues with increasing age indicates that a mechanism for exclusion of lead during tissue growth becomes more efficient with age. Along the food chain in which abalone is the final stage, lead was enriched at the first stage, from seawater to algae, by a factor of 100. Lead was diminished at all subsequent stages of the chain. Tissue of artificially cultured abalone had four times higher lead values compared to abalone grown in natural conditions, and this appears to reflect the fact that lead concentration was three times higher in seawater in the cultured environment.

  2. De meilleurs emplois pour l'Asie | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2 mars 2018 ... D'est en ouest, les économies de l'Asie se transforment rapidement, créant des emplois pour une population croissante de jeunes travailleurs. Cependant, qu'en est-il des conditions de travail ? Une recherche financée par le CRDI recueille des données probantes qui démontrent que de meilleures ...

  3. Continuous temperature measurements on the pouring stand for casting moulds

    Directory of Open Access Journals (Sweden)

    W. Leśniewski

    2008-04-01

    Full Text Available The results of temperature measurements of liquid iron alloys obtained by means of the pyrometer, PDR-1800 series, are presented in the paper. The measurements were performed in conditions determined by the kind of a pouring device. The results obtained for bottom-tap ladles were supplemented by laboratory measurements. These results allow explaining significant differences in the results of temperature measurements performed in pouring ladles by means of the pyrometric method and immersible thermocouple, which - in turn - improves assessment of metal thermal parameters in pouring devices.

  4. Data Center: infrastructure pour la ville

    OpenAIRE

    Sachs, Mikaël

    2016-01-01

    A l'aube d'une génération 100 % numérique, notre production, notre consommation ainsi que le traitement de nos données digitales augmentent de façon exponentielle. Le data center, milieu tempéré et sécurisé pour les machines, est le cœur de cette nouvelle ère. L'information dématérialisée nécessite une infrastructure précise et complexe. Gardien des cultures mouvantes et insaisissables, le data center peut être perçu comme un univers public parallèle à la ville, son insertion dans le milieu u...

  5. Suivi de route pour un robot voilier

    OpenAIRE

    Jaulin, Luc; Le Bars, Fabrice; Clement, Benoît; Gallou, Yvon; Menage, Olivier; REYNET, Olivier; Sliwka, Jan; Zerr, Benoît

    2012-01-01

    International audience; Un robot voilier est un système fortement nonlinéaire qui pourtant se commande relativement facilement. En effet, sa conception mécanique découle d'une évolution pragmatique sur plusieurs milliers d'années avec pour double objectif : celui d'une machine rapide et celui d'avoir un véhicule facile à commander. Cet article propose une stratégie de régulation d'un robot voilier inspirée de celle utilisée par les navigateurs. Le régulateur qui en résulte est simple, avec pe...

  6. A lunguistica pour ses quarante ans

    Directory of Open Access Journals (Sweden)

    Ludvik Horvat Le Doyen

    2000-12-01

    Full Text Available En tant que doyen de la Faculté des Lettres de l'Universite de Ljubljana, j'ai l'honneur d'introduire le volume qui celebre les quarante ans de publication de cette revue linguistique. La parution de la revue conçua à l' origine comme supplàment pour la linguistique non slave de la revue Slavistična revija (dont la renommée était déjà affirmée, eut lieu en 1958. Ses inspirateurs, ses fondateurs et ses premiers directeurs, auxquels nous gardons une profonde reconnaissance, furent l'italianiste Stanko Škerlj et le latiniste Milan Grošelj, professeurs de notre Faculté. Des sa quatrieme année ce modeste supplement devint revue autonome, telle que nous la connaissons aujourd'hui.

  7. Shell effects in the nuclear deformation energy

    International Nuclear Information System (INIS)

    Ross, C.K.

    1973-01-01

    A new approach to shell effects in the Strutinsky method for calculating nuclear deformation energy is evaluated and the suggestion of non-conservation of angular momentum in the same method is resolved. Shell effects on the deformation energy in rotational bands of deformed nuclei are discussed. (B.F.G.)

  8. Localized versus shell-model-like clusters

    Energy Technology Data Exchange (ETDEWEB)

    Cseh, J.; Algora, A. [Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen, Pf. 51, 4001 Hungary (Hungary); Darai, J. [Institute of Experimental Physics, University of Debrecen, Debrecen, Bem ter 18/A, 4026 Hungary (Hungary); Yepez M, H. [Universidad Autonoma de la Ciudad de Mexico, Prolongacion San Isidro 151, Col. San Lorenzo Tezonco, 09790 Mexico D. F. (Mexico); Hess, P. O. [Instituto de Ciencias Nucleares, UNAM, Apartado Postal 70-543, 04510 Mexico D. F. (Mexico)]. e-mail: cseh@atomki.hu

    2008-12-15

    In light of the relation of the shell model and the cluster model, the concepts of localized and shell-model-like clusters are discussed. They are interpreted as different phases of clusterization, which may be characterized by quasi-dynamical symmetries, and are connected by a phase-transition. (Author)

  9. Statistical Mechanics of Thin Spherical Shells

    Directory of Open Access Journals (Sweden)

    Andrej Košmrlj

    2017-01-01

    Full Text Available We explore how thermal fluctuations affect the mechanics of thin amorphous spherical shells. In flat membranes with a shear modulus, thermal fluctuations increase the bending rigidity and reduce the in-plane elastic moduli in a scale-dependent fashion. This is still true for spherical shells. However, the additional coupling between the shell curvature, the local in-plane stretching modes, and the local out-of-plane undulations leads to novel phenomena. In spherical shells, thermal fluctuations produce a radius-dependent negative effective surface tension, equivalent to applying an inward external pressure. By adapting renormalization group calculations to allow for a spherical background curvature, we show that while small spherical shells are stable, sufficiently large shells are crushed by this thermally generated “pressure.” Such shells can be stabilized by an outward osmotic pressure, but the effective shell size grows nonlinearly with increasing outward pressure, with the same universal power-law exponent that characterizes the response of fluctuating flat membranes to a uniform tension.

  10. Fabrication of Foam Shells for ICF Experiments

    Science.gov (United States)

    Czechowicz, D. G.; Acenas, O.; Flowers, J. S.; Nikroo, A.; Paguio, R. R.; Schroen, D. G.; Streit, J.; Takagi, M.

    2004-11-01

    The General Atomics/Schafer team has developed processes to fabricate foam shells targets suitable for ICF experiments. The two most common chemical systems used to produce foam shells have been resorcinol-formaldehyde (R/F) aerogel and divinylbenzene (DVB). Spherical targets have been made in the form of shells and beads having diameters ranging from approximately 0.5 mm to 4.0 mm, and having densities from approximately 100 mg/cc to 250 mg/cc. The work on R/F foam shells has been concentrated on 1) shell fabrication process improvement to obtain high yields ( ˜25%) and 2) depositing a reliable permeation barrier to provide shells for ongoing direct drive experiments at LLE. Development of divinylbenzene foam shells has been mainly directed towards Inertial Fusion Energy applications (at densities as low as 30 mg/cc) and recently for shells for experiments at LLE. Details of the relevant metrology and properties of these foams as well as the range of targets currently available will be discussed.

  11. Thick-shell nanocrystal quantum dots

    Science.gov (United States)

    Hollingsworth, Jennifer A [Los Alamos, NM; Chen, Yongfen [Eugene, OR; Klimov, Victor I [Los Alamos, NM; Htoon, Han [Los Alamos, NM; Vela, Javier [Los Alamos, NM

    2011-05-03

    Colloidal nanocrystal quantum dots comprising an inner core having an average diameter of at least 1.5 nm and an outer shell, where said outer shell comprises multiple monolayers, wherein at least 30% of the quantum dots have an on-time fraction of 0.80 or greater under continuous excitation conditions for a period of time of at least 10 minutes.

  12. Ancient shell industry at Bet Dwarka island

    Digital Repository Service at National Institute of Oceanography (India)

    Gaur, A.S.; Sundaresh; Patankar, V.

    Almost every archaeological site in the Indian subcontinent has the remains of shells. It had been recognized as a major industry during the Indus Valley Civilization, dating back to the mid-Holocene. The most important shell used in the past...

  13. Statistical mechanics of microscopically thin thermalized shells

    Science.gov (United States)

    Kosmrlj, Andrej

    Recent explosion in fabrication of microscopically thin free standing structures made from graphene and other two-dimensional materials has led to a renewed interest in the mechanics of such structures in presence of thermal fluctuations. Since late 1980s it has been known that for flat solid sheets thermal fluctuations effectively increase the bending rigidity and reduce the bulk and shear moduli in a scale-dependent fashion. However, much is still unknown about the mechanics of thermalized flat sheets of complex geometries and about the mechanics of thermalized shells with non-zero background curvature. In this talk I will present recent development in the mechanics of thermalized ribbons, spherical shells and cylindrical tubes. Long ribbons are found to behave like hybrids between flat sheets with renormalized elastic constants and semi-flexible polymers, and these results can be used to predict the mechanics of graphene kirigami structures. Contrary to the anticipated behavior for ribbons, the non-zero background curvature of shells leads to remarkable novel phenomena. In shells, thermal fluctuations effectively generate negative surface tension, which can significantly reduce the critical buckling pressure for spherical shells and the critical axial load for cylindrical tubes. For large shells this thermally generated load becomes big enough to spontaneously crush spherical shells and cylindrical tubes even in the absence of external loads. I will comment on the relevance for crushing of microscopic shells (viral capsids, bacteria, microcapsules) due to osmotic shocks and for crushing of nanotubes.

  14. Intershell correlations in photoionization of outer shells

    International Nuclear Information System (INIS)

    Amusia, M.Ya.; Chernysheva, L.V.; Drukarev, E.G.

    2016-01-01

    We demonstrate that the cross sections for photoionization of the outer shells are noticeably modified at the photon energies close to the thresholds of ionization of the inner shells due to correlations with the latter. The correlations may lead to increase or to decrease of the cross sections just above the ionization thresholds.

  15. Intershell correlations in photoionization of outer shells

    Energy Technology Data Exchange (ETDEWEB)

    Amusia, M.Ya. [The Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem 91904 (Israel); A.F. Ioffe Physical-Technical Institute, St. Petersburg 194021 (Russian Federation); Chernysheva, L.V. [A.F. Ioffe Physical-Technical Institute, St. Petersburg 194021 (Russian Federation); Drukarev, E.G. [National Research Center “Kurchatov Institute”, Konstantinov Petersburg Nuclear Physics Institute, St. Petersburg 188300 (Russian Federation)

    2016-02-15

    We demonstrate that the cross sections for photoionization of the outer shells are noticeably modified at the photon energies close to the thresholds of ionization of the inner shells due to correlations with the latter. The correlations may lead to increase or to decrease of the cross sections just above the ionization thresholds.

  16. Microsoft Exchange Server PowerShell cookbook

    CERN Document Server

    Andersson, Jonas

    2015-01-01

    This book is for messaging professionals who want to build real-world scripts with Windows PowerShell 5 and the Exchange Management Shell. If you are a network or systems administrator responsible for managing and maintaining Exchange Server 2013, you will find this highly useful.

  17. Strength Calculation of Locally Loaded Orthotropic Shells

    Directory of Open Access Journals (Sweden)

    Yu. I. Vinogradov

    2015-01-01

    Full Text Available The article studies laminated orthotropic cylindrical, conic, spherical, and toroidal shells, which are often locally loaded in the aircraft designs over small areas of their surfaces.The aim of this work is to determine stress concentration in shells versus structure of orthotropic composite material, shell form and parameters, forms of loading areas, which borders do not coincide with lines of main curvatures of shells. For this purpose, an analytical computing algorithm to estimate strength of shells in terms of stress is developed. It enables us to have solution results of the boundary value problem with a controlled error. To solve differential equations an analytical method is used. An algorithm of the boundary value problem solution is multiplicative.The main results of researches are graphs of stress concentration in the orthotropic shells versus their parameters and areas of loading lineated by circles and ellipses.Among the other works aimed at determination of stress concentration in shells, the place of this one is defined by the analytical solution of applied problems for strength estimation in terms of shell stresses of classical forms.The developed effective analytical algorithm to solve the boundary value problem and received results are useful in research and development.

  18. Collapsing spherical null shells in general relativity

    Directory of Open Access Journals (Sweden)

    S Khakshournia

    2011-03-01

    Full Text Available In this work, the gravitational collapse of a spherically symmetric null shell with the flat interior and a charged Vaidya exterior spacetimes is studied. There is no gravitational impulsive wave present on the null hypersurface which is shear-free and contracting. It follows that there is a critical radius at which the shell bounces and starts expanding.

  19. Engineered Magnetic Core-Shell Structures.

    Science.gov (United States)

    Alavi Nikje, Mir Mohammad; Vakili, Maryam

    2015-01-01

    In recent years, engineered magnetic core-shell structures are playing an important role in the wide range of various applications. These magnetic core-shell structures have attracted considerable attention because of their unique properties and various applications. Also, the synthesis of engineered magnetic core-shell structures has attracted practical interest because of potential applications in areas such as ferrofluids, medical imaging, drug targeting and delivery, cancer therapy, separations, and catalysis. So far a large number of engineered magnetic core-shell structures have been successfully synthesized. This review article focuses on the recent progress in synthesis and characterization of engineered magnetic core-shell structures. Also, this review gives a brief description of the various application of these structures. It is hoped that this review will play some small part in helping future developments in important field.

  20. Structural shell analysis understanding and application

    CERN Document Server

    Blaauwendraad, Johan

    2014-01-01

    The mathematical description of the properties of a shell is much more elaborate than those of beam and plate structures. Therefore many engineers and architects are unacquainted with aspects of shell behaviour and design, and are not familiar with sufficiently reliable shell theories for the different shell types as derived in the middle of the 20th century. Rather than contributing to theory development, this university textbook focuses on architectural and civil engineering schools. Of course, practising professionals will profit from it as well. The book deals with thin elastic shells, in particular with cylindrical, conical and spherical types, and with elliptic and hyperbolic paraboloids. The focus is on roofs, chimneys, pressure vessels and storage tanks. Special attention is paid to edge bending disturbance zones, which is indispensable knowledge in FE meshing. A substantial part of the book results from research efforts in the mid 20th century at Delft University of Technology. As such, it is a valua...

  1. Obtainment of calcium carbonate from mussels shell

    International Nuclear Information System (INIS)

    Hamester, M.R.R.; Becker, D.

    2010-01-01

    The mussels and oyster shell are discarded at environment, and this accumulation is causing negative consequences to ecosystem. Calcium carbonate is main constituent of the shell chemical composition. Aiming to reduce environmental aggression and generate income to shellfish producer, there was the possibility of using these shells as an alternative to commercial calcium carbonate. For this physics, chemicals and thermal properties were evaluated, using X-ray fluorescence, thermogravimetric analysis, size distribution, abrasiveness and scanning electronic microscopy. The results indicate that mussels shells have an initial degradation temperature higher than commercial calcium carbonate e same lost weight behavior and 95% of shell chemical composition is calcium carbonate. The sample size distribution was influenced by grinding condition and time as well as its abrasiveness. (author)

  2. Variability in shell models of GRBs

    Science.gov (United States)

    Sumner, M. C.; Fenimore, E. E.

    1997-01-01

    Many cosmological models of gamma-ray bursts (GRBs) assume that a single relativistic shell carries kinetic energy away from the source and later converts it into gamma rays, perhaps by interactions with the interstellar medium or by internal shocks within the shell. Although such models are able to reproduce general trends in GRB time histories, it is difficult to reproduce the high degree of variability often seen in GRBs. The authors investigate methods of achieving this variability using a simplified external shock model. Since the model emphasizes geometric and statistical considerations, rather than the detailed physics of the shell, it is applicable to any theory that relies on relativistic shells. They find that the variability in GRBs gives strong clues to the efficiency with which the shell converts its kinetic energy into gamma rays.

  3. Évaluation organisationnelle | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    évaluation. Charles Lusthaus, Marie-Hélène Adrien, Gary Anderson et Fred Carden (CRDI 1999). ÉVALUATION INSTITUTIONNELLE: Cadre pour le renforcement des organisations partenaires du CRDI. Charles Lusthaus, Gary ...

  4. Modelisation des effets physico-techniques pour la conception des ...

    African Journals Online (AJOL)

    automatisation dans les installations industrielles a besoin d'une régulation automatique des commandes des processus technologiques pour lesquelles certaines contraintes sont à relever compte tenu des exigences des innovations scientifiques de ...

  5. Inde | Page 80 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    FOOD India), a commencé à se demander comment faire pour mettre les ... experimentation, and research related to information and communication technologies for development (ICTs), employment generation, and other aspects of sustainable.

  6. Stability of accelerated metal shells

    International Nuclear Information System (INIS)

    Tahsiri, H.

    1976-01-01

    A systematic treatment has been developed for the Rayleigh-Taylor instability of an accelerated liner. It is applicable to one-dimensional models either compressible or incompressible. With this model several points have been clarified. For an incompressible liner model, the Rayleigh-Taylor instability will have about five e-folding periods and the usual growth rate is independent of the current distribution or current rise time. Adequate stability will therefore depend on the magnitude of the initial perturbations or the precision of the initial liner and the thickness over which the shell is accelerated. However, for a compressible model, theory predicts that the current rise time is important and the Rayleigh-Taylor instability is suppressed if the current rise time is less than the shock transit time

  7. Bioavailability and Variability of Cd, Pb, Zn, and Cu Pollution in Soft Tissues and Shell of Saccostrea cucullata Collected from the Coast of Qeshm Island, Persian Gulf, Iran

    Directory of Open Access Journals (Sweden)

    Ali Kazemi

    2016-07-01

    Full Text Available Background: Marine pollution is a global environmental problem that its monitoring by ideal biomonitors is of great importance. Marine organisms, especially mussels, have the ability to accumulate metals from the environment; they can be considered as a biomonitoring agent. Methods: In this study, concentrations of heavy metals were measured in Saccostrea cucullata collected from seven sites on Qeshm Island's Coast. To achieve a digesting sample, each soft tissue was obtained and each of the shell homogeneous powders, 0.8 g and 1 g, respectively, were mixed with 10 mL HNO3 (69% and poured into a PTFE digestion vessel. The prepared samples were evaluated for Cd, Cu, and Zn by using a flame AAS Model 67OG and for Pb by using a graphite furnace AAS. Results: The distributions of metals between soft tissues and shells were compared in each sampling site. For seven sites, Cd, Zn, and Cu levels in soft tissues were higher than in the shells, but Pb level was higher in the shells than in the soft tissues. In addition, the results indicated the coefficient of variation (CV in the soft tissues was lower than the shells for Cd, and in the shells lower than the soft tissues for Pb, whereas the CV values were different in both the soft tissues and shells for Zn and Cu. Conclusion: The results of this study support using these materials in S. cucullata for biomonitoring. Shells are appropriate for monitoring Pb contamination, and the soft tissues are more apt for monitoring Cd, Zn, and Cu contamination.

  8. Nepal : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Renforcement de la résilience des collectivités de montagne : reconstruction après le séisme à Dhungentar, au Népal ... Ce projet mettra à l'essai diverses innovations en matière d'agriculture en terrasses et offrira des stratégies aux ONG pour aider 100 000 entrepreneurs népalais en créant une nouvelle entreprise pour ...

  9. Publications | Page 54 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Nous communiquons les résultats des recherches que nous finançons et offrons du matériel de formation gratuit pour venir en aide aux chercheurs et aux institutions. ... Résultats. 531 - 540 de 2332. En Afrique, la croissance sera-t-elle synonyme d'emplois pour les jeunes ? L'Afrique est le continent du monde dont la ...

  10. Publications | Page 166 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Mainstreaming Informal and Gender in Poverty Reduction : A Handbook for Policy-makers and other Stakeholders ... En élargissant l'ensemble d'indicateurs existant pour y inclure le stress, l'anxiété et la violence reliés à l'appartenance à un sexe, ce livre présente un nouveau cadre pour la recherche sur les questions de ...

  11. Publications | Page 31 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Principes de responsabilité et de solidarité pour un accès financier équitable aux soins de santé : le cas des travailleurs de l'informel urbain du Cameroun en situation de ... D'est en ouest, les économies de l'Asie se transforment rapidement, créant des emplois pour une population croissante de jeunes travailleurs.

  12. Livres | Page 21 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Elles permettent de communiquer les résultats de nos études à d'autres chercheurs, décideurs politiques et communautés dans le monde. ... En élargissant l'ensemble d'indicateurs existant pour y inclure le stress, l'anxiété et la violence reliés à l'appartenance à un sexe, ce livre présente un nouveau cadre pour la ...

  13. Publications | Page 67 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Nous communiquons les résultats des recherches que nous finançons et offrons du matériel de formation gratuit pour venir en aide aux chercheurs et aux ... de sa capacité de générer, d'adapter et d'utiliser des connaissances scientifiques pour satisfaire aux besoins locaux en matière de santé et de développement. Or, les ...

  14. Descriptif 2006-2011 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le 28 juin 2006, le domaine de programme Innovation, politique et science (IPS) a présenté au Conseil des gouverneurs du CRDI un plan stratégique pour orienter la phase initiale (2006 2011) des recherches menées en vertu de sa toute première initiative de programme, qui a pour nom Innovation, technologie et société ...

  15. Livres | Page 34 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Auteur(s) : Stephen C. Lonergan et David B. Brooks. Maison(s) d'édition : CRDI. ISBN: Épuisé. Couverture du livre Un brevet pour la vie : La propriété intellectuelle et ses effets sur. Un brevet pour la vie : La propriété intellectuelle et ses effets sur le commerce, la biodiversité et le monde rural. L'aboutissement récent de la ...

  16. ethiopia : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le but de ce projet consiste à améliorer la compréhension des complexités du mariage d'enfants et de la parentalité pour éclairer les politiques et les programmes. Sujet: Gender. Région: Ethiopia, Peru, Zambia. Programme: Gouvernance et justice. Financement total : CA$ 1,120,200.00. Alliance statistique pour les faits ...

  17. Publications | Page 127 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le Vietnam a entrepris une ambitieuse transition d'un caractère singulier : il a tenté de transformer l'économie du pays par le biais de la libéralisation du marché, sans modifier pour autant sa structure politique centralisée. L'... Recherche pour le développement — Cambodge. Après avoir été dévasté par la guerre civile et ...

  18. Nouveaux centres de cyberpolitique pour les pays du Sud | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    13 avr. 2018 ... L'appel ouvert avait pour but de cibler les organismes indépendants voués à la recherche sur les politiques qui s'appuient sur la recherche pour éclairer et influencer les politiques nationales dans les domaines des droits numériques, de la cybersécurité et des politiques d'innovation. Parmi les 59 ...

  19. Free vibration analysis of delaminated composite shells using different shell theories

    International Nuclear Information System (INIS)

    Nanda, Namita; Sahu, S.K.

    2012-01-01

    Free vibration response of laminated composite shells with delamination is presented using the finite element method based on first order shear deformation theory. The shell theory used is the extension of dynamic, shear deformable theory according to the Sanders' first approximation for doubly curved shells, which can be reduced to Love's and Donnell's theories by means of tracers. An eight-noded C 0 continuity, isoparametric quadrilateral element with five degrees of freedom per node is used in the formulation. For modeling the delamination, multipoint constraint algorithm is incorporated in the finite element code. The natural frequencies of the delaminated cylindrical (CYL), spherical (SPH) and hyperbolic paraboloid (HYP) shells are determined by using the above mentioned shell theories, namely Sanders', Love's, and Donnell's. The validity of the present approach is established by comparing the authors' results with those available in the literature. Additional studies on free vibration response of CYL, SPH and HYP shells are conducted to assess the effects of delamination size and number of layers considering all three shell theories. It is shown that shell theories according to Sanders and Love always predict practically identical frequencies. Donnell's theory gives reliable results only for shallow shells. Moreover, the natural frequency is found to be very sensitive to delamination size and number of layers in the shell.

  20. Axisymmetric vibrations of thick shells of revolution

    International Nuclear Information System (INIS)

    Suzuki, Katsuyoshi; Kosawada, Tadashi; Takahashi, Shin

    1983-01-01

    Axisymmetric shells of revolution are used for chemical plants, nuclear power plants, aircrafts, structures and so on, and the elucidation of their free vibration is important for the design. In this study, the axisymmetric vibration of a barrel-shaped shell was analyzed by the modified thick shell theory. The Lagrangian during one period of the vibration of a shell of revolution was determined, and from its stopping condition, the vibration equations and the boundary conditions were derived. The vibration equations were analyzed strictly by using the series solution. Moreover, the basic equations for the strain of a shell and others were based on those of Love. As the examples of numerical calculation, the natural frequency and vibration mode of the symmetrical shells of revolution fixed at both ends and supported at both ends were determined, and their characteristics were clarified. By comparing the results of this study with the results by thin shell theory, the effects of shearing deformation and rotary inertia on the natural frequency and vibration mode were clarified. The theoretical analysis and the numerical calculation are described. The effects of shearing deformation and rotary inertia on the natural frequency became larger in the higher order vibration. The vibration mode did not much change in both theories. (Kako, I.)

  1. Atomic mass formula with linear shell terms

    International Nuclear Information System (INIS)

    Uno, Masahiro; Yamada, Masami; Ando, Yoshihira; Tachibana, Takahiro.

    1981-01-01

    An atomic mass formula is constructed in the form of a sum of gross terms and empirical linear shell terms. Values of the shell parameters are determined after the statistical method of Uno and Yamada, Which is characterized by inclusion of the error inherent in the mass formula. The resulting formula reproduces the input masses with the standard deviation of 393 keV. A prescription is given for estimating errors of calculated masses. The mass formula is compared with recent experimental data of Rb, Cs and Fr isotopes, which are not included in the input data, and also with the constant-shell-term formula of Uno and Yamada. (author)

  2. Bending stresses in Facetted Glass Shells

    DEFF Research Database (Denmark)

    Bagger, Anne; Jönsson, Jeppe; Almegaard, Henrik

    2008-01-01

    A shell structure of glass combines a highly effective structural principle with a material of optimal permeability to light. A facetted shell structure has a piecewise plane geometry, and together the facets form an approximation to a curved surface. A distributed load on a plane-based facetted...... structure will locally cause bending moments in the loaded facets. The bending stresses are dependent on the stiffness of the joints. Approximate solutions are developed to estimate the magnitude of the bending stresses. A FE-model of a facetted glass shell structure is used to validate the expressions...

  3. Thin shells joining local cosmic string geometries

    Energy Technology Data Exchange (ETDEWEB)

    Eiroa, Ernesto F. [Universidad de Buenos Aires, Ciudad Universitaria Pabellon I, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Buenos Aires (Argentina); Instituto de Astronomia y Fisica del Espacio (IAFE, CONICET-UBA), Buenos Aires (Argentina); Rubin de Celis, Emilio; Simeone, Claudio [Universidad de Buenos Aires, Ciudad Universitaria Pabellon I, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Buenos Aires (Argentina); Ciudad Universitaria Pabellon I, IFIBA-CONICET, Buenos Aires (Argentina)

    2016-10-15

    In this article we present a theoretical construction of spacetimes with a thin shell that joins two different local cosmic string geometries. We study two types of global manifolds, one representing spacetimes with a thin shell surrounding a cosmic string or an empty region with Minkowski metric, and the other corresponding to wormholes which are not symmetric across the throat located at the shell. We analyze the stability of the static configurations under perturbations preserving the cylindrical symmetry. For both types of geometries we find that the static configurations can be stable for suitable values of the parameters. (orig.)

  4. THE PYTHON SHELL FOR THE ORBIT CODE

    Energy Technology Data Exchange (ETDEWEB)

    Shishlo, Andrei P [ORNL; Gorlov, Timofey V [ORNL; Holmes, Jeffrey A [ORNL

    2009-01-01

    A development of a Python driver shell for the ORBIT simulation code is presented. The original ORBIT code uses the SuperCode shell to organize accelerator-related simulations. It is outdated, unsupported, and it is an obstacle to future code development. The necessity and consequences of replacing the old shell language are discussed. A set of core modules and extensions that are currently in PyORBIT are presented. They include particle containers, parsers for MAD and SAD lattice files, a Python wrapper for MPI libraries, space charge calculators, TEAPOT trackers, and a laser stripping extension module.

  5. A theory of latticed plates and shells

    CERN Document Server

    Pshenichnon, Gi

    1993-01-01

    The book presents the theory of latticed shells as continual systems and describes its applications. It analyses the problems of statics, stability and dynamics. Generally, a classical rod deformation theory is applied. However, in some instances, more precise theories which particularly consider geometrical and physical nonlinearity are employed. A new effective method for solving general boundary value problems and its application for numerical and analytical solutions of mathematical physics and reticulated shell theory problems is described. A new method of solving the shell theory's nonli

  6. Analysis of anisotropic shells containing flowing fluid

    International Nuclear Information System (INIS)

    Lakis, A.A.

    1983-01-01

    A general theory for the dynamic analysis of anisotropic thin cylindrical shells containing flowing fluid is presented. The shell may be uniform or non-uniform, provided it is geometrically axially symmetric. This is a finite- element theory, using cylindrical finite elements, but the displacement functions are determined by using classical shell theory. A new solution of the wave equation of the liquid finite element leads to an expression of the fluid pressure, p, as a function of the nodal displacements of the element and three operative forces (inertia, centrifugal and Coriolis) of the moving fluid. (Author) [pt

  7. Decodeurs rapides pour codes topologiques quantiques

    Science.gov (United States)

    Duclos-Cianci, Guillaume

    L'encodage topologique de l'information quantique a attire beaucoup d'attention, car c'est un modele qui semble propice a resister aux erreurs locales. Tout d'abord, le modele du calcul topologique est base sur la statistique anyonique non-Abelienne universelle et sur son controle. Des anyons indesirables peuvent apparaitre soudainement, en raison de fluctuations thermiques ou de processus virtuels. La presence de ces anyons peut corrompre l'information encodee, il est necessaire de les eliminer: la correction consiste a fusionner les defauts tout en preservant la topologie du systeme. Ensuite, dans le cas des codes topologiques, on doit aussi proteger l'information encodee dans la topologie. En effet, dans ces systemes, on n'a acces qu'a une fraction de l'information decrivant l'erreur. Elle est recueillie par des mesures et peut etre interpretee en termes de particules. Ces defauts peuplent le code et doivent etre annihiles adequatement dans le but de preserver l'information encodee. Dans ce memoire, nous proposons un algorithme efficace, appele decodeur, pouvant etre utilise dans les deux contextes decrits ci-haut. Pour y parvenir, cet algorithme s'inspire de methodes de renormalisation et de propagation de croyance. Il est exponentiellement plus rapide que les methodes deja existantes, etant de complexite O (ℓ2 log ℓ) en serie et, si on parallelise, O (log ℓ) en temps, contre O (ℓ6) pour les autres decodeurs. Le temps etant le facteur limitant dans le probleme du decodage, cette caracteristique est primordiale. De plus, il tolere une plus grande amplitude de bruit que les methodes existantes; il possede un seuil de ˜ 16.5% sur le canal depolarisant surpassant le seuil deja etabli de ˜ 15.5%. Finalement, il est plus versatile. En effet, en etant limite au code de Kitaev, on ne savait pas decoder les codes topologiques de maniere generale (e.g. codes de couleur). Or, le decodeur propose dans ce memoire peut traiter la grande classe des codes

  8. Images du Mage, images pour le Mage

    Directory of Open Access Journals (Sweden)

    Daniel GREGORIO

    2007-01-01

    Full Text Available Les œuvres d’Alphonse X proposent diverses représentations du mage, qui en font, tour à tour, l’ennemi ou l’allié de la religion chrétienne. Il est vrai que parfois, comme le montre l’histoire de Simon le magicien, la pratique de la magie implique un commerce direct et néfaste avec les forces infernales. Néanmoins, les personnages de Merlin et des Rois Mages, tels qu’ils sont présentés par Alphonse X, démontrent que magie et religion peuvent cohabiter, à condition toutefois que le mage croit en la virginité de Marie et en l’Incarnation et que sa pratique magique soit bénéfique pour la communauté. Ce bénéfice requiert parfois la reconstruction de l’univers quotidien ; pour ce faire, le magicien doit savoir quand et comment utiliser des objets et des pentacles, qui lui permettront de soumettre les forces surnaturelles. Il doit donc posséder une connaissance approfondie du monde naturel et des esprits qui, conjuguée à sa foi religieuse, l’empêchera de tomber dans la démonolâtrie.Las obras alfonsíes proponen diversas aproximaciones al personaje del mago, generalmente considerado como un ser antagónico del hombre religioso. Es cierto que en algunas ocasiones, como ocurre con Simón el mago, la práctica de las artes mágicas significa un trato directo y nefasto con las fuerzas infernales. Sin embargo, personajes como Merlín o los Reyes Magos, tal y como los describe Alfonso X, subrayan una posible cohabitación entre magia y religión sin que la práctica de la una signifique la exclusión de la otra. Sólo hay que cumplir con dos condiciones : creer en la virginidad de María y que Dios se hizo hombre, y proporcionar a la comunidad un beneficio claro. Este beneficio requiere en ocasiones remodelar lo cotidiano, utilizando objetos y pentáculos, en circunstancias extremadamente determinadas, lo que implica un conocimiento exhaustivo tanto del mundo natural como del simbólico y de los espíritus. Es este

  9. Pour une ingénierie des Environnements Informatiques pour l'Apprentissage Humain

    OpenAIRE

    Tchounikine , Pierre

    2002-01-01

    Nous proposons dans cet article une réflexion sur la notion d'ingénierie des EIAH (Environnements Informatiques pour l'Apprentissage Humain). Nous posons tout d'abord une définition de l'ingénierie des EIAH : travaux visant à définir des éléments de méthodes et de techniques reproductibles et/ou réutilisables facilitant la mise en place (conception – réalisation – expérimentation – évaluation - diffusion) d'environnements de formation ou d'apprentissage (dans leur articulation avec les dispos...

  10. Comment agir pour raviver l'espoir ? Pour un traitement efficace du ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    28 févr. 2011 ... Dix pour cent de la population mondiale vit dans cette région qui affiche près de 70 % des cas d'infection par le VIH dans le monde et 90 % des décès causés par le sida. En 2005, on y a relevé environ 2,7 millions de nouveaux cas, ce qui porterait à 24,5 millions le nombre de personnes vivant avec le ...

  11. Oyster Shell Proteins Originate from Multiple Organs and Their Probable Transport Pathway to the Shell Formation Front

    Science.gov (United States)

    Zhu, Yabing; Du, Yishuai; Song, Xiaorui; Chen, Yuanxin; Huang, Ronglian; Que, Huayong; Fang, Xiaodong; Zhang, Guofan

    2013-01-01

    Mollusk shell is one kind of potential biomaterial, but its vague mineralization mechanism hinders its further application. Mollusk shell matrix proteins are important functional components that are embedded in the shell, which play important roles in shell formation. The proteome of the oyster shell had been determined based on the oyster genome sequence by our group and gives the chance for further deep study in this area. The classical model of shell formation posits that the shell proteins are mantle-secreted. But, in this study, we further analyzed the shell proteome data in combination with organ transcriptome data and we found that the shell proteins may be produced by multiple organs though the mantle is still the most important organ for shell formation. To identify the transport pathways of these shell proteins not in classical model of shell formation, we conducted a shell damage experiment and we determined the shell-related gene set to identify the possible transport pathways from multiple organs to the shell formation front. We also found that there may exist a remodeling mechanism in the process of shell formation. Based on these results along with some published results, we proposed a new immature model, which will help us think about the mechanism of shell formation in a different way. PMID:23840499

  12. Un ticket pour la liberté

    Directory of Open Access Journals (Sweden)

    Nabil Mouline

    2014-07-01

    Full Text Available Pour diverses raisons, l’industrie cinématographique égyptienne a connu des changements profonds au début des années 2000. L’une des conséquences les plus palpables a été la production de manière volontaire ou involontaire de films contestataires dans la mesure où ils essaient de remettre en cause le discours dominant et de lever le tabou sur plusieurs questions sociopolitiques. Cela a fait du produit filmique non seulement un document d’archive qui reflète l’état de la société mais également un outil efficace de soft influence et de mobilisation qui a participé à la création d’une communauté imaginée dont une partie est passée à l’action le 25 janvier 2011. C’est l’ambition de cet article que de lever le voile sur ce double rôle du cinéma entre 2001 et 2010 en s’appuyant sur un large échantillon de films à grand succès.

  13. Short Communication: Comparative effect of snail shell, limestone ...

    African Journals Online (AJOL)

    Short Communication: Comparative effect of snail shell, limestone and oyster shell as sources of dietary calcium on performance and egg quality characteristics of laying. ... egg production, internal and external qualities of eggs of hens. The 6-week ... Key words: Laying hens, oyster shell, limestone, snail shell, egg quality ...

  14. 41 CFR 102-85.120 - What is shell Rent?

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What is shell Rent? 102... GSA SPACE Rent Charges § 102-85.120 What is shell Rent? Shell Rent is that portion of GSA Rent charged for the building envelope and land. (See § 102-85.35 for the definition of building shell.) ...

  15. Design aids for fixed support reinforced concrete cylindrical shells ...

    African Journals Online (AJOL)

    Shells are objects considered as materialization of the curved surface. Despite structural advantages and architectural aesthetics possessed by shells, relative degree of unacquaintance with shell behavior and design is high. Thin shells are examples of strength through form as opposed to strength through mass; their thin ...

  16. Acoustic coupling of two parallel shells in compressible fluid

    International Nuclear Information System (INIS)

    Gerges, S.N.Y.

    1982-01-01

    Modifications are done in the acoustic impedance for a vibrating shell, due to the pressure of another similar shell. The multi-analysis method of scattering is used. The results of the impedance in function of the shell radius, the wave length, the distance between the shell axis and its vibration models are presented. (E.G.) [pt

  17. Single Shell Tank (SST) Program Plan

    International Nuclear Information System (INIS)

    HAASS, C.C.

    2000-01-01

    This document provides an initial program plan for retrieval of the single-shell tank waste. Requirements, technical approach, schedule, organization, management, and cost and funding are discussed. The program plan will be refined and updated in fiscal year 2000

  18. Single Shell Tank (SST) Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    HAASS, C.C.

    2000-03-21

    This document provides an initial program plan for retrieval of the single-shell tank waste. Requirements, technical approach, schedule, organization, management, and cost and funding are discussed. The program plan will be refined and updated in fiscal year 2000.

  19. Hydration shells exchange charge with their protein

    DEFF Research Database (Denmark)

    Abitan, Haim; Lindgård, Per-Anker; Nielsen, Bjørn Gilbert

    2010-01-01

    . In our experiments, the amplitude of an ultrasonic pressure wave is gradually increased (0–20 atm) while we simultaneously measure the Raman spectra from the hydrated protein (β-lactoglobulin and lysozyme). We detected two types of spectral changes: first, up to 70% increase in the intensity......Investigation of the interaction between a protein and its hydration shells is an experimental and theoretical challenge. Here, we used ultrasonic pressure waves in aqueous solutions of a protein to explore the conformational states of the protein and its interaction with its hydration shells...... the presence of an ultrasonic pressure, a protein and its hydration shells are in thermodynamic and charge equilibrium, i.e. a protein and its hydration shells exchange charges. The ultrasonic wave disrupts these equilibria which are regained within 30–45 min after the ultrasonic pressure is shut off....

  20. Wireless energy transfer between anisotropic metamaterials shells

    Energy Technology Data Exchange (ETDEWEB)

    Díaz-Rubio, Ana; Carbonell, Jorge; Sánchez-Dehesa, José, E-mail: jsdehesa@upv.es

    2014-06-15

    The behavior of strongly coupled Radial Photonic Crystals shells is investigated as a potential alternative to transfer electromagnetic energy wirelessly. These sub-wavelength resonant microstructures, which are based on anisotropic metamaterials, can produce efficient coupling phenomena due to their high quality factor. A configuration of selected constitutive parameters (permittivity and permeability) is analyzed in terms of its resonant characteristics. The coupling to loss ratio between two coupled resonators is calculated as a function of distance, the maximum (in excess of 300) is obtained when the shells are separated by three times their radius. Under practical conditions an 83% of maximum power transfer has been also estimated. -- Highlights: •Anisotropic metamaterial shells exhibit high quality factors and sub-wavelength size. •Exchange of electromagnetic energy between shells with high efficiency is analyzed. •Strong coupling is supported with high wireless transfer efficiency. •End-to-end energy transfer efficiencies higher than 83% can be predicted.

  1. Casimir effect in spherical shells

    International Nuclear Information System (INIS)

    Ruggiero, J.R.

    1985-01-01

    The analytic regularization method is applied to study the Casimir effect for spherical cavities. Although many works have been presented in the past few years, problems related to the elimination of the regulator parameter still remain. A way to calculate the zero point energy of a perfectly conducting spherical shell which is a miscellaneous of those presented early is here proposed, How a cancelation of divergent terms occurs and how a finite parte is obtained after the elimination of the regulator parameter is shown. As a by-product the zero point energy of the interior vibration modes is obtained and this has some relevance to the quarks bag model. This relev ance is also discussed. The calculation of the energy fom the density view is also discussed. Some works in this field are criticized. The logarithmic divergent terms in the zero point energy are studied when the interior and exterior of the sphere are considered as a medium not dispersive and characterized by a dielectric constants ε 1 and ε 2 and peermeability constants μ 1 and μ 2 respectivelly. The logarithmic divergent terms are not present in the case of ε i μ i =K, with K some constant and i=1,2. (author) [pt

  2. Membrane Shell Reflector Segment Antenna

    Science.gov (United States)

    Fang, Houfei; Im, Eastwood; Lin, John; Moore, James

    2012-01-01

    The mesh reflector is the only type of large, in-space deployable antenna that has successfully flown in space. However, state-of-the-art large deployable mesh antenna systems are RF-frequency-limited by both global shape accuracy and local surface quality. The limitations of mesh reflectors stem from two factors. First, at higher frequencies, the porosity and surface roughness of the mesh results in loss and scattering of the signal. Second, the mesh material does not have any bending stiffness and thus cannot be formed into true parabolic (or other desired) shapes. To advance the deployable reflector technology at high RF frequencies from the current state-of-the-art, significant improvements need to be made in three major aspects: a high-stability and highprecision deployable truss; a continuously curved RF reflecting surface (the function of the surface as well as its first derivative are both continuous); and the RF reflecting surface should be made of a continuous material. To meet these three requirements, the Membrane Shell Reflector Segment (MSRS) antenna was developed.

  3. Physical mechanism of surface roughening on the radial core-shell nanowire heterostructure with alloy shell

    Science.gov (United States)

    Cao, Yuanyuan; Diao, Dongfeng

    2017-05-01

    We proposed a quantitative thermodynamic theory to address the physical process of surface roughening during the epitaxial growth of core-shell NW with alloy layer. The surface roughening origins from the transformation of the Frank-van der Merwe (FM) mode to the Stranski-Krastanow (SK) mode. In addition to the radius of NW core, the composition and thickness of alloy shell could determine the growth behaviors due to their modulation to the strain. The established theoretical model not only explains the surface roughening caused by the alloy shell layer, but also provides a new way to control the growth of core-shell NW.

  4. Physical mechanism of surface roughening on the radial core-shell nanowire heterostructure with alloy shell

    Directory of Open Access Journals (Sweden)

    Yuanyuan Cao

    2017-05-01

    Full Text Available We proposed a quantitative thermodynamic theory to address the physical process of surface roughening during the epitaxial growth of core-shell NW with alloy layer. The surface roughening origins from the transformation of the Frank-van der Merwe (FM mode to the Stranski-Krastanow (SK mode. In addition to the radius of NW core, the composition and thickness of alloy shell could determine the growth behaviors due to their modulation to the strain. The established theoretical model not only explains the surface roughening caused by the alloy shell layer, but also provides a new way to control the growth of core-shell NW.

  5. Understanding the Mechanisms of Gold Shell Growth onto Polymer Microcapsules to Control Shell Thickness.

    Science.gov (United States)

    Tasker, Alison L; Hitchcock, James; Baxter, Elaine A; Cayre, Dr Olivier J; Biggs, Simon

    2017-07-04

    Polymer microcapsules have been used commercially for decades, however they have an inherent flaw which renders them impractical as a carrier of small, volatile molecules. The porous nature of the polymer shell allows for diffusion of the encapsulated molecules into the bulk. The use of metal shells is an innovative way to prevent undesired loss of small molecules from the core of microcapsules, however it is important, particularly when using expensive metals to ensure that the resulting shell is as thin as possible. Here we investigate the fundamental mechanisms controlling the gold shell thickness when a fragrance oil is encapsulated in a poly(methyl methacrylate) shell. We consider the distribution of the nanoparticles on the capsule surface, and from quantification of the adsorbed nanoparticle (NP) density and resulting shell thickness, we propose mechanisms to describe the gold shell growth for systems with high and low NP surface coverage. We suggest from our observations that the gold grows to fill in the gaps between NPs. At low NP concentrations, thicker metal shells form. We postulate that this is due to the low NP density on the surface, forcing the gold clusters to grow larger before they meet the adjacent ones. Thus, to grow the thinnest possible shells a densely packed monolayer of platinum nanoparticles is required on the capsule surface. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. An equations of motion approach for open shell systems

    International Nuclear Information System (INIS)

    Yeager, D.L.; McKoy, V.

    1975-01-01

    A straightforward scheme is developed for extending the equations of motion formalism to systems with simple open shell ground states. Equations for open shell random phase approximation (RPA) are given for the cases of one electron outside of a closed shell in a nondegenerate molecular orbital and for the triplet ground state with two electrons outside of a closed shell in degenerate molecular orbitals. Applications to other open shells and extension of the open shell EOM to higher orders are both straightforward. Results for the open shell RPA for lithium atom and oxygen molecule are given

  7. Engineered inorganic core/shell nanoparticles

    International Nuclear Information System (INIS)

    Mélinon, Patrice; Begin-Colin, Sylvie; Duvail, Jean Luc; Gauffre, Fabienne; Boime, Nathalie Herlin; Ledoux, Gilles; Plain, Jérôme; Reiss, Peter; Silly, Fabien; Warot-Fonrose, Bénédicte

    2014-01-01

    It has been for a long time recognized that nanoparticles are of great scientific interest as they are effectively a bridge between bulk materials and atomic structures. At first, size effects occurring in single elements have been studied. More recently, progress in chemical and physical synthesis routes permitted the preparation of more complex structures. Such structures take advantages of new adjustable parameters including stoichiometry, chemical ordering, shape and segregation opening new fields with tailored materials for biology, mechanics, optics magnetism, chemistry catalysis, solar cells and microelectronics. Among them, core/shell structures are a particular class of nanoparticles made with an inorganic core and one or several inorganic shell layer(s). In earlier work, the shell was merely used as a protective coating for the core. More recently, it has been shown that it is possible to tune the physical properties in a larger range than that of each material taken separately. The goal of the present review is to discuss the basic properties of the different types of core/shell nanoparticles including a large variety of heterostructures. We restrict ourselves on all inorganic (on inorganic/inorganic) core/shell structures. In the light of recent developments, the applications of inorganic core/shell particles are found in many fields including biology, chemistry, physics and engineering. In addition to a representative overview of the properties, general concepts based on solid state physics are considered for material selection and for identifying criteria linking the core/shell structure and its resulting properties. Chemical and physical routes for the synthesis and specific methods for the study of core/shell nanoparticle are briefly discussed

  8. Engineered inorganic core/shell nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Mélinon, Patrice, E-mail: patrice.melinon@univ-lyon1.fr [Institut Lumière matière Université Claude Bernard Lyon 1 et CNRS et OMNT, Domaine Scientifique de la Doua, Bâtiment Léon Brillouin, 43 Boulevard du 11 Novembre 1918, F 69622 Villeurbanne (France); Begin-Colin, Sylvie [IPCMS et OMNT, 23 rue du Loess BP 43, 67034 STRASBOURG Cedex 2 (France); Duvail, Jean Luc [IMN UMR 6502 et OMNT Campus Sciences : 2 rue de la Houssinire, BP32229, 44322 Nantes Cedex3 (France); Gauffre, Fabienne [SPM et OMNT : Institut des sciences chimiques de Rennes - UMR 6226, 263 Avenue du General Leclerc, CS 74205, 35042 RENNES Cedex (France); Boime, Nathalie Herlin [IRAMIS-NIMBE, Laboratoire Francis Perrin (CEA CNRS URA 2453) et OMNT, Bat 522, CEA Saclay, 91191 Gif sur Yvette Cedex (France); Ledoux, Gilles [Institut Lumière Matière Université Claude Bernard Lyon 1 et CNRS et OMNT, Domaine Scientifique de la Doua, Bâtiment Alfred Kastler 43 Boulevard du 11 Novembre 1918 F 69622 Villeurbanne (France); Plain, Jérôme [Universit de technologie de Troyes LNIO-ICD, CNRS et OMNT 12 rue Marie Curie - CS 42060 - 10004 Troyes cedex (France); Reiss, Peter [CEA Grenoble, INAC-SPrAM, UMR 5819 CEA-CNRS-UJF et OMNT, Grenoble cedex 9 (France); Silly, Fabien [CEA, IRAMIS, SPEC, TITANS, CNRS 2464 et OMNT, F-91191 Gif sur Yvette (France); Warot-Fonrose, Bénédicte [CEMES-CNRS, Université de Toulouse et OMNT, 29 rue Jeanne Marvig F 31055 Toulouse (France)

    2014-10-20

    It has been for a long time recognized that nanoparticles are of great scientific interest as they are effectively a bridge between bulk materials and atomic structures. At first, size effects occurring in single elements have been studied. More recently, progress in chemical and physical synthesis routes permitted the preparation of more complex structures. Such structures take advantages of new adjustable parameters including stoichiometry, chemical ordering, shape and segregation opening new fields with tailored materials for biology, mechanics, optics magnetism, chemistry catalysis, solar cells and microelectronics. Among them, core/shell structures are a particular class of nanoparticles made with an inorganic core and one or several inorganic shell layer(s). In earlier work, the shell was merely used as a protective coating for the core. More recently, it has been shown that it is possible to tune the physical properties in a larger range than that of each material taken separately. The goal of the present review is to discuss the basic properties of the different types of core/shell nanoparticles including a large variety of heterostructures. We restrict ourselves on all inorganic (on inorganic/inorganic) core/shell structures. In the light of recent developments, the applications of inorganic core/shell particles are found in many fields including biology, chemistry, physics and engineering. In addition to a representative overview of the properties, general concepts based on solid state physics are considered for material selection and for identifying criteria linking the core/shell structure and its resulting properties. Chemical and physical routes for the synthesis and specific methods for the study of core/shell nanoparticle are briefly discussed.

  9. Dynamic nonlinear analysis of shells of revolution

    International Nuclear Information System (INIS)

    Riesemann, W.A. von; Stricklin, J.A.; Haisler, W.E.

    1975-01-01

    Over the past few years a series of finite element computer programs have been developed at Texas A and M University for the static and dynamic nonlinear analysis of shells of revolution. This paper discusses one of these, DYNAPLAS, which is a program for the transient response of ring stiffened shells of revolution subjected to either asymmetric initial velocities or to asymmetric pressure loadings. Both material and geometric nonlinearities may be considered. (Auth.)

  10. Antimicrobial activity of coconut shell liquid smoke

    Science.gov (United States)

    Kailaku, SI; Syakir, M.; Mulyawanti, I.; Syah, ANA

    2017-06-01

    Coconut shell liquid smoke is produced from the pyrolysis and condensation of smoke from the burning process of coconut shell. It is known to have considerably high content of polyphenol. Beside acting as antioxidant, polyphenol is also a good antimicrobial. This research was conducted in order to study the antimicrobial activity of coconut shell liquid smoke. Coconut shell liquid smoke used in this study was produced from three different processing stages, which obtained three different grades of liquid smoke (grade 1, 2 and 3). Each sample of coconut shell liquid smoke was extracted using ethyl alcohol and petroleum ether. The extract was then analyzed for its antimicrobial activity against S. aereus, E. coli and C. albicans using well diffusion method. Total phenol and microbial microscopic structure of the liquid smoke were also examined. The results showed that there was influence of coconut shell liquid smoke on the inhibition of S. aureus, E. coli and C. albican growth. This fact was marked by the forming of clear area surrounding the well on the dish agar media. The highest percentage of inhibition showed by the extract of grade 3 coconut shell liquid smoke. This may be explained by the highest total phenol content in grade 3 liquid smoke. Microscopic examination showed that there was a breakage of microbial cell walls caused by the antimicrobial property of the liquid smoke. It was concluded that coconut shell liquid smoke was beneficial as antimicrobial agent, and while all grades of liquid smoke contains polyphenol, the content was influenced by the processing stage and thus influenced its level of microbial growth inhibition.

  11. Plate shell structures - statics and stability

    DEFF Research Database (Denmark)

    Almegaard, Henrik

    2008-01-01

    This paper describes the basic structural system, statics and spatial stability of plate shells. The structural system can be considered as a single layer of planar elements, where each element only transfers in-plane (membrane) forces to its neighbouring elements. External out-of-plane loads...... system is dual to that of a spatial truss system, which means the stringer system [1] can be applied to plate-shell structures....

  12. Determination of shell energies. Nuclear deformations and fission barriers

    International Nuclear Information System (INIS)

    Koura, Hiroyuki; Tachibana, Takahiro; Uno, Masahiro; Yamada, Masami.

    1996-01-01

    We have been studying a method of determining nuclear shell energies and incorporating them into a mass formula. The main feature of this method lies in estimating shell energies of deformed nuclei from spherical shell energies. We adopt three assumptions, from which the shell energy of a deformed nucleus is deduced to be a weighted sum of spherical shell energies of its neighboring nuclei. This shell energy should be called intrinsic shell energy since the average deformation energy also acts as an effective shell energy. The ground-state shell energy of a deformed nucleus and its equilibrium shape can be obtained by minimizing the sum of these two energies with respect to variation of deformation parameters. In addition, we investigate the existence of fission isomers for heavy nuclei with use of the obtained shell energies. (author)

  13. The off-shell c-map

    International Nuclear Information System (INIS)

    Banerjee, Nabamita; Wit, Bernard de; Katmadas, Stefanos

    2016-01-01

    The off-shell version of the c-map is presented, based on a systematic off-shell reduction from four to three space-time dimensions for supergravity theories with eight supercharges. In the reduction, the R-symmetry group is enhanced to local [SU(2)×SU(2)]/ℤ 2 ≅SO(4) and the c-map is effected by a parity transformation in the internal space that interchanges the two SU(2) factors. Vector and tensor supermultiplets are each others conjugate under the c-map and both can be dualized in three dimensions to (on-shell) hypermultiplets. As shown in this paper the off-shell formulation indeed leads to a clarification of many of the intricate issues that play a role in the c-map. The results for off-shell Lagrangians quadratic in space-time derivatives are analyzed in detail and compared to the literature. The underlying reasons are identified why not all of the four-dimensional tensor multiplet Lagrangians can be in the image of the c-map. The advantage of the off-shell approach is, that it also enables a systematic analysis of theories with higher-derivative couplings. This is demonstrated for a particular subclass of such theories, which, under certain conditions, are consistent under the c-map. In principle, explicit results for realistic four-dimensional type-II string compactifications can be explored in this way.

  14. Lessons Not Learned. The Other Shell Report 2004

    International Nuclear Information System (INIS)

    Harden, M.; Walker, N.; Griffiths, H.; Verweij, M.

    2005-06-01

    The third alternative Shell Corporate Social Responsibility (CSR) report is presented on behalf of several of the many communities that live on Shell's 'fencelines', next to Shell's refineries, depots and pipelines. This 2004 report builds on reports of the past two years 'Failing the Challenge', (2002) and 'Behind the Shine' (2003) which chronicled Shell's impacts around the world. It gives critical updates of Shell's performance over the past year

  15. Variation in Orthologous Shell-Forming Proteins Contribute to Molluscan Shell Diversity.

    Science.gov (United States)

    Jackson, Daniel J; Reim, Laurin; Randow, Clemens; Cerveau, Nicolas; Degnan, Bernard M; Fleck, Claudia

    2017-11-01

    Despite the evolutionary success and ancient heritage of the molluscan shell, little is known about the molecular details of its formation, evolutionary origins, or the interactions between the material properties of the shell and its organic constituents. In contrast to this dearth of information, a growing collection of molluscan shell-forming proteomes and transcriptomes suggest they are comprised of both deeply conserved, and lineage specific elements. Analyses of these sequence data sets have suggested that mechanisms such as exon shuffling, gene co-option, and gene family expansion facilitated the rapid evolution of shell-forming proteomes and supported the diversification of this phylum specific structure. In order to further investigate and test these ideas we have examined the molecular features and spatial expression patterns of two shell-forming genes (Lustrin and ML1A2) and coupled these observations with materials properties measurements of shells from a group of closely related gastropods (abalone). We find that the prominent "GS" domain of Lustrin, a domain believed to confer elastomeric properties to the shell, varies significantly in length between the species we investigated. Furthermore, the spatial expression patterns of Lustrin and ML1A2 also vary significantly between species, suggesting that both protein architecture, and the regulation of spatial gene expression patterns, are important drivers of molluscan shell evolution. Variation in these molecular features might relate to certain materials properties of the shells of these species. These insights reveal an important and underappreciated source of variation within shell-forming proteomes that must contribute to the diversity of molluscan shell phenotypes. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  16. Deux comparatismes pour une anthropologie historique

    Directory of Open Access Journals (Sweden)

    Pierre-Olivier Dittmar

    2010-06-01

    Full Text Available Malgré des appels répétés depuis plus d’un siècle de la part des historiens, le comparatisme, qui est un élément majeur de l’anthropologie, demeure très peu pratiqué. Ce rejet est ici analysé comme un refus d’une quête des invariants de l’homme qui aboutirait à des résultats an-historiques. Un autre comparatisme est cependant possible, qui instrumentalise la confrontation des univers pour mieux relever les différences. C’est les conditions et les avantages d’une telle pratique qui sont ici exposés, à partir de l’exemple des tabous alimentaires.Despite the repeated calls by some historians for more than a century, many seldom practice a major element of anthropology: comparativism. This paper will analyze this rejection as a refusal to investigate the constants of the human experience that lead to a-historical conclusions. However, another kind of comparativism is possible, one that examines the contrast between cultures in order to better understand their differences. Using the case of dietary taboos, this paper will look at the conditions and advantages of such a practice.Nonostante i molteplici appelli da più di un secolo da parte degli storici, il comparatismo, che costituisce un elemento fondamentale dell’antropologia, è ancora oggi troppo poco spesso praticato. Si proporrà di interpretare questo rifiuto come un rifiuto della ricerca di invarianti umane che condurrebbe a risultati a-storici. Un’altra forma di comparatismo è nondimeno possibile, una forma precisamente che ricorre al confronto di universi diversi per meglio comprenderne le difference reciproche. L’articolo espone le condizioni e i vantaggi di questa metodologia di ricerca, a partire dall’esempio degli interdetti alimentari.

  17. Kenya : tous les projets | Page 3 | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le réseau GEOHealth d'Afrique orientale pour la prévention des risques pour la santé des travailleurs et la salubrité environnementale. Projet. La charge de morbidité résultant des dangers pour la santé ... Una Hakika : Porter à grande échelle les solutions numériques pour la gestion des conflits au Kenya et en Birmanie.

  18. Accroître les occasions d'affaire pour les jeunes Africains dans les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le projet permettra d'élaborer et de mettre en oeuvre des méthodes pour répertorier les marchés de produits agricoles précis et pour trouver des possibilités d'activités agroalimentaires viables pour les jeunes. L'équipe de projet recrutera des jeunes possédant des aptitudes pour l'entrepreneuriat et leur enseignera les ...

  19. Local shell-to-shell energy transfer via nonlocal interactions in fluid ...

    Indian Academy of Sciences (India)

    The computation has been done using first-order perturbative field theory. In three dimensions, magnitude of triad interactions is large for nonlocal triads, and small for local triads. However, the shell-to-shell energy transfer rate is found to be local and forward. This result is due to the fact that the nonlocal triads occupy much ...

  20. Core-shell microspheres with porous nanostructured shells for liquid chromatography.

    Science.gov (United States)

    Ahmed, Adham; Skinley, Kevin; Herodotou, Stephanie; Zhang, Haifei

    2018-01-01

    The development of new stationary phases has been the key aspect for fast and efficient high-performance liquid chromatography separation with relatively low backpressure. Core-shell particles, with a solid core and porous shell, have been extensively investigated and commercially manufactured in the last decade. The excellent performance of core-shell particles columns has been recorded for a wide range of analytes, covering small and large molecules, neutral and ionic (acidic and basic), biomolecules and metabolites. In this review, we first introduce the advance and advantages of core-shell particles (or more widely known as superficially porous particles) against non-porous particles and fully porous particles. This is followed by the detailed description of various methods used to fabricate core-shell particles. We then discuss the applications of common silica core-shell particles (mostly commercially manufactured), spheres-on-sphere particles and core-shell particles with a non-silica shell. This review concludes with a summary and perspective on the development of stationary phase materials for high-performance liquid chromatography applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Sexual selection on land snail shell ornamentation: a hypothesis that may explain shell diversity

    NARCIS (Netherlands)

    Schilthuizen, M.

    2003-01-01

    Background: Many groups of land snails show great interspecific diversity in shell ornamentation, which may include spines on the shell and flanges on the aperture. Such structures have been explained as camouflage or defence, but the possibility that they might be under sexual selection has not

  2. Local shell-to-shell energy transfer via nonlocal interactions in fluid ...

    Indian Academy of Sciences (India)

    August 2005 physics pp. 297–310. Local shell-to-shell energy transfer via nonlocal interactions in fluid turbulence. MAHENDRA K VERMA1, ARVIND AYYER2, OLIVIER ... MS received 1 October 2004; revised 2 March 2005; accepted 13 April 2005 ...... Kraichnan [23,24] first raised the above objection, and proposed.

  3. Preparation of polymeric pour point depressants for shale oil

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Tingyn; Wang, Jilin [Liaoning Univ. of Petroleum and Chemical Technology, Fushun (China). Dept. of Petrochemical Technology; Jin, Jingsen [Petrochina Fushun Petrochemical Company Refinery No. 2 (China)

    2006-06-15

    The melt esterification of acrylic acid and higher alcohols without solvent is carried out and the effects of factors on the production efficiency of acrylic higher alcohol ester are investigated. Optimum reaction conditions are obtained at molar ratio of acrylic acid to higher alcohol 1.2:1.0 and reflux time 7 h at 110-140{sup o}C in stepwise heating. At this point the acrylic higher alcohol ester will be polymerized with maleic anhydride, phenylethylene, and vinyl acetate, and formed into four components. Copolymer shale oil pour point depressant and the polymerization condition are also studied by orthogonal method. The effect of pour point depressants is best when the monomer molar ratio is 8:1:1:1 at 80{sup o}C for 8 h for reflux and the benzoyl peroxide is added. The pour point of Fushun shale oil reduces by 9{sup o}C when only 0.5% copolymer is added. (Author)

  4. identification de caractéristiques agronomiques pour le diagnostic

    African Journals Online (AJOL)

    ACSS

    La régénération des vieux vergers de cacaoyers (Theobrama cacao L.) est une des stratégies mises en place en. Côte d'Ivoire pour assurer une production durable de cacao. Une étude a été conduite en vue d'élaborer un guide pour réaliser un diagnostic rapide et adéquat des vergers et prendre la bonne décision de ...

  5. Etude et simulation des techniques de multiplexage OFDM pour une ...

    African Journals Online (AJOL)

    La simulation de ce modèle a révélé que, pour un même RSB de 20 dB, la technique ACO-OFDM (présentant un TEB de 0.0083) est moins sensible au bruit que la technique DCO-OFDM (dont le TEB est de 0.3413). Il est aussi remarqué que, pour un même RSB, l'implémentation de la DFT en matière de génération de ...

  6. Ethiopia : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le réseau GEOHealth d'Afrique orientale pour la prévention des risques pour la santé des travailleurs et la salubrité environnementale. Projet. La charge de morbidité ... Projet. L'Éthiopie réalise des progrès en ce qui concerne la gestion de l'économie de marché. Date de début : 16 octobre 2013. End Date: 14 août 2015.

  7. Une charte éthique pour le Big Data

    OpenAIRE

    De Filippi, Primavera

    2013-01-01

    Des implications métiers, sans nul doute, pour ces obligations particulières qui doivent être respectées lors de l'utilisation de données provenant du Big Data, afin de garantir leur qualité, leur conservation et les conditions de leur réutilisation tant d'un point de vue technique, économique que légal. Une charte, outil pour nous y aider, vient d' être proposée.

  8. Emploi et croissance | Page 18 | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Malgré les avancées importantes réalisées dans le domaine du développement au cours des dernières décennies, les pays en développement font toujours face à de grands défis dans leurs efforts pour lutter contre la pauvreté. Les programmes de transferts en espèces se révèlent des outils efficaces pour réduire la ...

  9. Lithography-free shell-substrate isolation for core-shell GaAs nanowires.

    Science.gov (United States)

    Haggren, Tuomas; Perros, Alexander Pyymaki; Jiang, Hua; Huhtio, Teppo; Kakko, Joona-Pekko; Dhaka, Veer; Kauppinen, Esko; Lipsanen, Harri

    2016-07-08

    A facile and scalable lithography-free technique(5) for the rapid construction of GaAs core-shell nanowires incorporating shell isolation from the substrate is reported. The process is based on interrupting NW growth and applying a thin spin-on-glass (SOG) layer to the base of the NWs and resuming core-shell NW growth. NW growth occurred in an atmospheric pressure metalorganic vapour phase epitaxy (MOVPE) system with gold nanoparticles used as catalysts for the vapour-liquid-solid growth. It is shown that NW axial core growth and radial shell growth can be resumed after interruption and even exposure to air. The SOG residues and native oxide layer that forms on the NW surface are shown to prevent or perturb resumption of epitaxial NW growth if not removed. Both HF etching and in situ annealing of the air-exposed NWs in the MOVPE were shown to remove the SOG residues and native oxide layer. While both procedures are shown capable of removing the native oxide and enabling resumption of epitaxial NW growth, in situ annealing produced the best results and allowed construction of pristine core-shell NWs. No growth occurred on SOG and it was observed that axial NW growth was more rapid when a SOG layer covered the substrate. The fabricated p-core/n-shell NWs exhibited diode behaviour upon electrical testing. The isolation of the NW shells from the substrate was confirmed by scanning electron microscopy and electrical measurements. The crystal quality of the regrown core-shell NWs was verified with a high resolution transmission electron microscope. The reported technique potentially provides a pathway using MOVPE for scalable and high-throughput production of shell-substrate isolated core-shell NWs on an industrial scale.

  10. Guide pour la conception des dispositifs de franchissement des barrages pour les poissons migrateurs

    Directory of Open Access Journals (Sweden)

    LARINIER M.

    1983-10-01

    Full Text Available L'auteur rappelle dans cette note les principes de base devant guider le projeteur lors de la conception des ouvrages de franchissement de barrages ou d'obstacles pour les poissons migrateurs. L'accent est mis sur l'importance de la situation et de l'attractivité de ces ouvrages. Les principes de fonctionnement et les critères de dimensionnement des différents types de passes (passes à bassins successifs, passes à ralentisseurs, écluses et ascenseurs sont évoqués. Dans la dernière partie sont recensés les éléments à prendre en compte lors de l'établissement d'un projet de passe.

  11. CIRCUMSTELLAR SHELL FORMATION IN SYMBIOTIC RECURRENT NOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Kevin; Bildsten, Lars [Department of Physics, Broida Hall, University of California, Santa Barbara, CA 93106 (United States)

    2012-12-20

    We present models of spherically symmetric recurrent nova shells interacting with circumstellar material (CSM) in a symbiotic system composed of a red giant (RG) expelling a wind and a white dwarf accreting from this material. Recurrent nova eruptions periodically eject material at high velocities ({approx}> 10{sup 3} km s{sup -1}) into the RG wind profile, creating a decelerating shock wave as CSM is swept up. High CSM densities cause the shocked wind and ejecta to have very short cooling times of days to weeks. Thus, the late-time evolution of the shell is determined by momentum conservation instead of energy conservation. We compute and show evolutionary tracks of shell deceleration, as well as post-shock structure. After sweeping up all the RG wind, the shell coasts at a velocity {approx}100 km s{sup -1}, depending on system parameters. These velocities are similar to those measured in blueshifted CSM from the symbiotic nova RS Oph, as well as a few Type Ia supernovae that show evidence of CSM, such as 2006X, 2007le, and PTF 11kx. Supernovae occurring in such systems may not show CSM interaction until the inner nova shell gets hit by the supernova ejecta, days to months after the explosion.

  12. SHELL DISEASES AND TOXINS REGULATED BY LAW

    Directory of Open Access Journals (Sweden)

    Natalija Topić Popović

    1999-06-01

    Full Text Available There is a long tradition of cultivating shells in Croatia, and the shell industry has a good perspective of further development. Since shells are delicate organisms that require special breeding conditions and climate, they are also subject to many diseases. Bonamiosis, haplospioridiosis, marteiliosis, microcytosis and perkinsosis are stated by the International Bureau for Epizootics as shell diseases that, in keeping with law, must be reported, and iridovirosis as a disease of a potential international importance. The same diseases are regulated by the Veterinary Law from 1997 as infectious diseases prevention of which is of an interest for the Republic of Croatia. Although, according to the law, it does not have to be prevented, in this article the disease Mytilicola is also described. According to the Health Department Statute from 1994, eatable part of shells are being tested for toxins of some marine dinoflagelates that can damage human health, and these are PSP (Paralytic Shellfish Poison, DSP (Diarrhoeic Shellfish Poison and NSP (Neuroparalytic Shellfish Poison.

  13. Double shell planar experiments on OMEGA

    Science.gov (United States)

    Dodd, E. S.; Merritt, E. C.; Palaniyappan, S.; Montgomery, D. S.; Daughton, W. S.; Schmidt, D. W.; Cardenas, T.; Wilson, D. C.; Loomis, E. N.; Batha, S. H.; Ping, Y.; Smalyuk, V. A.; Amendt, P. A.

    2017-10-01

    The double shell project is aimed at fielding neutron-producing capsules at the National Ignition Facility (NIF), in which an outer low-Z ablator collides with an inner high-Z shell to compress the fuel. However, understanding these targets experimentally can be challenging when compared with conventional single shell targets. Halfraum-driven planar targets at OMEGA are being used to study physics issues important to double shell implosions outside of a convergent geometry. Both VISAR and radiography through a tube have advantages over imaging through the hohlraum and double-shell capsule at NIF. A number physics issues are being studied with this platform that include 1-d and higher dimensional effects such as defect-driven hydrodynamic instabilities from engineering features. Additionally, the use of novel materials with controlled density gradients require study in easily diagnosed 1-d systems. This work ultimately feeds back into the NIF capsule platform through manufacturing tolerances set using data from OMEGA. Supported under the US DOE by the LANS, LLC under contract DE-AC52-06NA25396. LA-UR-17-25386.

  14. Risques sur Internet pour les enfants et les jeunes: données récentes pour la Suisse

    OpenAIRE

    Hermida Martin; Signer Sara

    2013-01-01

    La plupart du temps on entend parler des risques d’Internet pour les enfants et les jeunes à la suite d’événements spectaculaires. L’étude «EU Kids Online: Suisse» s’est penchée sur l’expérience des risques sur Internet de jeunes âgés de neuf à seize ans pour fournir une base de données solide qui devrait alimenter et consolider les débats sur le sujet tant dans le grand public que parmi les acteurs politiques. Comme le montrent les résultats la probabilité pour les jeunes de ...

  15. Vibrational analysis of submerged cylindrical shells based on elastic foundations

    International Nuclear Information System (INIS)

    Shah, A.G.; Naeem, M.N.

    2014-01-01

    In this study a vibration analysis was performed of an isotropic cylindrical shell submerged in fluid, resting on Winkler and Pasternak elastic foundations for simply supported boundary condition. Love's thin shell theory was exploited for strain- and curvature- displacement relationship. Shell problem was solved by using wave propagation approach. Influence of fluid and Winkler as well as Pasternak elastic foundations were studied on the natural frequencies of submerged isotropic cylindrical shells. Results were validated by comparing with the existing results in literature. Vibration, Submerged cylindrical shell, Love's thin shell theory, Wave propagation method, Winkler and Pasternak foundations. (author)

  16. Strontium clusters: electronic and geometry shell effects

    DEFF Research Database (Denmark)

    Lyalin, Andrey G.; Solov'yov, Ilia; Solov'yov, Andrey V.

    2008-01-01

    charged strontium clusters consisting of up to 14 atoms, average bonding distances, electronic shell closures, binding energies per atom, and spectra of the density of electronic states (DOS). It is demonstrated that the size-evolution of structural and electronic properties of strontium clusters...... is governed by an interplay of the electronic and geometry shell closures. Influence of the electronic shell effects on structural rearrangements can lead to violation of the icosahedral growth motif of strontium clusters. It is shown that the excessive charge essentially affects the optimized geometry...... of strontium clusters. Ionization of small strontium clusters results in the alteration of the magic numbers. The strong dependence of the DOS spectra on details of ionic structure allows one to perform a reliable geometry identification of strontium clusters....

  17. Modeling of microencapsulated polymer shell solidification

    International Nuclear Information System (INIS)

    Boone, T.; Cheung, L.; Nelson, D.; Soane, D.; Wilemski, G.; Cook, R.

    1995-01-01

    A finite element transport model has been developed and implemented to complement experimental efforts to improve the quality of ICF target shells produced via controlled-mass microencapsulation. The model provides an efficient means to explore the effect of processing variables on the dynamics of shell dimensions, concentricity, and phase behavior. Comparisons with experiments showed that the model successfully predicts the evolution of wall thinning and core/wall density differences. The model was used to efficiently explore and identify initial wall compositions and processing temperatures which resulted in concentricity improvements from 65 to 99%. The evolution of trace amounts of water entering into the shell wall was also tracked in the simulations. Comparisons with phase envelope estimations from modified UNIFAP calculations suggest that the water content trajectory approaches the two-phase region where vacuole formation via microphase separation may occur

  18. Spectrophotometry of the shell around AG Carinae

    Science.gov (United States)

    Mitra, P. Mila; Dufour, Reginald J.

    1990-01-01

    Spatially-resolved long-slit spectrophotometry are presented for two regions of the shell nebula around the P-Cygni variable star AG Carinae. The spectra cover the 3700-6800 A wavelength range. Emission-line diagnostics are used to derive extinction, electron temperatures, and densities for various positions in the nebula. The chemical abundances and ionization structure are calculated and compared with other types of planetary nebulae and shells around other luminous stars. It is found that the N/O and N/S ratios of Ag Car are high compared to solar neighborhood ISM values. The O/H depletion found for the AG Car shell approaches that found in the condensations of the Eta Car system.

  19. Double shell tanks emergency pumping plan

    Energy Technology Data Exchange (ETDEWEB)

    Tangen, M.J.

    1994-09-26

    At the request of the Department of Energy (DOE), a formal plan for the emergency transfer of waste from a leaking double shell tank to a designated receiver tank has been developed. This plan is in response to the priority 2 safety issue ``Response to a leaking double-shell tank`` in the DOE Report to Congress, 1991. The plan includes the tanks in four of the east tank farms and one of the west farms. The background information and supporting calculations used for the creation of the emergency plan are discussed in this document. The scope of this document is all of the double shell tanks in the AN, AP, AW, AY, and SY farms. The transfer lines, flush pits, and valve pits involved in the transfer of waste between these farms are also included in the scope. Due to the storage of high heat waste, AZ farm is excluded at this time.

  20. Complete Surface Mapping of ICF Shells

    International Nuclear Information System (INIS)

    Stephens, R.B.; Olson, D.; Huang, H.; Gibson, J.B.

    2004-01-01

    Inertial confinement fusion shells have previously been evaluated on the basis of microscopic examination for local defects and limited surface profiling to represent their average fluctuation power. Since defects are local, and don't always have visible edges, this approach both misses some important fluctuations and doesn't properly represent the spatially dependent surface fluctuation power. We have taken the first step toward correcting this problem by demonstrating the capability to completely map the surface of a NIF shell with the resolution to account for all modes. This allows complete accounting of all the surface fluctuations. In the future this capability could be used for valuable shells to generate a complete r(θ, φ) surface map for accurate 3-D modeling of a shot

  1. COMPLETE SURFACE MAPPING OF ICF SHELLS

    International Nuclear Information System (INIS)

    STEPHENS, R.B.; OLSON, D.; HUANG, H.; GIBSON, J.B.

    2003-09-01

    OAK-B135 Inertial confinement fusion shells have previously been evaluated on the basis of microscopic examination for local defects and limited surface profiling to represent their average fluctuation power. Since defects are local, and don't always have visible edges, this approach both misses some important fluctuations and doesn't properly represent the spatially dependent surface fluctuation power. they have taken the first step toward correcting this problem by demonstrating the capability to completely map the surface of a NIF shell with the resolution to account for all modes. This allows complete accounting of all the surface fluctuations. In the future this capability could be used for valuable shells to generate a complete r(θ,ψ) surface map for accurate 3-D modeling of a shot

  2. Anticavitation and Differential Growth in Elastic Shells

    KAUST Repository

    Moulton, Derek E.

    2010-07-22

    Elastic anticavitation is the phenomenon of a void in an elastic solid collapsing on itself. Under the action of mechanical loading alone typical materials do not admit anticavitation. We study the possibility of anticavitation as a consequence of an imposed differential growth. Working in the geometry of a spherical shell, we seek radial growth functions which cause the shell to deform to a solid sphere. It is shown, surprisingly, that most material models do not admit full anticavitation, even when infinite growth or resorption is imposed at the inner surface of the shell. However, void collapse can occur in a limiting sense when radial and circumferential growth are properly balanced. Growth functions which diverge or vanish at a point arise naturally in a cumulative growth process. © 2010 Springer Science+Business Media B.V.

  3. A refined element-based Lagrangian shell element for geometrically nonlinear analysis of shell structures

    Directory of Open Access Journals (Sweden)

    Woo-Young Jung

    2015-04-01

    Full Text Available For the solution of geometrically nonlinear analysis of plates and shells, the formulation of a nonlinear nine-node refined first-order shear deformable element-based Lagrangian shell element is presented. Natural co-ordinate-based higher order transverse shear strains are used in present shell element. Using the assumed natural strain method with proper interpolation functions, the present shell element generates neither membrane nor shear locking behavior even when full integration is used in the formulation. Furthermore, a refined first-order shear deformation theory for thin and thick shells, which results in parabolic through-thickness distribution of the transverse shear strains from the formulation based on the third-order shear deformation theory, is proposed. This formulation eliminates the need for shear correction factors in the first-order theory. To avoid difficulties resulting from large increments of the rotations, a scheme of attached reference system is used for the expression of rotations of shell normal. Numerical examples demonstrate that the present element behaves reasonably satisfactorily either for the linear or for geometrically nonlinear analysis of thin and thick plates and shells with large displacement but small strain. Especially, the nonlinear results of slit annular plates with various loads provided the benchmark to test the accuracy of related numerical solutions.

  4. Degree of Acetylization Chitosan Gonggong Snail Shells

    Science.gov (United States)

    Horiza, H.; Iskandar, I.; Aldo, N.

    2018-04-01

    Chitosan is a polysaccharide obtained from the deacetylation of chitin, which is generally derived from crustacean animal waste and animal skins other sea. One marine animals that have compounds that can be processed chitin chitosan is derived from the snail Gonggong marine waters of Riau Islands province. The purpose of this study was to determine the degree of chitosan from the shells of snails asetilisasi Gonggong. This research is an experimental research laboratory. The results of this study indicate that the degree of chitosan shell snail deasetilisasi Gonggong is 70.27%.

  5. Projected shell model description for nuclear isomers

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Y. [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240, Popular Republic (China)

    2008-12-15

    The study of nuclear isomer properties is a current research focus. To describe isomers, we present a method based on the Projected Shell Model. Two kinds of isomers, {kappa}-isomers and shape isomers, are discussed. For the {kappa}-isomer treatment, {kappa}-mixing is properly implemented in the model. It is found however that in order to describe the strong {kappa}-violation more efficiently, it may be necessary to further introduce triaxiality into the shell model basis. To treat shape isomers, a scheme is outlined which allows mixing those configurations belonging to different shapes. (Author)

  6. Nitride stabilized core/shell nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Kuttiyiel, Kurian Abraham; Sasaki, Kotaro; Adzic, Radoslav R.

    2018-01-30

    Nitride stabilized metal nanoparticles and methods for their manufacture are disclosed. In one embodiment the metal nanoparticles have a continuous and nonporous noble metal shell with a nitride-stabilized non-noble metal core. The nitride-stabilized core provides a stabilizing effect under high oxidizing conditions suppressing the noble metal dissolution during potential cycling. The nitride stabilized nanoparticles may be fabricated by a process in which a core is coated with a shell layer that encapsulates the entire core. Introduction of nitrogen into the core by annealing produces metal nitride(s) that are less susceptible to dissolution during potential cycling under high oxidizing conditions.

  7. Linux Command Line and Shell Scripting Bible

    CERN Document Server

    Blum, Richard

    2011-01-01

    The authoritative guide to Linux command line and shell scripting?completely updated and revised [it's not a guide to Linux as a whole ? just to scripting] The Linux command line allows you to type specific Linux commands directly to the system so that you can easily manipulate files and query system resources, thereby permitting you to automate commonly used functions and even schedule those programs to run automatically. This new edition is packed with new and revised content, reflecting the many changes to new Linux versions, including coverage of alternative shells to the default bash shel

  8. Translational invariant shell model for Λ hypernuclei

    Directory of Open Access Journals (Sweden)

    Jolos R.V.

    2016-01-01

    Full Text Available We extend shell model for Λ hypernuclei suggested by Gal and Millener by including 2ћω excitations in the translation invariant version to estimate yields of different hyperfragments from primary p-shell hypernuclei. We are inspired by the first successful experiment done at MAMI which opens way to study baryon decay of hypernuclei. We use quantum numbers of group SU(4, [f], and SU(3, (λμ, to classify basis wave functions and calculate coefficients of fractional parentage.

  9. Shell model calculations for exotic nuclei

    International Nuclear Information System (INIS)

    Brown, B.A.; Wildenthal, B.H.

    1991-01-01

    A review of the shell-model approach to understanding the properties of light exotic nuclei is given. Binding energies including p and p-sd model spaces and sd and sd-pf model spaces; cross-shell excitations around 32 Mg, including weak-coupling aspects and mechanisms for lowering the ntw excitations; beta decay properties of neutron-rich sd model, of p-sd and sd-pf model spaces, of proton-rich sd model space; coulomb break-up cross sections are discussed. (G.P.) 76 refs.; 12 figs

  10. Forced vibrations of rotating circular cylindrical shells

    International Nuclear Information System (INIS)

    Igawa, Hirotaka; Maruyama, Yoshiyuki; Endo, Mitsuru

    1995-01-01

    Forced vibrations of rotating circular cylindrical shells are investigated. Basic equations, including the effect of initial stress due to rotation, are formulated by the finite-element method. The characteristic relations for finite elements are derived from the energy principle by considering the finite strain. The equations of motion can be separated into quasi-static and dynamic ones, i.e., the equations in the steady rotating state and those in the vibration state. Radial concentrated impulses are considered as the external dynamic force. The transient responses of circular cylindrical shells are numerically calculated under various boundary conditions and rotating speeds. (author)

  11. Interface Fracture in Adhesively Bonded Shell Structures

    DEFF Research Database (Denmark)

    Jensen, Henrik Myhre

    2007-01-01

    Two methods for the prediction of crack propagation through the interface of adhesively bonded shells are discussed. One is based on a fracture mechanics approach; the other is based on a cohesive zone approach. Attention is focussed on predicting the shape of the crack front and the critical...... to take into account effects such as plastic deformation in the adhering shells, and to take into account effects of large local curvatures of the interface crack front. The comparison shows a convergence of the results based on the cohesive zone model towards the results based on a fracture mechanics...

  12. Shell Colour Polymorphism in Bulla ampulla

    DEFF Research Database (Denmark)

    Cedhagen, Tomas

    1999-01-01

    Colour patterns of Bulla ampulla shells collected from Africa eastward to Pacific Islands were studied. 1\\vo common colour morphs were found. The typical morph is commonest. It is closely and finely mottled or all over with pinkish-gray on a creamy or flesh~tinted ground, with darker clouds......, irregular, V-shaped, or as longitudinal bands. The colouration of the other common morph is more uniform. It is lacking the darker clouds or bands and the colour is more greyish. The entire shell surface is densely mottled all over with small brown spots on a grey or beige background. Both morphs seem...

  13. Galileon radiation from a spherical collapsing shell

    Energy Technology Data Exchange (ETDEWEB)

    Martín-García, Javier [Instituto de Física Teórica UAM/CSIC,C/ Nicolás Cabrera 15, E-28049 Madrid (Spain); Vázquez-Mozo, Miguel Á. [Instituto Universitario de Física Fundamental y Matemáticas (IUFFyM),Universidad de Salamanca, Plaza de la Merced s/n, E-37008 Salamanca (Spain)

    2017-01-17

    Galileon radiation in the collapse of a thin spherical shell of matter is analyzed. In the framework of a cubic Galileon theory, we compute the field profile produced at large distances by a short collapse, finding that the radiated field has two peaks traveling ahead of light fronts. The total energy radiated during the collapse follows a power law scaling with the shell’s physical width and results from two competing effects: a Vainshtein suppression of the emission and an enhancement due to the thinness of the shell.

  14. Theoretical spectroscopy and the fp shell

    International Nuclear Information System (INIS)

    Poves, A.; Zuker, A.

    1980-01-01

    The recently developed quasiconfiguration method is applied to fp shell nuclei. Second order degenerate perturbation theory is shown to be sufficient to produce, for low lying states, the same results as large diagonalizations in the f(7/2)p(3/2)p(1/2)f(5/2)sup(n) full space. due to the operation of linked cluster mechanisms. Realistic interactions with minimal monopole changes are shown to be successful in reproducing spectra, binding energies, quadrupole moments and transition rates. Large shell model spaces are seen to exhibit typical many body behaviour. Quasiconfigurations allow insight into the underlying coupling schemes

  15. Simulation of the stress computation in shells

    Science.gov (United States)

    Salama, M.; Utku, S.

    1978-01-01

    A self-teaching computer program is described, whereby the stresses in thin shells can be computed with good accuracy using the best fit approach. The program is designed for use in interactive game mode to allow the structural engineer to learn about (1) the major sources of difficulties and associated errors in the computation of stresses in thin shells, (2) possible ways to reduce the errors, and (3) trade-off between computational cost and accuracy. Included are derivation of the computational approach, program description, and several examples illustrating the program usage.

  16. Linux command line and shell scripting bible

    CERN Document Server

    Blum, Richard

    2014-01-01

    Talk directly to your system for a faster workflow with automation capability Linux Command Line and Shell Scripting Bible is your essential Linux guide. With detailed instruction and abundant examples, this book teaches you how to bypass the graphical interface and communicate directly with your computer, saving time and expanding capability. This third edition incorporates thirty pages of new functional examples that are fully updated to align with the latest Linux features. Beginning with command line fundamentals, the book moves into shell scripting and shows you the practical application

  17. Publications | Page 46 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La modélisation mathématique éclaire les politiques de prévention du VIH en Chine. Un projet de recherche financé par le CRDI utilise la modélisation mathématique pour influer sur les politiques locales et nationales de réduction de la transmission du VIH en Chine.

  18. Tanzanie | Page 22 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Read more about Lutte intégrée contre les maladies humaines et animales pour les bergers contraints à la sédentarisation en Tanzanie. Langue French. Read more about Integrated Human and Animal Disease Control for Tanzanian Pastoralists Facing Settlement. Langue English. Read more about Stratégie sanitaire ...

  19. Kenya | Page 31 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Accueil · Sud du Sahara. Kenya. Kenya. Read more about Visiting Fellowship on Governance and Corruption. Langue English. Read more about Lutte intégrée contre les maladies humaines et animales pour les bergers contraints à la sédentarisation en Tanzanie. Langue French. Read more about Integrated Human and ...

  20. Projet pilote pour le programme national de recherche et de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'idée d'un programme national de recherche et de formation (PRIDE en espagnol) est issue du projet Mise en place de systèmes d'apprentissage au Honduras (projet 100133), soutenu par le CRDI. La subvention est accordée pour appuyer une version pilote de PRIDE, reposant sur deux appels à propositions.

  1. Publications | Page 55 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    élaboration de sa prochaine stratégie quinquennale, le CRDI a organisé. ... Au cours de la dernière décennie, un certain nombre d'initiatives au Canada ont permis de mettre au point des stratégies et des forums pour permettre la mise en commun ...

  2. Inde | Page 60 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    A study on mobile phone use by the poor has resulted in the cancellation of a plan to tax mobile usage in Bangladesh. Surveys on mobile expenditures in several ... for many low-income households in India. To kill the germs, people pour water into clear plastic bottles and then leave them out in the sun for several hours.

  3. Livres | Page 31 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Asie et du Sud-Est,auraient pu, en principe, partir de la Chine pour se rendre à Singapouren se balançant d'arbre. Maison(s) d'édition : CRDI. ISBN: Épuisé. Couverture du livre Community Assessment of Natural Food Sources of Vitamin A ...

  4. Assessment of the efficacy of Deltamethrin 1% pours- on (Smash ...

    African Journals Online (AJOL)

    Ethiop. Vet. J., 2014, 18 (1), 17-27. Assessment of the efficacy of Deltamethrin 1% pours- on (Smash) and Deltamethrin 1% SC (Pali) and com- parison of their mode of applications against ticks in. Ethiopia. Sileshi Mekonnen. Current address: Sileshi.Mekonnen@fao.org; FAO Ethiopia, P.O.Box 5536, Addis Ababa, Ethiopia.

  5. Recherche | Page 5 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    , vous apprendrez les techniques fondamentales de rédaction efficace, à rédiger pour des publications . ... Le tabagisme se répand rapidement en Afrique subsaharienne sous l'impulsion d'une forte croissance économique et des tactiques .

  6. Tanzanie | Page 44 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Read more about Decades of cassava research bear fruit. Langue English. Adressez-vous à un économiste en Afrique, et il est fort probable qu'il ait profité du programme de formation du Consortium pour la recherche économique en Afrique ( AERC ). Read more about Des économistes africains favorisent la croissance et ...

  7. Vaincre le vampire violet | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Est depuis le début des années 1990 lorsque le Centre de recherches pour le développement international, une société d'État canadienne, l'a invité à se pencher sur le problème de la striga en Afrique subsaharienne.

  8. Investir dans les conseils scientifiques pour les gouvernements afin ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    10 oct. 2017 ... S'attaquer à la marginalisation, à la criminalité et à la violence chez les jeunes - le rôle du capital social communautaire. Il est maintenant reconnu que les adolescents ont besoin d'un capital social positif (réseaux sociaux, relations interpersonnelles) pour devenir des adultes productifs et socialement.

  9. Publications | Page 163 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    An Introduction to the Human Development and Capability Approach : Freedom and Agency. Depuis 1990, le Programme des Nations Unies pour le développement ... Gender and Natural Resource Management : Livelihoods, Mobility and Interventions. Depuis dix ans aucun ouvrage n'a jeté un regard synoptique sur l'axe ...

  10. Kenya | Page 29 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Read more about East African GEOHealth hub for preventing environmental and occupational health risks. Langue English. Read more about Accroître les possibilités économiques pour les jeunes dans les secteurs du poisson et de la volaille au Kenya (CultivAf). Langue French. Read more about The Alliance to Scale ...

  11. Publications | Page 40 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Amérique du Nord et de l'Europe pour inclure maintenant un plus grand nombre d'établissements de recherche africains. Activité antérieure : Le CRDI au Congrès mondial sur la santé publique 2015. Le 14e Congrès mondial sur la santé publique ...

  12. Publications | Page 181 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Economic Liberalization and Political Violence : Utopia or Dystopia ? Un ouvrage essentiel pour quiconque souhaite comprendre les conflits et le développement au XXIe siècle. James Putzel, Crisis States Research Centre, London School of Economics. Alors que certains voient en la mondialisation un outil de ...

  13. Publications | Page 186 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Economic Liberalization and Political Violence : Utopia or Dystopia ? Un ouvrage essentiel pour quiconque souhaite comprendre les conflits et le développement au XXIe siècle. James Putzel, Crisis States Research Centre, London School of Economics. Alors que certains voient en la mondialisation un outil de ...

  14. Apprentissage en collaboration pour la cogestion des ressources ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Apprentissage en collaboration pour la cogestion des ressources naturelles en Mongolie. Les prairies et les steppes de la Mongolie abritent actuellement quelque 35 millions de têtes de bétail et 180 ... Outputs. Reports. Collaborative learning for the co-management of natural resources in Mongolia : final technical report ...

  15. Agriculture et environnement | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    appui au développement de la culture du poivre et de la vanille pourrait ... Pour dissuader les gouvernements de ces pays de mettre en oeuvre des politiques visant à réduire la consommation de tabac (telles que la hausse des taxes, ...

  16. Publications | Page 135 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    outils pour le suivi et l'évaluation des initiatives d'adaptation aux effets du changement climatique : étude de cas PADESO; rapport final (restricted access) · Impact de la décharge de Mbeubeuss sur les ressources en eau et sur les sols ...

  17. Publications | Page 27 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Avec nos livres, nos articles, nos publications de recherche et nos études, nous visons à accroître l'impact de nos investissements et à promouvoir la recherche au service du développement. Nous communiquons les ... Transformer les pratiques d'irrigation pour lutter contre la malaria dans le nord du Pérou. Comprendre et ...

  18. De nouveaux vaccins pour animaux pourraient aider davantage d ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    9 juil. 2013 ... Marie-Danielle Smith. Des scientifiques canadiens et africains mettent au point de nouveaux vaccins pour lutter contre les maladies animales et limiter les pertes économiques en Afrique subsaharienne. Certains de ces vaccins pourraient permettre de lutter contre des maladies semblables au Canada.

  19. Droits d'auteur | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Droits d'auteur détenus par le CRDI Sauf indication contraire, les droits d'auteur relatifs aux documents mis en ligne sur le présent site Web sont détenus par le Centre de recherches pour le développement international (CRDI).

  20. À propos du CRDI | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le Centre de recherches pour le développement international (CRDI) finance des travaux de recherche dans les pays en développement afin d'y favoriser la croissance, de réduire la pauvreté et d'impulser des changements positifs à grande échelle.

  1. Publications | Page 102 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La fonte des glaciers en Bolivie est un signe de changement climatique. Scientifiques et agriculteurs combinent des techniques agricoles traditionnelles et la recherche de pointe pour cultiver la terre de façon durable dans les Hautes Andes, où l'équilibre écologique change rapidement.

  2. Publications | Page 106 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    1 Intégration des données météorologiques et du savoir autochtone aux prévisions climatiques saisonnières pour le secteur agricole. Sous la direction de Gina Ziervogel et Alfred Opere, en collaboration avec : Ignitius Chagonda ; Jacob Churi ; Amadou Dieye ; Boris Houenou ; Said Hounkponou ; Eric Kisiangani ; Evans ...

  3. De nouveaux vaccins pour animaux pourraient aider davantage d ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    9 juil. 2013 ... Des scientifiques canadiens et africains mettent au point de nouveaux vaccins pour lutter contre les maladies animales et limiter les pertes économiques en Afrique subsaharienne. Certains de ces vaccins pourraient permettre de lutter contre des maladies semblables au Canada.

  4. The World Bank | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Accueil · Ce que nous faisons · Nos partenaires et initiatives. The World Bank. The World Bank. http://www.worldbank.org/ · Ce que nous faisons · Financement · Ressources · À propos du CRDI. Savoir. Innovation. Solutions. Carrières · Communiquez avec nous · Plan du site. Abonnez-vous à notre bulletin pour recevoir les ...

  5. Uganda : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le présent projet porte sur la création d'emplois pour les jeunes et les femmes en Afrique, en mettant l'accent sur les petites et moyennes entreprises (PME) du secteur du tourisme. Sujet: Gender. Région: Mauritius, Tanzania, Uganda. Programme: Emploi et croissance. Financement total : CA$ 646,600.00. Pourquoi ne se ...

  6. Livres | Page 30 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Asie et du Sud-Est,auraient pu, en principe, partir de la Chine pour se rendre à Singapouren se balançant d'arbre. Maison(s) d'édition : CRDI. ISBN: Épuisé. Couverture du livre Community Assessment of Natural Food Sources of Vitamin A ...

  7. Contrat et confiance pour la gestion des risques de defaillances ...

    African Journals Online (AJOL)

    Penser et mettre en oeuvre de nouveaux mécanismes de gestion des risques de défaillance dans les transactions de financement agricole, qui soient plus efficaces et moins contraignants pour les agriculteurs, constituent l'un des défis majeurs du développement des systèmes financiers ruraux dans les pays en ...

  8. Les femmes se tournent vers les arbres fourragers pour engraisser ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    12 févr. 2018 ... Avec l'appui de la recherche, les femmes d'une commune rurale du Mali savent maintenant comment utiliser les arbres fourragers pour nourrir leurs moutons. Lorsqu'elles ont remplacé le régime alimentaire de leurs moutons, ceux dont la ration incorporait des feuilles de ligneux fourragers ont gagné ...

  9. De nouveaux partenariats pour stimuler l'innovation en agriculture ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Bien que la hausse en flèche du prix des aliments connaisse une certaine accalmie, il en coûte beaucoup plus cher qu'il y a quelques années à bon nombre de consommateurs pauvres des pays en développement pour se nourrir.

  10. Publications | Page 33 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le Centre de recherches pour le développement international (CRDI) appuie le projet Research into Open Educational Resources for Development ou ROER4D (Recherche sur les ressources éducatives libres au service du développement), dont l'objectif est d'améliorer les politiques, les pratiques et la recherche en ...

  11. Publications | Page 34 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le Centre de recherches pour le développement international (CRDI) appuie le projet Research into Open Educational Resources for Development ou ROER4D (Recherche sur les ressources éducatives libres au service du développement), dont l'objectif est d'améliorer les politiques, les pratiques et la recherche en ...

  12. Publications | Page 103 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le FIE 2008 fait avancer le cadre écobiosocial de l'OMS. Le Programme spécial de recherche et de formation concernant les maladies tropicales (TDR) de l'OMS a élaboré le concept du champ « écobiosocial », qui combine les perspectives écologiques, biologiques et sociales « pour mieux.

  13. Recherche | Page 5 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2004-04-22

    Africa is highly vulnerable to climate change, and finding ways to adapt is imperative ... He guides and monitors projects mainly dealing with sea level rise, water ... IDRC's fight against malaria | CRDI - Centre de recherches pour le ... Apr 22, 2004 ... 2004-04-22BACKGROUNDERIn Africa, malaria kills an African child .

  14. Inde | Page 80 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Learning Initiatives on Reforms for Network Economies) is exploring, among other topics, ... Langue English. Il y a huit ans, Loyola Joseph, de la Foundation of Occupational Development (FOOD India), a commencé à se demander comment faire pour ...

  15. Publications | Page 79 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le Sri Lanka mieux préparé aux futurs tsunamis. Les collectivités côtières vulnérables du Sri Lanka sont désormais mieux outillées pour survivre aux tsunamis, cyclones et autres catastrophes naturelles survenant soudainement. Ce degré accru de.

  16. Journal des Sciences Pour l'Ingénieur

    African Journals Online (AJOL)

    Bien au-delà des disciplines Sciences pour l'Ingénieur (Mécanique, Electrique, Civil, Informatique, Chimique…), le journal est ouvert plus largement aux Sciences, de manière à faire écho aux caractères souvent interdisciplinaires des recherches actuelles. Other sites related to this journal: http://www.jspi.sn/ ...

  17. Des outils novateurs pour lutter contre les maladies chroniques au ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    UNWRA). Les populations rurales du Liban ont, quant à elles, accès au système de santé national, mais n'ont souvent pas accès aux moyens de transport ou autres moyens nécessaires pour se rendre aux points de service.

  18. Tendances mondiales et meilleures pratiques pour soutenir les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Tendances mondiales et meilleures pratiques pour soutenir les entrepreneurs : points saillants de la table ronde internationale des économistes en chef. 30 novembre 2017. Image. BDC. Les petites et moyennes entreprises (PME) sont essentielles à la croissance économique et à l'emploi dans le monde entier, mais elles ...

  19. Publications | Page 75 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Étude de l'accessibilité à l'eau potable dans les villages pilotes du projet irrigation de complément et information climatique dans la commune de Kongoussi (restricted access). Le gouvernement burkinabé et ses partenaires ont consenti beaucoup d''efforts en construisant des points d''eau modernes pour atteindre les OMD ...

  20. Appel à propositions pour le concours de 2018 du Programme ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    23 nov. 2017 ... Ces plans peuvent proposer tout un éventail d'activités appuyant les objectifs de recherche et de formation de la proposition et tirer profit de cette occasion de financement pour concevoir un projet de recherche collaboratif international. Le processus de demande de cette occasion de financement ...

  1. Consensus formalisé: recommandations de pratiques cliniques pour ...

    African Journals Online (AJOL)

    Destiné aux praticiens, ce travail collaboratif multinational a pour objectif de fournir 16 recommandations de pratiques cliniques simples, fondées sur les preuves, et adaptées aux conditions de l'exercice médical en Afrique. The Pan African Medical Journal 2016;24. AJOL African Journals Online. HOW TO USE AJOL.

  2. Entretien avec Susan Holtz | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    26 nov. 2010 ... La production de rapports publics est importante, car pour produire des rapports qui veulent vraiment dire quelque chose, il faut préciser clairement les ... politiques et écologiques idéalistes avec ce que les êtres humains semblent vouloir en réalité comme croissance économique, automobiles et biens ...

  3. uganda : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le présent projet porte sur la création d'emplois pour les jeunes et les femmes en Afrique, en mettant l'accent sur les petites et moyennes entreprises (PME) du secteur du tourisme. Région: Mauritius, Tanzania, Uganda. Programme: Employment and Growth. Financement total : CA$ 646,600.00. Pourquoi ne se battent-ils ...

  4. Publications | Page 2 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Tendances mondiales et meilleures pratiques pour soutenir les entrepreneurs : points saillants de la table ronde internationale des économistes en chef. Les petites et moyennes entreprises (PME) sont essentielles à la croissance économique et à l'emploi dans le monde entier, mais elles ont une incidence encore plus ...

  5. Publications | Page 74 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    environnement en Angola, un bénéficiaire de subvention de longue date du CRDI conjugue des observations obtenues par satellite et des données... Petits bassins individuels pour l'irrigation de complément : analyse diagnostique des bassins ...

  6. Publications | Page 50 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... développement persistants auxquels elle est confrontée, l'Afrique abrite certaines des économies qui connaissent la croissance la plus rapide au monde. L'entrepreneuriat y... Favoriser l'entrepreneuriat. Pour comprendre les entrepreneurs d'aujourd'hui, il suffit de s'en remettre au Global Entrepreneurship Monitor (GEM).

  7. Publications | Page 65 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Quels sont les liens entre l'eau et l'énergie au regard des changements climatiques ? Des technologies d'énergies renouvelables décentralisées pour les services d'approvisionnement en eau pourraient‑elles aider les collectivités pauvres des pays en développement à s'adapter plus efficacement aux changements.

  8. Publications | Page 73 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Quels sont les liens entre l'eau et l'énergie au regard des changements climatiques ? Des technologies d'énergies renouvelables décentralisées pour les services d'approvisionnement en eau pourraient‑elles aider les collectivités pauvres des pays en développement à s'adapter plus efficacement aux changements.

  9. Inde | Page 90 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    However, as entrepreneurs scour the world in search of new commodities, a voice of dissent is growing and striving to be heard. ... entreprises doivent se faire concurrence pour survivre, prendre de l'expansion et occuper une part du marché, les bibliothécaires et les professionnels de l'information doivent jouer un rôle plus ...

  10. Des statistiques essentielles | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    un programme de recherche sur le terrain mené pour le compte du Centre international de recherche sur les maladies diarrhéiques. Au début, les accoucheuses traditionnelles faisaient état de variations démographiques hebdomadaires dans ...

  11. Guatemala : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    'allier pour éradiquer la maladie de Chagas en Amérique centrale. Projet. Les pertes économiques mondiales causées par la maladie de Chagas sont estimées à 7 milliards d'USD par an. Région: Guatemala. Programme: Food, Environment ...

  12. Initiative Think tank | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'ITT est le fruit d'un partenariat regroupant cinq bailleurs de fonds. Lancée en 2008, l'ITT est administrée par le Centre de Recherches pour le Développement International (CRDI), un organisme canadien.

  13. Ce que nous faisons | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le CRDI appuie des travaux de recherche dans les pays en voie de développement en vue de produire un changement réel et durable. Ce savoir peut servir d'outil pour résoudre des problèmes mondiaux urgents. Nous partageons ce savoir avec les autres en :

  14. Inde | Page 89 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    , mettant en péril la vie humaine et les écosystèmes. De plus, ils sont souvent sources de conflit entre populations et industrie. En adoptant une approche écosystémique globale pour examiner les intérêts divergents et leurs conséquences, ...

  15. Eau, terre et vie : Communication participative pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    6 févr. 2007 ... Eau, terre et vie : Communication participative pour le développement et gestion des ressources naturelles ... Le CRDI investit dans des solutions locales aux problèmes auxquels l'Inde est confrontée, comme le stress thermique, la gestion de l'eau et les migrations liées aux changements climatiques.

  16. Recherche | Page 5 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Gestion des risques climatiques pour la planification de l'agriculture ... La province du Cap-Occidental est le secteur le plus rentable sur le plan de l' agriculture en Afrique du Sud et contribue de manière importante à la balance des .

  17. Publications | Page 29 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Coutumes et croyances favorables et defavorables pour une gestion inclusive de la securite (open access). L''étude objective des sources et des données ethnographiques montre que la culture dominante dans la zone Ouest africaine, se définit en termes de dialogue, de compromis, de coexistence et de paix. Dans cette ...

  18. Publications | Page 172 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    E-Commerce in the Asian Context : Selected Case Studies. Le commerce électronique en Asie retient beaucoup l'attention en raison de la prolifération des connexions Internet et des technologies connexes dans la région. Face à cette tendance, le Centre de recherches pour le développement international (.

  19. Publications | Page 173 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    E-Commerce in the Asian Context : Selected Case Studies. Le commerce électronique en Asie retient beaucoup l'attention en raison de la prolifération des connexions Internet et des technologies connexes dans la région. Face à cette tendance, le Centre de recherches pour le développement international (.

  20. Publications | Page 156 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Evictions and the Right to Housing : Experience from Canada, Chile, the Dominican Republic, South Africa, and South Korea. Le droit au logement est un droit fondamental de la personne réaffirmé en juin 1996 lorsque les gouvernements du monde entier se sont réunis à Istanbul, en Turquie pour Habitat II – la deuxième ...

  1. Pouring and running a protein gel by reusing commercial cassettes.

    Science.gov (United States)

    Hwang, Alexander C; Grey, Paris H; Cuddy, Katrina; Oppenheimer, David G

    2012-02-12

    The evaluation of proteins using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis is a common technique used by biochemistry and molecular biology researchers. For laboratories that perform daily analyses of proteins, the cost of commercially available polyacrylamide gels (~$10/gel) can be considerable over time. To mitigate this cost, some researchers prepare their own polyacrylamide gels. Traditional methods of pouring these gels typically utilize specialized equipment and glass gel plates that can be expensive and preclude pouring many gels and storing them for future use. Furthermore, handling of glass plates during cleaning or gel pouring can result in accidental breakage creating a safety hazard, which may preclude their use in undergraduate laboratory classes. Our protocol demonstrates how to pour multiple protein gels simultaneously by recycling Invitrogen Nupage Novex minigel cassettes, and inexpensive materials purchased at a home improvement store. This economical and streamlined method includes a way to store the gels at 4°C for a few weeks. By re-using the plastic gel cassettes from commercially available gels, labs that run frequent protein gels can save significant costs and help the environment. In addition, plastic gel cassettes are extremely resistant to breakage, which makes them ideal for undergraduate laboratory classrooms.

  2. Les femmes arabes toujours en lutte pour leurs droits | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    29 janv. 2013 ... Une campagne ayant mené à la reconnaissance juridique des droits en matière de nationalité des femmes arabes dans neuf pays et territoires constitue une source d'inspiration et de solutions stratégiques pour les femmes qui, un peu partout au Moyen-Orient, se heurtent à une discrimination croissante.

  3. Publications | Page 133 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le 28 juin 2006, le domaine de programme Innovation, politique et science (IPS) a présenté au Conseil des gouverneurs du CRDI un plan stratégique pour orienter la phase initiale (2006 2011) des recherches ... Simultanément, il explore certaines des options permettant d'envisager la revitalisation de ce processus.

  4. Shell model calculations for the mass 18 nuclei in the sd-shell

    International Nuclear Information System (INIS)

    Hamoudi, A.

    1997-01-01

    A simple effective nucleon-nucleon interaction for shell model calculations in the sd-shell is derived from the Reid soft-core potential folded with two-body correlation functions which take account of the strong short-range repulsion and large tensor component in the Reid force. Calculations of binding energies and low-lying spectra are performed for the mass A=18 with T=0 and 1 nuclei using this interaction. The results of this shell model calculations show a reasonable agreement with experiment

  5. Development of Mortar Simulator with Shell-In-Shell System – Problem of External Ballistics

    Directory of Open Access Journals (Sweden)

    A. Fedaravicius

    2007-01-01

    Full Text Available The shell-in-shell system used in the mortar simulator raises a number of non-standard technical and computational problems starting from the requirement to distribute the propelling blast energy between the warhead and the ballistic barrel, finishing with the requirement that the length of warhead's flight path must be scaled to combat shell firing tables. The design problem of the simulator is split into two parts – the problem of external ballistics where the initial velocities of the warhead must be determined, and the problem of internal ballistics – where the design of the cartridge and the ballistic barrel must be performed.

  6. Interelectron correlations in photoionization of outer shells near inner shell thresholds

    International Nuclear Information System (INIS)

    Amusia, M Ya; Chernysheva, L V; Drukarev, E G

    2015-01-01

    We have studied the role of virtual excitations of inner shells upon outer shell photoionization. The calculations were performed in the frames of the Random Phase Approximation with Exchange (RPAE) and its generalized version GRPAE that take into account variation of the atomic field due to electron elimination and the inner vacancies decay. We apply both analytic approximation and numeric computations. The results are presented for 3p electrons in Ar and for 4d-electrons in Pd near inner shells thresholds. The effect considered proved to be quite noticeable. (paper)

  7. Analysis of the DWPF glass pouring system using neural networks

    International Nuclear Information System (INIS)

    Calloway, T.B. Jr.; Jantzen, C.M.

    1997-01-01

    Neural networks were used to determine the sensitivity of 39 selected Melter/Melter Off Gas and Melter Feed System process parameters as related to the Defense Waste Processing Facility (DWPF) Melter Pour Spout Pressure during the overall analysis and resolution of the DWPF glass production and pouring issues. Two different commercial neural network software packages were used for this analysis. Models were developed and used to determine the critical parameters which accurately describe the DWPF Pour Spout Pressure. The model created using a low-end software package has a root mean square error of ± 0.35 inwc ( 2 = 0.77) with respect to the plant data used to validate and test the model. The model created using a high-end software package has a R 2 = 0.97 with respect to the plant data used to validate and test the model. The models developed for this application identified the key process parameters which contribute to the control of the DWPF Melter Pour Spout pressure during glass pouring operations. The relative contribution and ranking of the selected parameters was determined using the modeling software. Neural network computing software was determined to be a cost-effective software tool for process engineers performing troubleshooting and system performance monitoring activities. In remote high-level waste processing environments, neural network software is especially useful as a replacement for sensors which have failed and are costly to replace. The software can be used to accurately model critical remotely installed plant instrumentation. When the instrumentation fails, the software can be used to provide a soft sensor to replace the actual sensor, thereby decreasing the overall operating cost. Additionally, neural network software tools require very little training and are especially useful in mining or selecting critical variables from the vast amounts of data collected from process computers

  8. COMPUTATIONAL INVESTIGATIONS OF DEFORMATED STRESS STATE OF THE SHELL ROOF

    Directory of Open Access Journals (Sweden)

    Yarov Vaycheslav Alekseevich

    2012-09-01

    Full Text Available Computational investigations of the new design concept of monolithic shell roof of the construction were made. Theoretical data of deformated stress state of the shell roof is found.

  9. 1051 Ergs: The Evolution of Shell Supernova Remnants

    National Research Council Canada - National Science Library

    Jones, T. W; Rudnick, Lawrence; Jun, Byung-Il; Borkowski, Kazimierz J; Dubner, Gloria; Frail, Dale A; Kang, Hyesung; Kassim, Namir E; McCray, Richard

    1997-01-01

    Although the title points only to classical, shell SNR structures, the workshop also considered dynamical issues involving X-ray filled composite remnants and pulsar-driven shells, such as that in the Crab Nebula...

  10. Algorithmes et architectures pour ordinateurs quantiques supraconducteurs

    Science.gov (United States)

    Blais, A.

    2003-09-01

    'utilisation de qubits basés sur les jonctions Josephson. On présente entre autres une approche originale pour l'interaction entre qubits. Cette approche est très générale puisqu'elle peut être appliquée à différents designs de qubits. Finalement, on s'intéresse à la lecture des qubits supraconducteurs de flux. Le détecteur suggéré ici a l'avantage de pouvoir être découplé du qubit lorsqu'il n'y a pas de mesure en cours.

  11. Bearing capacity of shell strip footing on reinforced sand

    OpenAIRE

    W.R. Azzam; A.M. Nasr

    2015-01-01

    In this paper, the ultimate load capacities of shell foundations on unreinforced and reinforced sand were determined by laboratory model tests. A series of loading tests were carried out on model shell footing with and without single layer of reinforcement. The tests were done for shell foundation at different shell embedment depth and subgrade density. The results were compared with those for flat foundations without reinforcement. The model test results were verified using finite element an...

  12. Analysis of flexible layered shallow shells on elastic foundation

    Science.gov (United States)

    Stupishin, L.; Kolesnikov, A.; Tolmacheva, T.

    2017-05-01

    This paper contains numerical analysis of a layered geometric nonlinear flexible shallow shell based on an elastic foundation. Rise of arch in the center of the shell, width, length and type of support are given. The design variable is taken to be the thickness of the shallow shell, the form of the middle surface forming and the characteristic of elastic foundations. Critical force coefficient and stress of shells are calculated by Bubnov-Galerkin. Stress, characteristic of elastic foundations - thickness dependence are presented.

  13. Multiple inner shell vacancies in laser-irradiated Au plasma

    International Nuclear Information System (INIS)

    Kiyokawa, S.; Yabe, T.; Miyanaga, N.; Okada, K.; Hasegawa, H.; Mochizuki, T.; Yamanaka, T.; Yamanaka, C.; Kagawa, T.

    1985-01-01

    The forteen line spectra in 3 -- 4 keV from laser-irradiated Au plasma were identified by the relativistic Hartree-Fock-Slater method and were attributed to the multiple inner-shell vacancies in 3psub(1/2) (or 3psub(3/2)) shell and N shell. The spliting of two groups of lines was about 400 eV and was found to be due to the spin-orbit interaction in 3p shell. (author)

  14. BOWOOSS: bionic optimized wood shells with sustainability

    Science.gov (United States)

    Pohl, Göran

    2011-04-01

    In architecture, shell construction is used for the most efficient, large spatial structures. Until now the use of wood rather played a marginal role, implementing those examples of architecture, although this material offers manifold advantages, especially against the background of accelerating shortage of resources and increasing requirements concerning the energy balance. Regarding the implementation of shells, nature offers a wide range of suggestions. The focus of the examinations is on the shells of marine plankton, especially of diatoms, whose richness in species promises the discovery of entirely new construction principles. The project is targeting at transferring advantageous features of these organisms on industrial produced, modular wood shell structures. Currently a transfer of these structures in CAD - models is taking place, helping to perform stress analysis by computational methods. Micro as well as macro structures are the subject of diverse consideration, allowing to draw the necessary conclusions for an architectural design. The insights of these tests are the basis for the development of physical models on different scales, which are used to verify the different approaches. Another important aim which is promoted in the project is to enhance the competitiveness of timber construction. Downsizing of the prefabricated structural elements leads to considerable lower transportation costs as abnormal loads can be avoided as far as possible and means of transportation can be loaded with higher efficiency so that an important contribution to the sustainability in the field of architecture can also be made.

  15. DETERMINANTS OF ADOPTION OF WHITE EGG SHELLED ...

    African Journals Online (AJOL)

    This Paper centres on the factors influencing the adoption of white egg shelled layers among poultry farmers in Ogun State, Nigeria. It relied on the primary data collected from 96 randomly selected poultry farmers from five local government areas of Ogun state, Nigeria. The analytical techniques used are descriptive ...

  16. Nucleon knockout: off-shell effects

    International Nuclear Information System (INIS)

    Stephenson, G.J. Jr.

    1977-01-01

    The effect of the off-energy-shell extrapolation of the proton-proton scattering amplitude on the analysis of (p,2p) reactions is discussed. In particular, the range of expected variations in this extrapolation is explored and the possibility of using knock-out reactions to limit models of the p-p amplitude is studied

  17. Assessment Of Shell Petroleum Development Company Extension ...

    African Journals Online (AJOL)

    The study assessed Shell Petroleum Development Company Extension Services in Etche Local Government Area of Rivers State, Nigeria. Data were gathered form four categories of respondents drawn from the Company\\'s staff and the communities. A total of 180 respondents participated in the study. means scores and ...

  18. Conceptual Design Tool for Concrete Shell Structures

    DEFF Research Database (Denmark)

    Holst, Malene Kirstine; Kirkegaard, Poul Henning

    2011-01-01

    This paper focuses on conceptual tools for concrete shell structures when working within the span of performance-based design and computational morphogenesis. The designer, referred to as the Architect-Engineer, works through several iterations parallel with aesthetic, functional and technical...

  19. On Newton’s shell theorem

    Science.gov (United States)

    Borghi, Riccardo

    2014-03-01

    In the present letter, Newton’s theorem for the gravitational field outside a uniform spherical shell is considered. In particular, a purely geometric proof of proposition LXXI/theorem XXXI of Newton’s Principia, which is suitable for undergraduates and even skilled high-school students, is proposed. Minimal knowledge of elementary calculus and three-dimensional Euclidean geometry are required.

  20. Cherry Scallop Shell Moth Pest Alert

    Science.gov (United States)

    John Omer; Debra Allen-Reid

    1996-01-01

    The cherry scallop shell moth, Hydria prunivorata (Ferguson) is a defoliator of black cherry, and occasional other native cherries throughout its range in eastern North America. The moth?s name is derived from the pattern of alternating dark and light scalloped lines on the wings. The adults which emerge from late May to early August, have a wingspread of about 37mm....

  1. Triggered star formation in expanding shells

    Czech Academy of Sciences Publication Activity Database

    Ehlerová, Soňa; Palouš, Jan

    2002-01-01

    Roč. 330, č. 4 (2002), s. 1022-1026 ISSN 0035-8711 R&D Projects: GA AV ČR IAA3003705; GA AV ČR KSK1048102 Institutional research plan: CEZ:AV0Z1003909 Keywords : interstellar medium * star formation * HI shells Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.671, year: 2002

  2. DNA nanoparticles with core-shell morphology.

    Science.gov (United States)

    Chandran, Preethi L; Dimitriadis, Emilios K; Lisziewicz, Julianna; Speransky, Vlad; Horkay, Ferenc

    2014-10-14

    Mannobiose-modified polyethylenimines (PEI) are used in gene therapy to generate nanoparticles of DNA that can be targeted to the antigen-presenting cells of the immune system. We report that the sugar modification alters the DNA organization within the nanoparticles from homogenous to shell-like packing. The depth-dependent packing of DNA within the nanoparticles was probed using AFM nano-indentation. Unmodified PEI-DNA nanoparticles display linear elastic properties and depth-independent mechanics, characteristic of homogenous materials. Mannobiose-modified nanoparticles, however, showed distinct force regimes that were dependent on indentation depth, with 'buckling'-like response that is reproducible and not due to particle failure. By comparison with theoretical studies of spherical shell mechanics, the structure of mannobiosylated particles was deduced to be a thin shell with wall thickness in the order of few nanometers, and a fluid-filled core. The shell-core structure is also consistent with observations of nanoparticle denting in altered solution conditions, with measurements of nanoparticle water content from AFM images, and with images of DNA distribution in Transmission Electron Microscopy.

  3. UHPFRC in large span shell structures

    NARCIS (Netherlands)

    Ter Maten, R.N.; Grunewald, S.; Walraven, J.C.

    2013-01-01

    Ultra-High Performance Fibre-Reinforced Concrete (UHPFRC) is an innovative concrete type with a high compressive strength and a far more durable character compared to conventional concrete. UHPFRC can be applied in structures with aesthetic appearance and high material efficiency. Shell structures

  4. Are Pericentric Inversions Reorganizing Wedge Shell Genomes?

    Directory of Open Access Journals (Sweden)

    Daniel García-Souto

    2017-12-01

    Full Text Available Wedge shells belonging to the Donacidae family are the dominant bivalves in exposed beaches in almost all areas of the world. Typically, two or more sympatric species of wedge shells differentially occupy intertidal, sublittoral, and offshore coastal waters in any given locality. A molecular cytogenetic analysis of two sympatric and closely related wedge shell species, Donax trunculus and Donax vittatus, was performed. Results showed that the karyotypes of these two species were both strikingly different and closely alike; whilst metacentric and submetacentric chromosome pairs were the main components of the karyotype of D. trunculus, 10–11 of the 19 chromosome pairs were telocentric in D. vittatus, most likely as a result of different pericentric inversions. GC-rich heterochromatic bands were present in both species. Furthermore, they showed coincidental 45S ribosomal RNA (rRNA, 5S rRNA and H3 histone gene clusters at conserved chromosomal locations, although D. trunculus had an additional 45S rDNA cluster. Intraspecific pericentric inversions were also detected in both D. trunculus and D. vittatus. The close genetic similarity of these two species together with the high degree of conservation of the 45S rRNA, 5S rRNA and H3 histone gene clusters, and GC-rich heterochromatic bands indicate that pericentric inversions contribute to the karyotype divergence in wedge shells.

  5. Symplectic symmetry in the nuclear shell model

    NARCIS (Netherlands)

    French, J.B.

    The nature of the general two-particle interaction which is compatible with symplectic symmetry in the jj coupling shell model is investigated. The essential result is that, to within an additive constant and an additive multiple of T2, the interaction should have the form of a sum of scalar

  6. William Hayes and His Pallanza Bomb Shell

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 16; Issue 10. William Hayes and His Pallanza Bomb Shell. R Jayaraman. General Article Volume 16 Issue 10 October 2011 pp 911-921. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/016/10/0911-0921 ...

  7. Monitoring of the Phenix reactor conic shell

    International Nuclear Information System (INIS)

    Poidevin, C.; Gros, J.

    2000-01-01

    The Safety Authority (DSIN) asked the monitoring of Phenix reactor core support structures. In this framework the cea developed a method to control by ultrasonic testing the welded joints of the core support shell, in stainless steel-316L, immersed in sodium. The method and the inspection are presented in this paper. (A.L.B.)

  8. Magnetic core-shell silica particles

    NARCIS (Netherlands)

    Claesson, E.M.

    2007-01-01

    This thesis deals with magnetic silica core-shell colloids and related functionalized silica structures. Synthesis routes have been developed and optimized. The physical properties of these colloids have been investigated, such as the magnetic dipole moment, dipolar structure formation and

  9. Hydrodynamic experiments on dacryoconarid shell telescoping

    Czech Academy of Sciences Publication Activity Database

    Hladil, Jindřich; Šimčík, Miroslav; Růžička, Marek; Kulaviak, Lukáš; Lisý, Pavel

    2014-01-01

    Roč. 47, č. 3 (2014), s. 376-396 ISSN 0024-1164 R&D Projects: GA ČR GAP210/10/2351 Institutional support: RVO:67985831 ; RVO:67985858 Keywords : dacryoconarid shells * experimental fluid mechanics * narrow cones * Palaeozoic * telescoping Subject RIV: DB - Geology ; Mineralogy; CI - Industrial Chemistry, Chemical Engineering (UCHP-M) Impact factor: 1.454, year: 2014

  10. Conical shell edge disturbance : An engineer's derivation

    NARCIS (Netherlands)

    Blaauwendraad, J.; Hoefakker, JH

    2016-01-01

    Because a rigorous bending theory for thin shells of revolution is complicated, attempts have been made for reliable approximations of the edge disturbance problem under axisymmetric loading. A well-known one was published by Geckeler [1, 2], who obtained his approximation by mathematical

  11. On-Shell Methods in Perturbative QCD

    International Nuclear Information System (INIS)

    Bern, Zvi; Dixon, Lance J.; Kosower, David A.

    2007-01-01

    We review on-shell methods for computing multi-parton scattering amplitudes in perturbative QCD, utilizing their unitarity and factorization properties. We focus on aspects which are useful for the construction of one-loop amplitudes needed for phenomenological studies at the Large Hadron Collider

  12. Optimised photocatalytic hydrogen production using core–shell AuPd promoters with controlled shell thickness

    DEFF Research Database (Denmark)

    Jones, Wilm; Su, Ren; Wells, Peter

    2014-01-01

    The development of efficient photocatalytic routines for producing hydrogen is of great importance as society moves away from energy sources derived from fossil fuels. Recent studies have identified that the addition of metal nanoparticles to TiO2 greatly enhances the photocatalytic performance...... of these materials towards the reforming of alcohols for hydrogen production. The core–shell structured Au–Pd bimetallic nanoparticle supported on TiO2 has being of interest as it exhibited extremely high quantum efficiencies for hydrogen production. However, the effect of shell composition and thickness...... on photocatalytic performance remains unclear. Here we report the synthesis of core–shell structured AuPd NPs with the controlled deposition of one and two monolayers (ML) equivalent of Pd onto Au NPs by colloidal and photodeposition methods. We have determined the shell composition and thickness...

  13. Exciton states and optical absorption in core/shell/shell spherical quantum dot

    Science.gov (United States)

    Hayrapetyan, D. B.; Baghdasaryan, D. A.; Kazaryan, E. M.; Pokutnyi, S. I.; Sarkisyan, H. A.

    2018-04-01

    The exciton states in core/shell/shell spherical quantum dot with three-dimensional Winternitz-Smorodinsky confinement potential are considered. The problem is discussed in the framework of adiabatic approximation when the heavy hole is situated in the effective potential well caused by the electron. The interband optical transitions caused by incident light polarized in z-direction have been considered in such systems. The oscillator strengths and selection rules for the quantum transitions have been obtained. The ensemble of quantum dots and their size dispersion have been taken into account in the calculations. The Gaussian distribution has been chosen to describe the size dispersion of the core/shell/shell quantum dots thickness. The dependence of the absorption coefficient and photoluminescence spectra on the energy of incident light of interband transitions have been obtained.

  14. Precipitation of iron in windopane oyster shells by marine shell-boring cyanobacteria

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.; Rao, V.P.; Iyer, S.D.

    electron microscopy, suggested the presence of iron as iron oxides. The cyanobacteria from such black shells were cultured in enriched seawater medium. In this medium also they precipitated iron as confirmed by Prussian blue reaction. They were identified...

  15. Problems with tunneling of thin shells from black holes

    Indian Academy of Sciences (India)

    the manifolds inside and outside the shell. In this paper we choose Eddington–. Finkelstein coordinates. The coordinates and transformation laws are explained in. Appendix B and here we summarize the equations of motion. As explained in §4 we use the symbol ⊘ to mean + for outgoing shells and − for ingoing shells.

  16. Initial Single-Shell Tank Retrieval System mission analysis report

    International Nuclear Information System (INIS)

    Hertzel, J.S.

    1996-03-01

    This document provides the mission analysis for the Initial Single-Shell Tank Retrieval System task, which supports the Single-Shell Tank Waste Retrieval Program in its commitment to remove waste from single-shell tanks for treatment and final closure

  17. From Bash to Z shell in 5 min

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    Chances are you're spending a good amount of your time working on a shell. While Bash is the standard shell on Linux, some alternatives exist. I'll show you how to switch to one of them (Z shell) and what benefits come with it.

  18. Vibrations of thin piezoelectric shallow shells: Two-dimensional ...

    Indian Academy of Sciences (India)

    In this paper we consider the eigenvalue problem for piezoelectric shallow shells and we show that, as the thickness of the shell goes to zero, the eigensolutions of the three-dimensional piezoelectric shells converge to the eigensolutions of a two-dimensional eigenvalue problem.

  19. Properties of Activated Carbon Prepared from Coconut Shells in ...

    African Journals Online (AJOL)

    Materials commonly used for preparation of activated carbons include coal and coconut shells. Ghana generates over 30,000 tonnes of coconut shells annually from coconut oil processing activities but apart from a small percentage of the shells, which is burned as fuel, the remaining is usually dumped as waste.

  20. Optical properties of spherical and oblate spheroidal gold shell colloids

    NARCIS (Netherlands)

    Penninkhof, J.J.; Moroz, A.; van Blaaderen, A.; Polman, A.

    2008-01-01

    The surface plasmon modes of spherical and oblate spheroidal core−shell colloids composed of a 312 nm diameter silica core and a 20 nm thick Au shell are investigated. Large arrays of uniaxially aligned core−shell colloids with size aspect ratios ranging from 1.0 to 1.7 are fabricated using a novel

  1. Vibrations of thin piezoelectric shallow shells: Two-dimensional ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    In this paper we consider the eigenvalue problem for piezoelectric shallow shells and we show that, as the thickness of the shell goes to zero, the eigensolutions of the three-dimensional piezoelectric shells converge to the eigensolutions of a two- dimensional eigenvalue problem. Keywords. Vibrations; piezoelectricity ...

  2. Shell utilization and morphometries of the hermit crab Diogenes ...

    African Journals Online (AJOL)

    Fecundity, shell utilization, and crab and associated shell morphometries were investigated for the hermit crab Diogenes brevirostris collected from three intertidal sites in the eastern Cape. The relationship between crab fresh mass and egg number was linear. D. brevirostris was found to occupy 33 gastropod shell species ...

  3. 49 CFR 230.26 - Tensile strength of shell plates.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Tensile strength of shell plates. 230.26 Section... Appurtenances Strength of Materials § 230.26 Tensile strength of shell plates. When the tensile strength of steel or wrought-iron shell plates is not known, it shall be taken at 50,000 psi for steel and 45,000...

  4. Spatial distribution of dust in the shell elliptical NGC 5982

    NARCIS (Netherlands)

    del Burgo, C.; Carter, D.; Sikkema, G.

    Aims. Shells in Ellipticals are peculiar faint sharp edged features that are thought to be formed by galaxy mergers. We determine the shell and dust distributions, and colours of a well-resolved shell and the underlying galaxy in NGC 5982, and compare the spatial distributions of the dust and gas

  5. Exploratory study of crushed periwinkle shell as partial replacement ...

    African Journals Online (AJOL)

    The purpose of the study is to explore the possibility of turning waste to wealth. A significant factor is that concrete will be produced cheaper in areas with large population of periwinkle shells, while the environment that these periwinkle shells are usually dumped will become better protected. Keywords: periwinkle shell, river ...

  6. Porous Core-Shell Nanostructures for Catalytic Applications

    Science.gov (United States)

    Ewers, Trevor David

    Porous core-shell nanostructures have recently received much attention for their enhanced thermal stability. They show great potential in the field of catalysis, as reactant gases can diffuse in and out of the porous shell while the core particle is protected from sintering, a process in which particles coalesce to form larger particles. Sintering is a large problem in industry and is the primary cause of irreversible deactivation. Despite the obvious advantages of high thermal stability, porous core-shell nanoparticles can be developed to have additional interactive properties from the combination of the core and shell together, rather than just the core particle alone. This dissertation focuses on developing new porous core-shell systems in which both the core and shell take part in catalysis. Two types of systems are explored; (1) yolk-shell nanostructures with reducible oxide shells formed using the Kirkendall effect and (2) ceramic-based porous oxide shells formed using sol-gel chemistry. Of the Kirkendall-based systems, Au FexOy and Cu CoO were synthesized and studied for catalytic applications. Additionally, ZnO was explored as a potential shelling material. Sol-gel work focused on optimizing synthetic methods to allow for coating of small gold particles, which remains a challenge today. Mixed metal oxides were explored as a shelling material to make dual catalysts in which the product of a reaction on the core particle becomes a reactant within the shell.

  7. Shell report 2001; Les personnes, la planete, les profits. Shell rapport 2001

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    In 2001, Shell saw mixed results across the social, environmental and economic spectrum. In order to contribute to the sustainable development, the Group is on track towards meeting its target to reduce greenhouse gas emissions to 10 % below 1990 levels by the end of 2002, although there was a significant increase in spill volumes and greenhouse gas emissions rose. Shell has articulated the business case and defined seven principles of sustainable development for use across the Group in business plans and daily operations: generating robust profitability; delivering value to customers; protecting the environment; managing resources; respecting and safeguarding people; benefiting communities; and working with stakeholders. Key points from the Shell Report include: in the framework of Managing, an independent review of the Shell Nigeria Community Development programme and testing of a human rights assessment tool in Shell South Africa and the implementing of a new Diversity and Inclusiveness Standard; in the framework of the economy the cost improvements of 5,1 billion dollars, ahead of target, the second highest earnings ever in difficult market conditions and the election of Shell top brand for fifth year running by motorists; in the framework of the Social, the safety performance, the avoidance of 100 contracts for incompatibility with Shell Business Principles; in the framework of the Environment, the publication of the Fresh water usage report for the first time, the Greenhouse gas emissions, the increase of spills as a result of a small number of incidents including a pipeline rupture in Nigeria and a well blow out in Oman. The economic, environmental and social data of the Shell Report are externally verified. (A.L.B.)

  8. Ionization of inner shells of atoms taking account of outer shell rearrangement

    International Nuclear Information System (INIS)

    Amusia, M.Ya.

    1977-01-01

    The application of the general many-body theory and methods formulated with its help, in particular, the so-called random phase approximation with exchange (RPAE) and the many-body perturbation theory (MBPT) makes possible a description of ionization processes for many outer and intermediate shells of a number of atoms. This investigation of outer- and intermediate-shell ionization by photons and electrons demonstrates the collective character of these processes and the possibility of describing them by RPAE. 28 references

  9. Searching for nova shells around cataclysmic variables

    Science.gov (United States)

    Sahman, D. I.; Dhillon, V. S.; Knigge, C.; Marsh, T. R.

    2015-08-01

    We present the results of a search for nova shells around 101 cataclysmic variables (CVs), using H α images taken with the 4.2-m William Herschel Telescope (WHT) and the 2.5-m Isaac Newton Telescope Photometric H α Survey of the Northern Galactic Plane (IPHAS). Both telescopes are located on La Palma. We concentrated our WHT search on nova-like variables, whilst our IPHAS search covered all CVs in the IPHAS footprint. We found one shell out of the 24 nova-like variables we examined. The newly discovered shell is around V1315 Aql and has a radius of ˜2.5 arcmin, indicative of a nova eruption approximately 120 yr ago. This result is consistent with the idea that the high mass-transfer rate exhibited by nova-like variables is due to enhanced irradiation of the secondary by the hot white dwarf following a recent nova eruption. The implications of our observations for the lifetime of the nova-like variable phase are discussed. We also examined four asynchronous polars, but found no new shells around any of them, so we are unable to confirm that a recent nova eruption is the cause of the asynchronicity in the white dwarf spin. We find tentative evidence of a faint shell around the dwarf nova V1363 Cyg. In addition, we find evidence for a light echo around the nova V2275 Cyg, which erupted in 2001, indicative of an earlier nova eruption ˜300 yr ago, making V2275 Cyg a possible recurrent nova.

  10. Shell effects and nucleosynthesis of heavy nuclei

    International Nuclear Information System (INIS)

    Farhan, A.R.; Sharma, M.M.

    2005-01-01

    The nuclear shell effects across the magic numbers N = 50, 82 and 126 near the r-process path are crucial to understanding the nucleosynthesis of heavy nuclei. Since nuclei near the r-process path are extremely neutron rich and are not accessible in the laboratory, the current understanding of the nuclear abundances is based much upon extrapolations of various mass formulae. In this talk, we will discuss as to how the shell effects evolve in going from the stability line to the r-process path and towards drip line in the heavy mass region. Within the framework of to the relativistic Hartree-Bogoliubov (RHB) theory with the vector self-coupling of omega meson, it will be shown that the shell effects across N = 82 show a significant decline in going from the r-process path to the drip line, whereas those at N = 126 remain resilient to the change in isospin in going from the r-process path to the neutron drip line. This behaviour of the microscopic RHB calculations is consistent with the recent r-process calculations suggesting that a shell quenching at N = 82 would be useful, however, a quenching is not necessary for reproducing r-process abundances near the peak at A ∼ 190. We will also show that due to an onset of deformation for nuclei above N = 126, an additional stability in some nuclei beyond the neutron drip line is provided. Consequently, this would contribute to r-process nuclear abundances in the third peak. A comparative analysis of shell effects with the microscopic RMF theory and with the macroscopic-microscopic mass formulae shows that the microscopic RMF theory possesses the potential of describing nuclear abundances in the peaks about A ∼ 130 and A ∼ 190. (author)

  11. Protein profiles of hatchery egg shell membrane.

    Science.gov (United States)

    Rath, N C; Liyanage, R; Makkar, S K; Lay, J O

    2016-01-01

    Eggshells which consist largely of calcareous outer shell and shell membranes, constitute a significant part of poultry hatchery waste. The shell membranes (ESM) not only contain proteins that originate from egg whites but also from the developing embryos and different contaminants of microbial and environmental origins. As feed supplements, during post hatch growth, the hatchery egg shell membranes (HESM) have shown potential for imparting resistance of chickens to endotoxin stress and exert positive health effects. Considering that these effects are mediated by the bioactive proteins and peptides present in the membrane, the objective of the study was to identify the protein profiles of hatchery eggshell membranes (HESM). Hatchery egg shell membranes were extracted with acidified methanol and a guanidine hydrochloride buffer then subjected to reduction/alkylation, and trypsin digestion. The methanol extract was additionally analyzed by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS). The tryptic digests were analyzed by liquid chromatography and tandem mass spectrometry (LC-MS-MS) to identify the proteins. Our results showed the presence of several proteins that are inherent and abundant in egg white such as, ovalbumin, ovotransferrin, ovocleidin-116, and lysozyme, and several proteins associated with cytoskeletal, cell signaling, antimicrobial, and catalytic functions involving carbohydrate, nucleic acid, and protein metabolisms. There were some blood derived proteins most likely originating from the embryos and several other proteins identified with different aerobic, anaerobic, gram positive, gram negative, soil, and marine bacterial species some commensals and others zoonotic. The variety of bioactive proteins, particularly the cell signaling and enzymatic proteins along with the diverse microbial proteins, make the HESM suitable for nutritional and biological application to improve post hatch immunity of poultry.

  12. Shell thickness-dependent microwave absorption of core-shell Fe3O4@C composites.

    Science.gov (United States)

    Du, Yunchen; Liu, Wenwen; Qiang, Rong; Wang, Ying; Han, Xijiang; Ma, Jun; Xu, Ping

    2014-08-13

    Core-shell composites, Fe3O4@C, with 500 nm Fe3O4 microspheres as cores have been successfully prepared through in situ polymerization of phenolic resin on the Fe3O4 surface and subsequent high-temperature carbonization. The thickness of carbon shell, from 20 to 70 nm, can be well controlled by modulating the weight ratio of resorcinol and Fe3O4 microspheres. Carbothermic reduction has not been triggered at present conditions, thus the crystalline phase and magnetic property of Fe3O4 micropsheres can be well preserved during the carbonization process. Although carbon shells display amorphous nature, Raman spectra reveal that the presence of Fe3O4 micropsheres can promote their graphitization degree to a certain extent. Coating Fe3O4 microspheres with carbon shells will not only increase the complex permittivity but also improve characteristic impedance, leading to multiple relaxation processes in these composites, thus the microwave absorption properties of these composites are greatly enhanced. Very interestingly, a critical thickness of carbon shells leads to an unusual dielectric behavior of the core-shell structure, which endows these composites with strong reflection loss, especially in the high frequency range. By considering good chemical homogeneity and microwave absorption, we believe the as-fabricated Fe3O4@C composites can be promising candidates as highly effective microwave absorbers.

  13. Risk-based inspection in the Harburg Shell refinery; Risikobasierte Inspektion in der Shell Raffinerie Harburg

    Energy Technology Data Exchange (ETDEWEB)

    Bouwman, H.J. [Deutsche Shell AG, Hamburg (Germany). Raffinerie Harburg; Beck, K. [Technischer Ueberwachungs-Verein Nord e.V., Hamburg (Germany)

    2000-10-01

    Analysis, development and evaluation of new cost reduction strategies is one of the key goals of operators of production systems. For this purpose, Shell Global Solutions International (SGSI), a central service organisation of Shell, developed the concept of 'risk-based inspection' (S-RBI), which is part of their 'risk and reliability management' (RRM). RRM also includes the modeules 'Shell reliability-centered maintenance' (S-RCM) and 'instrumentated protective function' (IPF). [German] Das Analysieren, Entwickeln und Bewerten von neuen Strategien zur Kostensenkung ist eine der Hauptzielsetzungen fuer Betreiber von Produktionsanlagen. Hierfuer hat Shell Global Solutions International (SGSI), eine zentrale Serviceorganisation von Shell, das Konzept der 'Risikobasierten Inspektion' (S-RBI) entwickelt, das ein Teil des 'Risiko- und Zuverlaessigkeits-Managements' (RRM) ist. Neben S-RBI beinhaltet RRM die Module 'Shell-Zuverlaessigkeitsorientierte Wartung' (S-RCM) und Instrumentierte Schutzfunktion (IPF). (orig.)

  14. Scattering amplitudes with off-shell quarks

    Science.gov (United States)

    van Hameren, A.; Kutak, K.; Salwa, T.

    2013-11-01

    We present a prescription to calculate manifestly gauge invariant tree-level scattering amplitudes for arbitrary scattering processes with off-shell initial-state quarks within the kinematics of high-energy scattering. Consider the embedding of the process, in which the off-shell u-quark is replaced by an auxiliary quark qA, and an auxiliary photon γA is added in final state. The momentum flow is as if qA carries momentum k1 and the momentum of γA is identical to 0. γA only interacts via Eq. (3), and qA further only interacts with gluons via normal quark-gluon vertices. qA-line propagators are interpreted as iℓ̸1/(2ℓ1ṡp), and are diagonal in color space. Sum the squared amplitude over helicities of the auxiliary photon. For one helicity, simultaneously assign to the external qA-quark and to γA the spinor and polarization vector |ℓ1], {, {}. Multiply the amplitude with √{-x1k12/2}. For the rest, normal Feynman rules apply.Some remarks are at order. Regarding the momentum flow, we stress, as in [20], that momentum components proportional to k1 do not contribute in the eikonal propagators, and there is a freedom in the choice of the momenta flowing through qA-lines.Regarding the sum over helicities, one might argue that only one of them leads to a non-zero result for given helicity of the final-state quark, but there may, for example, be several identical such quarks in the final state with different helicities.In case of more than one quark in the final state with the same flavor as the off-shell quark, the rules as such admit graphs with γA-propagators. These must be omitted. They do not survive the limit Λ→∞ in the derivation, since the γA-propagators are suppressed by 1/Λ.The rules regarding the qA-line could be elaborated further like in [20], leading to simplified vertices for gluons attached to this line and reducing the numerator of the eikonal propagators to 1. Formulated as above, however, the prescription is more straightforward and

  15. Computed tomographic evaluation of dinosar egg shell integrity

    International Nuclear Information System (INIS)

    Jones, J.C.; Greenberg, W.; Ayers, S.

    1998-01-01

    The purpose of this study was to determine whether computed tomography (CT) could be used to identify hatching holes in partially embedded dinosaur eggs. One Faveololithus and two Dendroolithus eggs were examined using a fourth generation CT scanner. The eggs were partially embedded in a fossilized sediment matrix, with the exposed portion of the shell appearing intact. In CT images of all three eggs, the shells appeared hyperdense relative to the matrix. Hatching holes were visible as large gaps in the embedded portion of the shell, with inwardly displaced shell fragments. It was concluded that CT is an effective technique for nondestructively assessing dinosaur egg shell integrity

  16. [Identification of turtle shell, tortoise plastron and their counterfeit products].

    Science.gov (United States)

    Wang, Z Z; Lin, J M; Ye, G M; Quan, S C; Hu, J H

    2000-05-01

    To identify the commercial Chinese medicines turtle shell and tortoise plastron. Morphological identification and differential thermal analysis (DTA). 2 kinds of counterfeit turtle shell and 3 kinds of counterfeit tortoise plastron were found, and their morphological and DTA identification features were proposed. Sea turtle shells presently on the market are sham commodities of turtle shell, which derive from Lissemys punctata and Pelochelys bibroni indigenous to south Asia, while plastrons of Ocadia sinensis, Chelonia mydas and Lepidochelys olivacea are counterfeit products of tortoise plastron. Turtle shells, tortoise plastrons and their counterfeit products may be exactly distinguished by morphological and DTA features.

  17. Shell Scripting Expert Recipes for Linux, Bash and more

    CERN Document Server

    Parker, Steve

    2011-01-01

    A compendium of shell scripting recipes that can immediately be used, adjusted, and applied The shell is the primary way of communicating with the Unix and Linux systems, providing a direct way to program by automating simple-to-intermediate tasks. With this book, Linux expert Steve Parker shares a collection of shell scripting recipes that can be used as is or easily modified for a variety of environments or situations. The book covers shell programming, with a focus on Linux and the Bash shell; it provides credible, real-world relevance, as well as providing the flexible tools to get started

  18. General off-shell phase equations for local interactions

    International Nuclear Information System (INIS)

    Dolinszky, T.

    1977-11-01

    First order linear differential equations are developed for the completely off-shell phase shift in terms of the cut-off radius of the local two-body interaction. The input to these equations involves on-shell as well as half-off-shell phase functions the latter of which in turn satisfy first order linear differential equations with on-shell phase functions as input. It is concluded that the solution of these new first-order linear differential equations developed within the framework of the standard phase approach is an appropriate means of calculating completely off-shell phase shifts. (D.P.)

  19. Method of fabricating nested shells and resulting product

    Science.gov (United States)

    Henderson, Timothy M.; Kool, Lawrence B.

    1982-01-01

    A multiple shell structure and a method of manufacturing such structure wherein a hollow glass microsphere is surface treated in an organosilane solution so as to render the shell outer surface hydrophobic. The surface treated glass shell is then suspended in the oil phase of an oil-aqueous phase dispersion. The oil phase includes an organic film-forming monomer, a polymerization initiator and a blowing agent. A polymeric film forms at each phase boundary of the dispersion and is then expanded in a blowing operation so as to form an outer homogeneously integral monocellular substantially spherical thermoplastic shell encapsulating an inner glass shell of lesser diameter.

  20. Note on off-shell relations in nonlinear sigma model

    International Nuclear Information System (INIS)

    Chen, Gang; Du, Yi-Jian; Li, Shuyi; Liu, Hanqing

    2015-01-01

    In this note, we investigate relations between tree-level off-shell currents in nonlinear sigma model. Under Cayley parametrization, all odd-point currents vanish. We propose and prove a generalized U(1) identity for even-point currents. The off-shell U(1) identity given in http://dx.doi.org/10.1007/JHEP01(2014)061 is a special case of the generalized identity studied in this note. The on-shell limit of this identity is equivalent with the on-shell KK relation. Thus this relation provides the full off-shell correspondence of tree-level KK relation in nonlinear sigma model.

  1. A Method for Quantifying, Visualising, and Analysing Gastropod Shell Form

    Science.gov (United States)

    Liew, Thor-Seng; Schilthuizen, Menno

    2016-01-01

    Quantitative analysis of organismal form is an important component for almost every branch of biology. Although generally considered an easily-measurable structure, the quantification of gastropod shell form is still a challenge because many shells lack homologous structures and have a spiral form that is difficult to capture with linear measurements. In view of this, we adopt the idea of theoretical modelling of shell form, in which the shell form is the product of aperture ontogeny profiles in terms of aperture growth trajectory that is quantified as curvature and torsion, and of aperture form that is represented by size and shape. We develop a workflow for the analysis of shell forms based on the aperture ontogeny profile, starting from the procedure of data preparation (retopologising the shell model), via data acquisition (calculation of aperture growth trajectory, aperture form and ontogeny axis), and data presentation (qualitative comparison between shell forms) and ending with data analysis (quantitative comparison between shell forms). We evaluate our methods on representative shells of the genera Opisthostoma and Plectostoma, which exhibit great variability in shell form. The outcome suggests that our method is a robust, reproducible, and versatile approach for the analysis of shell form. Finally, we propose several potential applications of our methods in functional morphology, theoretical modelling, taxonomy, and evolutionary biology. PMID:27280463

  2. Ground state instabilities of protein shells are eliminated by buckling.

    Science.gov (United States)

    Singh, Amit R; Perotti, Luigi E; Bruinsma, Robijn F; Rudnick, Joseph; Klug, William S

    2017-11-15

    We propose a hybrid discrete-continuum model to study the ground state of protein shells. The model allows for shape transformation of the shell and buckling transitions as well as the competition between states with different symmetries that characterize discrete particle models with radial pair potentials. Our main results are as follows. For large Föppl-von Kármán (FvK) numbers the shells have stable isometric ground states. As the FvK number is reduced, shells undergo a buckling transition resembling that of thin-shell elasticity theory. When the width of the pair potential is reduced below a critical value, then buckling coincides with the onset of structural instability triggered by over-stretched pair potentials. Chiral shells are found to be more prone to structural instability than achiral shells. It is argued that the well-width appropriate for protein shells lies below the structural instability threshold. This means that the self-assembly of protein shells with a well-defined, stable structure is possible only if the bending energy of the shell is sufficiently low so that the FvK number of the assembled shell is above the buckling threshold.

  3. Optimal designs of mollusk shells from bivalves to snails.

    Science.gov (United States)

    Okabe, Takuya; Yoshimura, Jin

    2017-02-10

    Bivalve, ammonite and snail shells are described by a small number of geometrical parameters. Raup noted that the vast majority of theoretically possible shell forms do not occur in nature. The constraint factors that regulate the biased distribution of natural form have long since been an open problem in evolution. The problem of whether natural shell form is a result of optimization remains unsolved despite previous attempts. Here we solve this problem by considering the scaling exponent of shell thickness as a morphological parameter. The scaling exponent has a drastic effect on the optimal design of shell shapes. The observed characteristic shapes of natural shells are explained in a unified manner as a result of optimal utilization of shell material resources, while isometric growth in thickness leads to impossibly tight coiling.

  4. Quel contrôle de gestion pour les startups ?

    OpenAIRE

    François Meyssonnier

    2015-01-01

    Une étude de huit PME fondées sur la science permet d’identifier les spécificités du contrôle de gestion des startups. Dans les startups émergentes le dirigeant n’utilise que des linéaments de contrôle de gestion essentiellement pour développer son approche cognitive du business model. Dans les startups en croissance le contrôle de gestion a un rôle de garde-fou et les outils de pilotage de la performance sont utilisés essentiellement de façon interactive et pour la prévision. Les principaux ...

  5. Hydrothermal core-shell carbon nanoparticle films: thinning the shell leads to dramatic pH response.

    Science.gov (United States)

    Xia, Fengjie; Pan, Mu; Mu, Shichun; Xiong, Yuli; Edler, Karen J; Idini, Ilaria; Jones, Matthew D; Tsang, Shik Chi; Marken, Frank

    2012-12-05

    Carbon nanoparticles with phenylsulfonate negative surface functionality (Emperor 2000, Cabot Corp.) are coated with positive chitosan followed by hydrothermal carbonization to give highly pH-responsive core-shell nanocarbon composite materials. With optimised core-shell ratio (resulting in an average shell thickness of ca. 4 nm, estimated from SANS data) modified electrodes exhibit highly pH-sensitive resistance, capacitance, and Faradaic electron transfer responses (solution based, covalently bound, or hydrothermally embedded). A shell "double layer exclusion" mechanism is discussed to explain the observed pH switching effects. Based on this mechanism, a broader range of future applications of responsive core-shell nanoparticles are envisaged.

  6. Type I Shell Galaxies as a Test of Gravity Models

    Energy Technology Data Exchange (ETDEWEB)

    Vakili, Hajar; Rahvar, Sohrab [Department of Physics, Sharif University of Technology, P.O. Box 11365-9161, Tehran (Iran, Islamic Republic of); Kroupa, Pavel, E-mail: vakili@physics.sharif.edu [Helmholtz-Institut für Strahlen-und Kernphysik, Universität Bonn, Nussallee 14-16, D-53115 Bonn (Germany)

    2017-10-10

    Shell galaxies are understood to form through the collision of a dwarf galaxy with an elliptical galaxy. Shell structures and kinematics have been noted to be independent tools to measure the gravitational potential of the shell galaxies. We compare theoretically the formation of shells in Type I shell galaxies in different gravity theories in this work because this is so far missing in the literature. We include Newtonian plus dark halo gravity, and two non-Newtonian gravity models, MOG and MOND, in identical initial systems. We investigate the effect of dynamical friction, which by slowing down the dwarf galaxy in the dark halo models limits the range of shell radii to low values. Under the same initial conditions, shells appear on a shorter timescale and over a smaller range of distances in the presence of dark matter than in the corresponding non-Newtonian gravity models. If galaxies are embedded in a dark matter halo, then the merging time may be too rapid to allow multi-generation shell formation as required by observed systems because of the large dynamical friction effect. Starting from the same initial state, the observation of small bright shells in the dark halo model should be accompanied by large faint ones, while for the case of MOG, the next shell generation patterns iterate with a specific time delay. The first shell generation pattern shows a degeneracy with the age of the shells and in different theories, but the relative distance of the shells and the shell expansion velocity can break this degeneracy.

  7. Publications | Page 112 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le sans fil, un outil de gestion des ressources au Mozambique. Au Mozambique, il faut aimer la solitude pour être garde forestier ou garde-chasse, un métier parfois dangereux. L'année dernière, par exemple, un garde-chasse a essuyé le feu d'un braconnier dans une nouvelle réserve naturelle de la.

  8. Shainoor Khoja | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Shainoor Khoja occupe le poste de directrice générale chez Better Business Enterprise, un cabinet d'experts-conseils qui mène des activités à l'échelle internationale et travaille avec de multiples intervenants afin de cerner des occasions d'utiliser la technologie et des modèles d'activités innovateurs pour accroître les ...

  9. Programme de leadership pour favoriser des politiques reliant l ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le nouveau site Web facilitera l'enregistrement des événements démographiques afin d'améliorer l'accès aux services pour tous. Le nouveau site Web et la nouvelle bibliothèque de ressources aideront à améliorer les systèmes d'information et d'enregistrement des faits d'état civil dans les pays en développement.

  10. Communications en cas de catastrophe faisant appel aux TIC pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Communications en cas de catastrophe faisant appel aux TIC pour les collectivités vulnérables des Caraïbes. De récents événements survenus dans les Caraïbes ont mis en relief les insuffisances des mesures régionales et nationales de préparation aux catastrophes. On manque particulièrement de systèmes d'alerte ...

  11. Centre de recherches pour le développement international ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    André Lavoie

    Centre de recherches pour le développement international. Règlement institutionnel. Approuvé par le Comité exécutif de la haute direction. - 1 -. Version 3.0.0 en vigueur le 15-10-2015. Conférences et événements. 1. Contexte. 2. Objectif. 3. Application. 4. Définitions. 5. Rôles et responsabilités. 5.1. Employés. 5.2.

  12. Publications | Page 16 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Grâce au Global Entrepreneurship Monitor (GEM), des chercheurs canadiens et étrangers acquièrent et mettent en commun des connaissances sur les motivations des entrepreneurs et sur la façon de les aider à prospérer. Les gouvernements s'appuient sur leurs constatations pour élaborer des politiques de soutien à ...

  13. Fonds de bourses d'études pour les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La phase II du projet a pour but de mettre en place une nouvelle structure et une nouvelle équipe de rédaction, de présenter des documents de recherche ...... Mali, Sénégal) Gestion et valorisation des déchets d'équipement électronique et informatique en Afrique de l'Ouest Because of their undeveloped condition, African ...

  14. Afrique du Sud | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Dans les Cape Flats, bande de terrain plat qui s'avance dans l'océan à l'extérieur de la ville du Cap, des chercheurs ont cerné de meilleures manières de faire face aux inondations. Leurs travaux ont incité la municipalité à collaborer plus étroitement avec les collectivités et les organismes de la société civile pour trouver ...

  15. Bourses de recherche pour la lutte antitabac en Afrique | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le tabagisme est l'un des principaux facteurs de risque associé à la charge de morbidité croissante liée aux maladies non transmissibles (MNT) dans les pays à faible revenu et pays à revenu intermédiaire. Le Centre pour la lutte antitabac en Afrique (CLATA), qui est situé à l'Université Makerere, en Ouganda, sert de ...

  16. Publications | Page 19 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La Méditerranée est un endroit du monde ou les effets des changements climatiques se font particulièrement sentir. Transfert de responsabilités (2009). Au cours des deux dernières décennies, le Centre de recherches pour le développement international (CRDI) a participé à la mise sur pied et à la fermeture ou au transfert ...

  17. Egypt : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Résultats. Affichage 1 - 10 de 34. Développer une expertise en société civile pour susciter une gouvernance démocratique des forces armées dans les pays arabes ... Négociation de nouvelles relations entre les civils et l'armée dans le monde arabe - la gouvernance politique et économique en transition. Projet. Alors que ...

  18. INSP : initiatives et partenariats | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    10 mai 2011 ... L'Institut Nacional de Salud Pública (INSP) du Mexique a accueilli le Forum international écosanté 2008 (FIE 2008) à Mérida. C'était un rôle tout à fait naturel à bien des égards pour l'INSP.La démarche écosanté est le modus operandi que l'institut aimerait adopter, selon Mario-Henry Rodriguez, directeur ...

  19. Inde | Page 81 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Read more about Markets and Rural Poverty : Upgrading in Value Chains. Langue French. Pour les habitants des secteurs périphériques des villes en plein essor de l'Asie du Sud, l'eau est une ressource rare. Quatre équipes de recherche réparties sur le sous-continent collaborent avec des collectivités en vue de leur ...

  20. Bulletin de BRAS - Janvier 2018 | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    22 janv. 2018 ... Le nouveau site Web facilitera l'enregistrement des événements démographiques afin d'améliorer l'accès aux services pour tous. Le nouveau site Web et la nouvelle bibliothèque de ressources aideront à améliorer les systèmes d'information et d'enregistrement des faits d'état civil dans les pays en ...

  1. Publications | Page 109 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La mondialisation, l'ère de l'information et l'essor de l'économie du savoir transforment profondément les modalités d'acquisition, de diffusion et de transformation du savoir. Il s'ensuit que la production du ... Pour un traitement efficace du VIH/sida dans la province de l'État libre, en Afrique du Sud. En collaboration avec le ...

  2. Publications | Page 222 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Transport et réduction de la pauvreté : étude de cas sur la contribution du secteur des transports à la réalisation des Objectifs du Millénaire pour le Développement (Burkina Faso) (restricted access). Le Burkina Faso, comme la plupart des pays en développement, est confronté à des problèmes liés à l''aggravation de la ...

  3. Chaitali Sinha Administratrice de programme Gouvernance pour l ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    11 mars 2013 ... Chaitali Sinha serait la première à admettre qu'il peut être difficile d'expliquer avec précision en quoi consistent ses fonctions d'administratrice de programme principale au CRDI. Elle a toujours manifesté un vif intérêt pour tout ce qui n'est pas simple; et le développement, ça n'a vraiment rien de simple, ...

  4. Bourses de recherche pour la lutte antitabac en Afrique | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le tabagisme est l'un des principaux facteurs de risque associé à la charge de morbidité croissante liée aux maladies non transmissibles (MNT) dans les pays à faible revenu et pays à revenu intermédiaire. Le Centre pour la lutte antitabac en Afrique (CLATA), qui est situé à l'Université Makerere, en Ouganda, sert de ...

  5. pour les femmes et les enfants vulnérables

    International Development Research Centre (IDRC) Digital Library (Canada)

    Mise au point sur les grossesses chez les adolescentes . 7. La nécessité de meilleures données et de systèmes d'information sanitaire plus solides . 9. Lutte contre les inégalités en matière de santé . 10. Priorités mondiales pour transformer les systèmes de santé dysfonctionnels . 12. Prise en compte des répercussions ...

  6. Renforcement du corpus de connaissances pour des politiques de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Renforcement du corpus de connaissances pour des politiques de propriété intellectuelle qui sont dans l'intérêt public. Des normes de propriété ... sur le travail rémunéré des femmes. Policy in Focus publie un numéro spécial présentant des données probantes sur l'autonomisation des femmes sur le marché du travail.

  7. Économies inclusives | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Pour faire face à ces problèmes et se préparer au prochain cycle de planification, la plus grande agence de planification économique de la Chine a invité la Banque asiatique de développement (BAD) à entreprendre des recherches afin d'éclairer le plan quinquennal 2016-2020 du pays. Read more about Chine : un ...

  8. Publications | Page 123 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La première porte sur un atelier offert à Zanzibar, en Tanzanie, pour illustrer... External Review and Impact Assessment of the African Highlands Initiative (AHI). Sommaire. Il est généralement reconnu que la gestion intégrée des ressources naturelles (GIRN) contribue à l'atteinte du triple objectif de sécurité alimentaire, ...

  9. Ressources pour chercheurs de pays en développement

    International Development Research Centre (IDRC) Digital Library (Canada)

    Mélanie Brunet

    premier volume, mais des embargos (moving walls) allant de 3 à 5 ans sont imposés pour les numéros les plus récents. (voir le contenu disponible). JSTOR est offert .... Gérée par la National Science Foundation of Sri Lanka et développée en collaboration avec INASP, cette base de données donne accès à un contenu ...

  10. Programme de leadership pour favoriser des politiques reliant l ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    En 2005, le réseau mondial Leadership pour l'environnement et le développement (LEAD) Afrique francophone a lancé à Dakar (Sénégal) un programme de renforcement des capacités en approches écosystèmiques de la santé ... An investigation into the determinants of business performance in Francophone Africa.

  11. Des effets durables : Asie | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    6 juin 2014 ... Le Projet hippocampe devient un important protagoniste de la conservation de la faune marine. En savoir plus. L'Initiative pour les micronutriments : des solutions durables à la faim inapparente · L'information améliore les conditions de vie dans les Philippines · De l'eau potable dans les foyers grâce à un ...

  12. Publications | Page 50 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Il découle d'un projet appuyé par le CRDI et mené par le Réseau africain pour le développement intégré (RADI) qui... Les femmes peuvent compter sur les ... Quels mécanismes et stratégies ces pays, consommateurs de produits informatiques et électroniques souvent en fin de cycle, doivent-ils mettre... Préparer l'avenir de ...

  13. SECTION 4 : BUDGET Remarque : Pour en savoir plus sur les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    (anonymous)

    SECTION 4 : BUDGET. Remarque : Pour en savoir plus sur les restrictions budgétaires, consulter l'appel à propositions et la foire aux questions. Inscrire toutes les sommes en dollars canadiens. 4.1 Indiquez toutes les dépenses prévues (en CAD). Inscrire une valeur numérique sans caractères, ni espaces, ni virgules (p. ex ...

  14. Les splenectomies pour rate non traumatique en milieu tropical ...

    African Journals Online (AJOL)

    La pathologie de la rate non traumatique est fréquente et nécessite parfois la réalisation d'une splénectomie préventive, diagnostique ou thérapeutique. But: analyser les indications thérapeutiques des splénectomies pour la rate non traumatique et évaluer les suites opératoires à moyen terme. Méthode: Etude ...

  15. Recommandations pour une agriculture plus écologique respectant ...

    African Journals Online (AJOL)

    Dans le Menabe Central (côte ouest de Madagascar), les paysages forestiers deviennent toujours plus ouverts, le taux de déforestation avoisinant les 0,7 % . La déforestation étant notamment due à des défrichements pour l'agriculture qui est la principale activité de la région, une gestion agricole écologiquement durable ...

  16. Lignes directrices pour la preparation des rapports de recherche

    International Development Research Centre (IDRC) Digital Library (Canada)

    Jean-Claude Dumais

    4. une lettre de votre directeur de thèse ou de mémoire dans laquelle il fait part de ses observations au sujet de vos travaux de recherche sur le terrain. Pour éviter d'alourdir le texte, et comme il est d'usage en français, on a utilisé la forme masculine qui doit, bien entendu, se lire indifféremment au féminin et au masculin.

  17. Publications | Page 60 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    En août 2013, iHub Research a publié les résultats d'une étude subventionnée par le CRDI qui a porté sur la mise au point d'un cadre d'impartition à grande échelle (collecte d'information auprès des citoyens au moyen de plateformes en ligne telles que Twitter, Facebook et les messageries texte) pour suivre une ...

  18. Nouvelle initiative pour atteindre les objectifs mondiaux de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    17 mars 2016 ... Le Centre de recherches pour le développement international (CRDI) et l'Institut de hautes études internationales et du développement à Genève ont établi un partenariat dans le but de jeter les bases d'un programme de soutien qui permettrait aux think tanks des pays en développement d'atteindre les ...

  19. Inde | Page 73 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Il y a plus de vingt ans, Charlie Mayer, exploitant d'un ranch dans le sud du Manitoba et également ministre fédéral de l'Agriculture, est rentré au Canada troublé par ce qu'il avait entendu au cours d'une réunion de l'Organisation des Nations Unies pour l'alimentation et l'agriculture (FAO), à Rome. Read more about Cap ...

  20. Communiquer les découvertes scientifiques pour initier le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La radio est un moyen efficace de faire passer de l'information qui incitera les petits agriculteurs de l'Afrique subsaharienne à adopter des technologies agricoles. Ce projet s'appuiera sur des campagnes radio pour accélérer la mise en oeuvre et l'adoption d'innovations prometteuses en matière d'agriculture et de sécurité ...

  1. Champ ecole paysan, une approche participative pour l'amelioration ...

    African Journals Online (AJOL)

    En vue de favoriser les interactions entre groupes de producteurs pour résoudre les problèmes de production et diffuser les technologies éprouvées, en culture du niébé, trente champs écoles ont été mis en place de 2013 à 2014 au centre sud du Niger avec 600 producteurs dans les départements de Guidan Roumdji, ...

  2. Publications | Page 72 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Nous communiquons les résultats des recherches que nous finançons et offrons du matériel de formation gratuit pour venir en aide aux chercheurs et aux institutions. ... Bien que des progrès aient été récemment réalisés en Afrique subsaharienne, cette région continue d'afficher les taux de mortalité maternelle, de mortalité ...

  3. Publications | Page 164 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Nous communiquons les résultats des recherches que nous finançons et offrons du matériel de formation gratuit pour venir en aide aux chercheurs et aux ... crise de l'eau est imminente en Afrique et au Moyen-Orient, où le volume annuel renouvelable d'eau douce par personne a diminué de moitié depuis 1950 et continue ...

  4. Publications | Page 9 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Nous communiquons les résultats des recherches que nous finançons et offrons du matériel de formation gratuit pour venir en aide aux chercheurs et aux ... Quatre ans après l'effondrement de l'usine textile Rana Plaza au Bangladesh, où plus de 1000 personnes ont péri, un groupe de réflexion de Dacca continue à faire ...

  5. Les programmes du CRDI | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2 nov. 2010 ... La Stratégie générale et Cadre programmatique 2005–2010 du CRDI avait déterminé les objectifs du Centre pour cette période de cinq ans. Il s'agissait de renforcer les capacités de recherche, d'appuyer des recherches débouchant sur de meilleures politiques et pratiques et de favoriser des partenariats ...

  6. Bourse de recherche : Fondements pour l'innovation | CRDI - Centre ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    6 sept. 2017 ... Le boursier travaille à la réalisation de ses objectifs de recherche au sein d'une dynamique équipe d'un programme ou d'une division du CRDI. Le programme Fondements pour l'innovation souhaite mieux comprendre l'environnement qui permet aux chercheurs et aux partenaires d'innover, de tester de ...

  7. Nigeria : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Des solutions fiscales pour une réduction optimale du tabagisme en. Projet. Au cours de la ... Même si des traitements efficaces sont disponibles, bien souvent la dépression périnatale n'est pas traitée, surtout dans les pays à revenu faible et intermédiaire où les spécialistes de la santé mentale se font rares. Région: Nigeria ...

  8. Favoriser l'entrepreneuriat | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    10 avr. 2014 ... Pour comprendre les entrepreneurs d'aujourd'hui, il suffit de s'en remettre au Global Entrepreneurship Monitor (GEM). Lancé en 1999, le projet GEM constitue la plus longue étude sur l'entrepreneuriat au monde; elle s'appuie sur les travaux de plus de 300 chercheurs dans 99 pays. Dans ses enquêtes ...

  9. Solution volumes finis polynomiale par morceaux pour les ...

    African Journals Online (AJOL)

    Nous présentons dans ce papier un concept de solution volumes finis continue pour des problèmes de diffusion-convection avec des données régulières. Nous comparons dans certains cas particuliers la solution proposée avec la solution volumes finis classiques (qui est une fonction constante par morceaux) et la ...

  10. Publications | Page 145 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'Initiative régionale concernant la demande d'eau (WADImena), que finance le CRDI, aide les pays de la région aride du Moyen-Orient et de l'Afrique du Nord à ... urtant, bien que la GDE gagne du terrain auprès des responsables des politiques, elle n'est pas encore assez ancrée sur le plan politique pour être mise en ...

  11. Recherche | Page 5 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Les fermes de Quito, sources d'aliments, d'emplois et d'espoir Le programme d' agriculture urbaine d'abord mis de l'avant par la municipalité de Quito pour ... Économiser l'eau en choisissant les bonnes cultures en Tunisie ... La Tunisie est un pays aux ressources limitées en eau. Bien que l'agriculture ait toujours joué un ...

  12. Tanzanie | Page 11 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Photo : AIMS. Dans la lutte contre le virus Ebola, les mathématiques sont l'arme de Martial Ndeffo. Cet épidémiologiste camerounais aide le ministère de la Santé du Liberia, engagé dans une course contre la montre pour mettre un frein à la propagation du virus, à prendre des décisions qui auront des incidences sur nous ...

  13. La Fondation Azrieli | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Carrières · Communiquez avec nous · Plan du site. Abonnez-vous à notre bulletin pour recevoir les nouvelles du CRDI chaque mois. Abonnez-vous · Droits d'auteur · Éthique de la recherche · Politique de libre accès · Politique de confidentialité · Transparence · Utilisation du site Web. Suivez-nous; Facebook · Twitter ...

  14. tanzania : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le présent projet porte sur la création d'emplois pour les jeunes et les femmes en Afrique, en mettant l'accent sur les petites et moyennes entreprises (PME) du secteur du tourisme. Région: Mauritius, Tanzania, Uganda. Programme: Employment and Growth. Financement total : CA$ 646,600.00. Renforcer les capacités de ...

  15. Publications | Page 45 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le projet initié par l''ONG Initiatives pour un Développement durable (IDID) " Renforcement des connaissances économiques et de la capacité d''adaptation face aux changements climatiques au Bénin " (PRECAB) vise à améliorer la capacité d''adaptation et la résilience des communautés locales afin.

  16. Publications | Page 46 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le projet initié par l''ONG Initiatives pour un Développement durable (IDID) " Renforcement des connaissances économiques et de la capacité d''adaptation face aux changements climatiques au Bénin " (PRECAB) vise à améliorer la capacité d''adaptation et la résilience des communautés locales afin.

  17. Inde | Page 107 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    S'il se peut bien que les changements climatiques viennent aggraver le problème, il ressort de recherches menées dans deux bassins versants du sud du pays que la pollution industrielle, l'exploitation non réglementée des ressources et les changements d'utilisation des terres sont les principales menaces pour la qualité ...

  18. Publications | Page 39 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Pour des villes d'Amérique centrale plus sécuritaires : Réaction de la communauté au crime et à la violence. Pourquoi les villes où il existe des conditions d'exclusion sociale similaires présentent-elles des degrés de violence différents? Des chercheurs du Costa Rica et du Salvador, soutenus par le CRDI, communiquent ...

  19. Inde | Page 116 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le Programme d'action de Beijing visait à rendre toutes les femmes autonomes. Mais avons-nous perdu quelque chose dans les batailles considérées comme remportées ? Et qu'avons-nous gagné dans les batailles considérées comme perdues ? Read more about Supprimer les obstacles pour renforcer l'autonomie des ...

  20. Inde | Page 22 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'une des premières évaluations officielles d'un programme de services de garde d'enfants pour les ménages à faible revenu en Inde pourrait fournir des données empiriques permettant d'améliorer l'égalité des sexes au pays et au-delà de ses frontières. Read more about Le pouvoir des services de garde d'enfants.

  1. Publications | Page 213 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Projet de recherche : gouvernance et qualité des soins au Bénin; rapport final de recherche (restricted access). Dans le cadre de l''objectif social de l''OMS " Santé pour tous ", les pays africains comme le Bénin ont entrepris des reformes de leur système de santé avec la décentralisation des structures de soins et la mise en ...

  2. Publications | Page 111 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Technologie et langue : apprendre à dire souris en kiché. Quand, dès l'âge de la maternelle, des enfants s'assoient pour la première fois devant un ordinateur équipé d'un logiciel en kiché, leur langue maternelle maya, les leçons dépassent de loin la maîtrise de connaissances élémentaires en.

  3. Publications | Page 5 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... produits et de services financiers à l'intention des jeunes. Revitalizing Health for All : Case Studies of the Struggle for Comprehensive Primary Health Care. Le concept de soins de santé primaires complets (SSPC) est axé sur les efforts déployés par le système de santé pour améliorer l'égalité d'accès aux soins de santé, ...

  4. Livres | Page 21 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ISBN: 190239142X. Le débat des semences volume 2 : Solutions pour les lois nationales régissant le contrôle des ressources génétiques et des innovations biologiques. Le Débat des semences met les lecteurs au courant de ce qui a changé — sur le plan scientifique, politique et environnemental — depuis la publication ...

  5. Publications | Page 20 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Cependant, il est couramment utilisé comme combustible, dans les régions rurales, pour faire cuire le pain dans un four traditionnel. Des chercheurs insistent sur l'importance de favoriser la résilience aux changements climatiques des producteurs de maïs d'Afrique du Sud. Des recherches ont démontré que le rendement ...

  6. Foire aux questions pour la bourse de recherche

    International Development Research Centre (IDRC) Digital Library (Canada)

    Jean-Claude Dumais

    Suis-je admissible à une bourse de recherche ? 3. Quelle est la date butoir pour présenter une demande dans le cadre de ce concours ? 4. Quelle est la durée de la période visée par la bourse ? 5. Je suis tenu d'effectuer un stage de deux mois dans le cadre de mes études. Suis-je admissible à une bourse de recherche ?

  7. AUCC - Partenariat 2009-2011 | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Comme on peut le lire dans la Déclaration de l'AUCC sur l'internationalisation et les universités canadiennes : " Nos universités ont une longue tradition de ... et délibérée de notre manière d'enseigner et d'apprendre, essentielle pour assurer la qualité future de l'enseignement supérieur et même l'avenir du Canada.

  8. Bourses doctorales pour renforcer le leadership en Afrique ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Bourses doctorales pour renforcer le leadership en Afrique subsaharienne dans la recherche sur la prévention du VIH. L'Afrique demeure la région la plus durement touchée par l'épidémie de sida, et la prévention du VIH/sida demeure une priorité mondiale en matière de santé. Ce projet appuie l'émergence de ...

  9. Un programme de conservation pour l'ibis chauve (Geronticus ...

    African Journals Online (AJOL)

    (SEO), a permis d'obtenir des résultats au niveau de la productivité et de la connaissance de l'écologie de l'espèce. La taille de la population a connu une augmentation grâce aux efforts entrepris pour assurer le succès de la reproduction. Le régime alimentaire ainsi que les sites d'alimentation convenables sont identifiés ...

  10. Publications | Page 4 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Une application pour téléphone intelligent améliore l'élevage durable du bétail en Éthiopie. L'Éthiopie compte l'une des populations d'animaux d'élevage les plus élevées de l'Afrique. Le bétail représente l'un des segments des plus importants de cette population, comptant environ 50 millions d'animaux.

  11. Publications | Page 42 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La pisciculture pour améliorer les moyens de subsistance en Bolivie. ​Source importante de protéines, d'oligo-éléments et d'acides gras, le poisson peut permettre d'améliorer grandement la sécurité alimentaire et les moyens de subsistance en milieu rural. Pays sans accès maritime, la Bolivie possède l'un des taux de ...

  12. Poursuivre les travaux en cours pour la lutte antitabac | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    29 mai 2017 ... Pour compiler des statistiques comparatives sur les politiques fiscales et la consommation de tabac, un effort important de réseautage s'est avéré nécessaire à travers les bureaucraties des ministères de la santé et des finances dans 15 pays. Ces données ont permis une transformation radicale, y compris ...

  13. Monte Solberg | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Carrières · Communiquez avec nous · Plan du site. Abonnez-vous à notre bulletin pour recevoir les nouvelles du CRDI chaque mois. Abonnez-vous · Droits d'auteur · Éthique de la recherche · Politique de libre accès · Politique de confidentialité · Transparence · Utilisation du site Web. Suivez-nous; Facebook · Twitter ...

  14. Des solutions pratiques pour l'agriculture africaine | CRDI - Centre ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    25 nov. 2016 ... Solar tent fish drier. Au Kenya et en Ouganda, des milliers de cultivateurs font pousser des variétés de haricots sélectionnées pour leur aptitude à être précuites et permettant un meilleur rendement que les variétés locales : 13 650 agriculteurs (6 442 hommes et 7 208 femmes) produisent des nouvelles ...

  15. Myanmar : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Una Hakika : Porter à grande échelle les solutions numériques pour la gestion des conflits au Kenya et en Birmanie. Projet. L'information erronée, qu'elle soit le fruit de rumeurs ou d'une désinformation intentionnelle, peut alimenter le conflit et exercer de profondes répercussions sur la paix, la sécurité et la gouvernance ...

  16. Consolider les preuves scientifiques pour faciliter l'orientation des ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Carrières · Communiquez avec nous · Plan du site. Abonnez-vous à notre bulletin pour recevoir les nouvelles du CRDI chaque mois. Abonnez-vous · Droits d'auteur · Éthique de la recherche · Politique de libre accès · Politique de confidentialité · Transparence · Utilisation du site Web. Suivez-nous; Facebook · Twitter ...

  17. mexico : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Financement total : CA$ 1,492,100.00. Exploiter les données massives pour atteindre les objectifs de développement durable - Créer des compétences dans l'hémisphère sud. Projet ... Financement total : CA$ 79,500.00. Phase II de Prospera Digital : Inclusion financière des femmes à faible revenu au Mexique. Projet.

  18. Publications | Page 94 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le CRDI collabore avec les chercheurs et les établissements des pays en développement au renforcement des capacités locales par le truchement du financement, ... Le syndrome... Diamants de guerre — pour en finir. L'important accord international sur les diamants conclu cette année ne portera pas fruits s'il n'est pas ...

  19. Getting connected in Myanmar | CRDI - Centre de recherches pour ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    23 sept. 2016 ... Les technologies de l'information et de la communication : un moyen d'améliorer la santé des populations en Asie du Sud. Aux quatre coins de l'Asie, les systèmes de santé peinent à assurer l'accès aux services de santé, surtout pour les populations vulnérables. Voir davantageLes technologies de ...

  20. Livres | Page 23 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le monde entier connaît actuellement un profond changement lié au développement du réseau mondial de l'information et de la communication : internet. ... Dans le cadre des activités préparatoires à la conférence internationale sur la recherche en santé pour le développement qui a eu lieu à Bangkok en octobre 2000, ...

  1. Publications | Page 76 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... techniques de télédétection novatrices permettent de rendre compte de la pauvreté en Angola. Pour mesurer les répercussions de la croissance rapide des bidonvilles sur l'environnement en Angola, un bénéficiaire de subvention de longue date du CRDI conjugue des observations obtenues par satellite et des données.

  2. Supprimer les obstacles pour renforcer l'autonomie des femmes ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    1 févr. 2011 ... Ratna Kapur, directrice du Centre for Feminist Legal Research de New Delhi, a traité ces questions lors d'un débat public qui a eu lieu le 7 mars au siège du Centre de recherches pour le développement international (CRDI) et auquel assistaient quelques 65 personnes représentant des organisations non ...

  3. Publications | Page 214 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Forêts communautaires dans le Bassin Arachidier : quelles stratégies locales pour une gestion réussie?; mémoire de fin d'études (restricted access). Les forêts communautaires (jachères, bas-fonds et ressources pastorales) jouent un rôle important dans la vie des populations rurales. Elles sont des sources ...

  4. Publications | Page 14 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le livre 2016 Ciudades de Vida y Muerte: La ville et le pacte social pour la contention de la violence présente une analyse convaincante de la coexistence de la violence et de la corruption Avec compassion et solidarité dans les villes du Venezuela - et les leçons qui peuvent être tirées de leur expérience. Cities of Life and ...

  5. Kenya | Page 47 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    En août 2013, iHub Research a publié les résultats d'une étude subventionnée par le CRDI qui a porté sur la mise au point d'un cadre d'impartition à grande échelle (collecte d'information auprès des citoyens au moyen de plateformes en ligne telles que Twitter, Facebook et les messageries texte) pour suivre une ...

  6. Kathryn Touré | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Carrières · Communiquez avec nous · Plan du site. Abonnez-vous à notre bulletin pour recevoir les nouvelles du CRDI chaque mois. Abonnez-vous · Droits d'auteur · Éthique de la recherche · Politique de libre accès · Politique de confidentialité · Transparence · Utilisation du site Web. Suivez-nous; Facebook · Twitter ...

  7. bolivia : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Dans le cadre de ce projet, on étudiera les efforts déployés par le secteur privé pour améliorer la conformité aux lois contre la corruption en Amérique latine. Sujet: CORRUPTION. Région: Argentina, Bolivia, Brazil, Chile, Colombia, Paraguay, Peru. Programme: Gouvernance et justice. Financement total : CA$ 622,300.00.

  8. Anindya Chatterjee | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Après avoir reçu son diplôme de médecine du Kolkata Medical College and Hospital en 1983, il a poursuivi ses études à l'University College of Medicine, en Inde, pour obtenir un doctorat en psychiatrie et a suivi une formation postdoctorale en anthropologie et en santé publique à la fois à l'University of Calcutta et à la ...

  9. Désabonnez-vous | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Abonnez-vous à notre bulletin pour recevoir les nouvelles du CRDI chaque mois. Abonnez-vous · Droits d'auteur · Éthique de la recherche · Politique de libre accès · Politique de confidentialité · Transparence · Utilisation du site Web. Suivez-nous; Facebook · Twitter · Youtube · Linked In · RSS Feed. © 2015 CRDI.

  10. Le Conseil des gouverneurs | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le Conseil des gouverneurs guide le travail du CRDI en lui fournissant une orientation stratégique, en examinant ses activités et en approuvant ses budgets. Les gouverneurs – un maximum de 14 – sont nommés par le gouverneur en conseil du Canada pour un mandat d'au plus quatre ans, qui peut être reconduit. La Loi ...

  11. Dominique Charron | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    À titre de directrice du domaine de programme Agriculture et environnement, Dominique Charron veille au bon déroulement d'activités de recherche ayant pour but d'accroître la productivité de l'agriculture et la sécurité alimentaire et hydrique tout en veillant à assurer la pérennité de l'environnement. Elle dirige également ...

  12. Abonnez-vous | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Abonnez-vous à notre bulletin pour recevoir les nouvelles du CRDI chaque mois. Abonnez-vous · Droits d'auteur · Éthique de la recherche · Politique de libre accès · Politique de confidentialité · Transparence · Utilisation du site Web. Suivez-nous; Facebook · Twitter · Youtube · Linked In · RSS Feed. © 2015 CRDI.

  13. Publications | Page 189 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Les changements climatiques brouillent les prédictions des faiseurs de pluie. Depuis des générations, les autochtones de l'ouest du Kenya comptent sur les pouvoirs mystiques que possèdent les « faiseurs de pluie » du clan Nganyi pour prédire la météo. Cependant, le temps instable amené par les changements ...

  14. Véronique Duvieusart | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Carrières · Communiquez avec nous · Plan du site. Abonnez-vous à notre bulletin pour recevoir les nouvelles du CRDI chaque mois. Abonnez-vous · Droits d'auteur · Éthique de la recherche · Politique de libre accès · Politique de confidentialité · Transparence · Utilisation du site Web. Suivez-nous; Facebook · Twitter ...

  15. Building Bridges : Tisser des liens pour mettre en rapport les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    1 mai 2017 ... Le programme Building Bridges offre aux dirigeants africains un espace sûr pour mener un dialogue constructif, systématique et durable sur des ... liens afin de combler les écarts entre les analyses et les réflexions des acteurs politiques, des décideurs et des spécialistes de la recherche sur les politiques.

  16. Publications | Page 126 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    122 · 123 · 124 · 125; 126; 127 · 128 · 129 · 130 … suivant › · dernier » · Ce que nous faisons · Financement · Ressources · À propos du CRDI. Savoir. Innovation. Solutions. Carrières · Communiquez avec nous · Plan du site. Abonnez-vous à notre bulletin pour recevoir les nouvelles du CRDI chaque mois. Abonnez-vous.

  17. Le futur du travail | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    12 juin 2017 ... Une base de données probantes est nécessaire afin de trouver des solutions stratégiques et sociales appropriées aux divers défis que posent ces nouveaux modes de travail. La recherche sur l'innovation en matière d'éducation et le renforcement des capacités seront également essentiels pour assurer la ...

  18. Gestion du Centre | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le Comité de gestion du Centre (CGC) est composé des membres de la haute direction du CRDI, notamment les directeurs de nos quatre bureaux régionaux et de nos principaux secteurs de programme. Le CGC travaille en collaboration avec le président afin de soutenir la recherche pour le développement, lui fournissant ...

  19. Gravity and On-Shell Probe Actions

    CERN Document Server

    Ferrari, Frank

    2016-08-08

    In any gravitational theory and in a wide class of background space-times, we argue that there exists a simple, yet profound, relation between the on-shell Euclidean gravitational action and the on-shell Euclidean action of probes. The probes can be, for instance, charged particles or branes. The relation is tightly related to the thermodynamic nature of gravity. We provide precise checks of the relation in several examples, which include both asymptotically flat and asymptotically AdS space-times, with particle, D-brane and M-brane probes. Perfect consistency is found in all cases, including in a highly non-trivial example including \\alpha'-corrections.

  20. Practical applications of substructuring in shell dynamics

    International Nuclear Information System (INIS)

    Sane, A.D.; Bitner, J.L.

    1982-01-01

    Transient dynamic stress analysis of large shell structures is often required in many industrial designs. The asymmetry features of the structure often require a full three dimensional analysis. The difficulties experienced in performing the dynamic analysis of such large and complex structures result from economic feasibility and limitations on the available computer core memory. Substructuring techniques provide a way of overcoming these difficulties. The advantages and features associated with substructuring methods are discussed in general terms. The technique is then applied to perform a transient dynamic analysis of a typical shell structure. The discussion of the example problem focused to highlight the economy, flexibility and the data handling aspects of this method. The example problem demonstrates that this method can be applied with success to a wide range of structural dynamic problems and results in significant cost savings

  1. Shell model calculations for exotic nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Brown, B.A. (Michigan State Univ., East Lansing, MI (USA)); Warburton, E.K. (Brookhaven National Lab., Upton, NY (USA)); Wildenthal, B.H. (New Mexico Univ., Albuquerque, NM (USA). Dept. of Physics and Astronomy)

    1990-02-01

    In this paper we review the progress of the shell-model approach to understanding the properties of light exotic nuclei (A < 40). By shell-model'' we mean the consistent and large-scale application of the classic methods discussed, for example, in the book of de-Shalit and Talmi. Modern calculations incorporate as many of the important configurations as possible and make use of realistic effective interactions for the valence nucleons. Properties such as the nuclear densities depend on the mean-field potential, which is usually separately from the valence interaction. We will discuss results for radii which are based on a standard Hartree-Fock approach with Skyrme-type interactions.

  2. BLAZAR FLARES FROM COMPTON DRAGGED SHELLS

    Energy Technology Data Exchange (ETDEWEB)

    Golan, Omri; Levinson, Amir, E-mail: Levinson@wise.tau.ac.il [School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978 (Israel)

    2015-08-10

    We compute the dynamics and emission of dissipative shells that are subject to a strong Compton drag, under simplifying assumptions about the dissipation mechanism. We show that under conditions prevailing in blazars, substantial deceleration is anticipated on sub-parsec and parsec scales in cases of rapid dissipation. Such episodes may be the origin of some of the flaring activity occasionally observed in gamma-ray blazars. The shape of the light curves thereby produced reflects the geometry of the emitting surface if the deceleration is very rapid, or the dynamics of the shell if the deceleration is delayed, or initially more gradual, owing, e.g., to continuous injection of energy and momentum.

  3. Robust, ultrasmall organosilica nanoparticles without silica shells

    Science.gov (United States)

    Murray, Eoin; Born, Philip; Weber, Anika; Kraus, Tobias

    2014-07-01

    Traditionally, organosilica nanoparticles have been prepared inside micelles with an external silica shell for mechanical support. Here, we compare these hybrid core-shell particles with organosilica particles that are robust enough to be produced both inside micelles and alone in a sol-gel process. These particles form from octadecyltrimethoxy silane as silica source either in microemulsions, resulting in water-dispersible particles with a hydrophobic core, or precipitate from an aqueous mixture to form particles with both hydrophobic core and surface. We examine size and morphology of the particles by dynamic light scattering and transmission electron microscopy and show that the particles consist of Si-O-Si networks pervaded by alkyl chains using nuclear magnetic resonance, infrared spectroscopy, and thermogravimetric analysis.

  4. Logistique ST-HM pour le projet LHC

    CERN Document Server

    Prodon, S

    2002-01-01

    Ce papier a pour objectif de présenter la structure mise en place au sein du groupe ST-HM pour assurer la logistique d'installation du projet LHC. L'aspect traèabilité sera tout d'abord évoqué avec notamment la mise en place d'outils informatiques tels que le formulaire EDH de demande d'intervention transport-manutention et le système SIRIAC de suivi et de validation des transports réalisés. Ces développements informatiques s'intègrent dans le cadre plus général des modalités de traèabilité des équipements établies en collaboration avec le groupe SL/MR, chargé de la gestion des espaces pour le projet LHC. Les procédures proprement dites de transport des équipements feront l'objet d'un développement particulier. Leur processus d'élaboration sera détaillé : des premières réunions d'information jusqu'à la validation finale par les trois parties (demandeur, groupe ST-HM et contractant ST-HM). L'intégration de ces documents dans la logistique générale ST-HM de planification des ressou...

  5. Influence of delayed pouring on irreversible hydrocolloid properties

    Directory of Open Access Journals (Sweden)

    Stéfani Becker Rodrigues

    2012-10-01

    Full Text Available The aim of this study was to evaluate the physical properties of irreversible hydrocolloid materials poured immediately and after different storage periods. Four alginates were tested: Color Change (Cavex; Hydrogum (Zhermack; Hydrogum 5 (Zhermack; and Hydro Print Premium (Coltene. Their physical properties, including the recovery from deformation (n = 3, compressive strength (n = 3, and detail reproduction and gypsum compatibility (n = 3, were analyzed according to ANSI/ADA specification no. 18. Specimens were stored at 23ºC and humidity and were then poured with gypsum immediately and after 1, 2, 3, 4, and 5 days. The data were analyzed by two-way analysis of variance (ANOVA and Tukey's test at p < 0.05. All of the alginate impression materials tested exhibited detail reproduction and gypsum compatibility at all times. Hydro Print Premium and Hydrogum 5 showed recovery from deformation, as established by ANSI/ADA specification no. 18, after 5 days of storage. As the storage time increased, the compressive strength values also increased. Considering the properties of compounds' recovery from deformation, compressive strength, and detail reproduction and gypsum compatibility, irreversible hydrocolloids should be poured immediately.

  6. Big Bang pour le grand public - French version only

    CERN Multimedia

    2004-01-01

    Pour commémorer les 50 ans du CERN et l'année de la physique en 2005, la section de physique de l'Université de Genève ouvre une fois de plus ses portes aux non initiés et organise une série de conférences de vulgarisation scientifique. La première conférence, le 7 décembre prochain aura pour thème le Big-Bang et les observations qui corroborent cette théorie. Le Professeur Georges Meylan, Directeur du Laboratoire d'Astrophysique de l'EPFL, donnera cette conférence destinée à tous les publics. Chacune des conférences débutera par une démonstration de détection de rayons cosmiques dans l'auditoire et l'utilisation de ces signaux venus du fond de l'univers pour créer une ?musique cosmique', en collaboration avec le Professeur Ellberger et Nikolai Mihailov du conservatoire de musique de Genève. Ces processus cosmiques étant aléatoires, chacun de ces concerts sera unique. Les preuves observationnelles du Big Bang par le Professeur Georges Meylan Directeur du Laboratoire d'Astrophysique ...

  7. Pour une recherche technologique en sciences humaines et sociales

    Directory of Open Access Journals (Sweden)

    Lenay Charles

    2014-01-01

    Full Text Available Nous proposons ici une approche originale de la technologie dans les sciences humaines et sociale (SHS, approche qui sera développée dans le cadre d'un groupement d'intérêt scientifique (GIS pour l'unité des technologies et des sciences de l'homme. En effet, la place des SHS dans l'organisation de la recherche et des enseignements dispensés dans les écoles d'ingénieurs pose question. Les attentes vis-à-vis des enseignants-chercheurs sont souvent l'objet de malentendus et renvoient pour partie à une méconnaissance réciproque entre SHS et sciences pour l'ingénieur (SPI mais aussi, plus fondamentalement à une coupure entre enseignement et recherche. Ces obstacles illustrent également la difficulté à mettre en place une recherche interdisciplinaire pérenne qui associe SHS et SPI. Nous proposons ici une initiative qui vise à fonder une recherche interdisciplinaire de ce type sur la question de la « constitutivité mutuelle » de l'Homme et de la technique.

  8. On Newton’s shell theorem

    International Nuclear Information System (INIS)

    Borghi, Riccardo

    2014-01-01

    In the present letter, Newton’s theorem for the gravitational field outside a uniform spherical shell is considered. In particular, a purely geometric proof of proposition LXXI/theorem XXXI of Newton’s Principia, which is suitable for undergraduates and even skilled high-school students, is proposed. Minimal knowledge of elementary calculus and three-dimensional Euclidean geometry are required. (letters and comments)

  9. Shell Canada Limited 1998 annual report

    International Nuclear Information System (INIS)

    1999-01-01

    A report of operational and financial achievements is reported. Shell Canada's Resources Division is one of Canada's largest producers of crude oil, natural gas, natural gas liquids, sulphur and bitumen. This report presents an operations review, provides consolidated financial statements, and common share information, and summarizes revenue and expenditure statements. The company was one of Canada's most profitable integrated oil and gas companies in 1998. It was the second most profitable year in the company's history for continuing operations. Oil products earnings for 1998 were a record $275 million, mostly because of strong sales volumes and increased retail market share. The company also confronted several environmental issues in 1998, including climate change and the reduction of greenhouse gases. Construction of the Sable Project, offshore Nova Scotia, continued on budget and on schedule to bring natural gas to market by early 2000. Plans for the three elements of the Oil Sands project (the Muskeg River mine in the Athabaska Region, an upgrader at Shell's Scotford site and the Corridor Pipeline) proceeded on schedule. The Caroline complex made its expected contribution to the company's overall performance. Improved seismic technology helped to add new reserves through Shell's interest in wells in southern Alberta. Exploration activity in northeastern British Columbia and northern Alberta produced encouraging results. The work will continue in 1999. The company plans to invest some 4.9 billion dollars over the next five years in capital expenditures. Shell remains committed to the Voluntary Challenge and Registry Program. Annual reduction of CO 2 emissions increased by an estimated 800,000 tonnes

  10. Shell Measuring Machine. History and Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Birchler, Wilbur D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fresquez, Philip R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2000-06-01

    Commercialization of the Ring Rotacon Shell Measuring Machine project is a CRADA (NO. LA98C10358) between The University of California (Los Alamos National Laboratory) and Moore Tool Company, Bridgeport, CT. The actual work started on this CRADA in December of 1998. Several meetings were held with the interested parties (Los Alamos, Oak Ridge, Moore Tool, and the University of North Carolina). The results of these meetings were that the original Ring Rotacon did not measure up to the requirements of the Department of Energy and private industry, and a new configuration was investigated. This new configuration (Shell Measuring Machine [SMM]) much better fits the needs of all parties. The work accomplished on the Shell Measuring Machine in FY 99 includes the following; Specifications for size and weight were developed; Performance error budgets were established; Designs were developed; Analyses were performed (stiffness and natural frequency); Existing part designs were compared to the working SMM volume; Peer reviews were conducted; Controller requirements were studied; Fixture requirements were evaluated; and Machine motions were analyzed. The consensus of the Peer Review Committee was that the new configuration has the potential to satisfy the shell inspection needs of Department of Energy as well as several commercial customers. They recommended that more analyses be performed on error budgets, structural stiffness, natural frequency, and thermal effects and that operational processes be developed. Several design issues need to be addressed. They are the type of bearings utilized to support the tables (air bearings or mechanical roller type bearings), the selection of the probes, the design of the probe sliding mechanisms, and the design of the upper table positioning mechanism. Each item has several possible solutions, and more work is required to obtain the best design. This report includes the background and technical objectives; minutes of the working

  11. Dynamic nonlinear analysis of shells of revolution

    International Nuclear Information System (INIS)

    Von Riesemann, W.A.; Stricklin, J.A.; Haisler, W.E.

    1975-01-01

    DYNAPLAS is a program for the transient response of ring stiffened shells of revolution subjected to either asymmetric initial velocities or to asymmetric pressure loadings. Both material and geometric nonlinearities may be considered. The present version, DYNAPLAS II, began with the programs SAMMSOR and DYNASOR. As is the case for the earlier programs, a driver program, SAMMSOR III, generates the stiffness and mass matrices for the harmonics under consideration. A highly refined meridionally curved axisymmetric thin shell of revolution element is used in conjunction with beam type ring stiffeners in the circumferential direction. The shell element uses a cubic displacement function and through static condensation a basic eight degree of freedom element is generated. The shell material may be isotropic or orthotropic. DYNAPLAS II uses the 'displacement' method of analysis in which the nonlinearities are treated as pseudo loads on the right-hand side of the equations of motion. The equations are written for each Fourier harmonic used in representing the asymmetric loading components, and although the left-hand side of the equations is uncoupled, the right-hand side is coupled by the nonlinear pseudo loads. The strain displacement equations of Novozhilov are used and the incremental theory of plasticity is used with the von Mises yield condition and associated flow rule. Either isotropic work hardening or the mechanical sublayer model may be used. Strain rate effects may be included. Either the explicit central difference method or the implcit Houbolt method are available. The program has found use in the analysis of containment vessels for light water reactors

  12. Quantum corrected Schwarzschild thin-shell wormhole

    OpenAIRE

    Jusufi, Kimet

    2016-01-01

    Recently, Ali and Khalil (Nucl Phys B, 909, 173–185, 2016 ), based on Bohmian quantum mechanics, derived a quantum corrected version of the Schwarzschild metric. In this paper, we construct a quantum corrected Schwarzschild thin-shell wormhole (QSTSW) and investigate the stability of this wormhole. First we compute the surface stress at the wormhole throat by applying the Darmois–Israel formalism to the modified Schwarzschild metric and show that exotic matter is required at the throat to kee...

  13. Jess, the Java expert system shell

    Energy Technology Data Exchange (ETDEWEB)

    Friedman-Hill, E.J.

    1997-11-01

    This report describes Jess, a clone of the popular CLIPS expert system shell written entirely in Java. Jess supports the development of rule-based expert systems which can be tightly coupled to code written in the powerful, portable Java language. The syntax of the Jess language is discussed, and a comprehensive list of supported functions is presented. A guide to extending Jess by writing Java code is also included.

  14. Muonic atoms with vacant electron shells

    International Nuclear Information System (INIS)

    Bacher, R.; Gotta, D.; Simons, L.M.; Missimer, J.; Mukhopadhyay, N.C.

    1985-01-01

    We show that the cascade in muonic atoms with Z<20 ejects sufficient atomic electrons to ionize an isolated muonic atom completely. In gases, the rates with which electrons refill the atomic shell can be accurately deduced from measured and calculated electron transfer cross sections. Thus, we can conclude that completely ionized muonic atoms can be prepared in gases, and that they remain isolated for long enough times at attainable pressures to facilitate studies of fundamental interactions in muonic atoms

  15. An Experimental Study on Effect of Palm – Shell Waste Additive to Cement Strenght Enhancement

    Directory of Open Access Journals (Sweden)

    Adi Novriansyah

    2017-03-01

    Full Text Available Enhancing the cement strength through attaching chemical additive has been popular to meet the required condition for a particular well-cementing job. However, due to a low oil-price phenomenon, pouring and additive should be reconsidered because it can raise the cost and make the project become uneconomic. Another additive material in nanocomposite form will be introduced through this experimental study. The nanocomposite material consist of silica nanoparticle, known as “Nanosilica” and a palm-shell-waste, which is abundant in Indonesia. Before making a nanocomposite, the palm-shell should be burned to obtain a charcoal form, ground and sieved to attain a uniform size.   The study focuses on the two parameters, compressive strength and shear bond strength, which can reflect the strength of the cement. These values are obtained by performing a biaxial loading test to the cement sample. Various samples with different concentration of nanocomposite should be prepared and following the mixing, drying, and hardening process before the loading test is carried out. The result from the test shows a positive indication for compressive strength and shear bond strength values, according to the representative well cementing standards. Increasing the nanocomposite concentration on the cement will increase these values. Furthermore, an investigation on the temperature effect confirms that the sample with 700oC burning temperature have highest compressive-strength and shear-bond-strength values. This is a potential opportunity utilizing a waste-based material to produce another product with higher economic value.

  16. Radar attenuation in Europa's ice shell: obstacles and opportunities for constraining shell thickness and thermal structure

    Science.gov (United States)

    Kalousova, Klara; Schroeder, Dustin M.; Soderlund, Krista M.; Sotin, Christophe

    2016-10-01

    With its strikingly young surface and possibly recent endogenic activity, Europa is one of the most exciting bodies within our Solar System and a primary target for spacecraft exploration. Future missions to Europa are expected to carry ice penetrating radar instruments which are powerful tools to investigate the subsurface thermophysical structure of its ice shell.Several authors have addressed the 'penetration depth' of radar sounders at icy moons, however, the concept and calculation of a single value penetration depth is a potentially misleading simplification since it ignores the thermal and attenuation structure complexity of a realistic ice shell. Here we move beyond the concept of a single penetration depth by exploring the variation in two-way radar attenuation for a variety of potential thermal structures of Europa's ice shell as well as for a low loss and high loss temperature-dependent attenuation model. The possibility to detect brines is also investigated.Our results indicate that: (i) for all ice shell thicknesses investigated (5-30 km), a nominal satellite-borne radar sounder will penetrate between 15% and 100% of the total thickness, (ii) the maximum penetration depth strongly varies laterally with the deepest penetration possible through the cold downwellings, (iii) the direct detection of the ice/ocean interface might be possible for shells of up to 15 km if the radar signal travels through the cold downwelling, (iv) even if the ice/ocean interface is not detected, the penetration through most of the shell could constrain the deep shell structure through the loss of signal, and (v) for all plausible ice shells the two-way attenuation to the eutectic point is ≤30 dB which shows a robust potential for longitudinal investigation of the ice shell's shallow structure.Part of this work has been performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA. K.K. acknowledges support by the Grant Agency of the

  17. Tubin, Eduard. Sonate pour violon et piano dans le mode phrygien / Pierre Gervasoni

    Index Scriptorium Estoniae

    Gervasoni, Pierre

    1995-01-01

    Uuest heliplaadist "Tubin, Eduard. Sonate pour violon et piano dans le mode phrygien. Ballade pour piano en forme de Chaconne sur un theme de Mart Saar. Sonate pour saxophone alto et piano. Le Chant des soldats enrepli. Ave Maria. Societe Chorale Estudiantine de Lund, Neeme Järvi. BIS-CD 269, distribution Harmonia Mundi (CD: 161 F), 1984/85.TT: 1h 03'46"

  18. Une plateforme pour la mise au point d'un vaccin anti-adénovirus ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Une plateforme pour la mise au point d'un vaccin anti-adénovirus non réplicatif contre les maladies aviaires. 09 avril 2018. Fonds d'innovation en vaccins pour le bétail. Photo: Sven Torfinn/Panos Pictures. La volaille constitue un élevage essentiel en Afrique subsaharienne, surtout pour la sécurité alimentaire et ...

  19. Sexospécificités | Page 183 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Au moment où l'incarnation même de la lutte contre l'apartheid se bat pour sa vie dans un hôpital de Pretoria, l'ancien président du Centre de recherches pour le développement international (CRDI), organisme canadien, livre ses réflexions sur le partenariat établi par le Centre pour appuyer la démocratie en Afrique du ...

  20. Carrières | CRDI - Centre de recherches pour le développement ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le CRDI regroupe des gens qui partagent une passion pour la recherche pour le développement international. La recherche pour le développement contribue réellement à changer les choses lorsqu'elle reçoit un soutien adéquat et que les bonnes personnes y travaillent. Nous recherchons des personnes qui ont la ferme ...

  1. Le débat des semences volume 1 : Solutions politiques pour les ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le débat des semences volume 1 : Solutions politiques pour les ressources génétiques (Un Brevet pour la vie revisité). Couverture du livre Le débat des semences volume 1 : Solutions politiques pour les ressources génétiques. Auteur(s):. Groupe Crucible II. Maison(s) d'édition: IPGRI, DHF, CRDI. 1 janvier 2001. ISBN :.

  2. Avantages possibles de la téléphonie mobile pour la surveillance ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Avantages possibles de la téléphonie mobile pour la surveillance épidémiologique au Mali. La charge de morbidité au Mali est l'une des plus lourdes au monde. L'utilisation de téléphones mobiles pour surveiller les flambées de maladies pourrait contribuer à réduire cette charge. La surveillance de la santé publique pour ...

  3. Gas distribution and starbursts in shell galaxies

    Science.gov (United States)

    Weil, Melinda L.; Hernquist, Lars

    1993-01-01

    Detailed maps of most elliptical galaxies reveal that, whereas the greatest part of their luminous mass originates from a smooth distribution with a surface brightness approximated by a de Vaucouleurs law, a small percentage of their light is contributed by low surface brightness distortions termed 'fine structures'. The sharp-edged features called 'shells' are successfully reproduced by merger and infall models involving accretion from less massive companions. In this context, dwarf spheroidal and compact disk galaxies are likely progenitors of these stellar phenomena. However, it is probable that the sources of shell-forming material also contain significant amounts of gas. This component may play an important role in constraining the formation and evolution of shell galaxies. To investigate the effects of the gaseous component, numerical simulations were performed to study the tidal disruption of dwarf galaxies containing both gas and stars by more massive primaries, and the evolution of the ensuing debris. The calculations were performed with a hybrid N-body/hydrodynamics code. Collisionless matter is evolved using a conventional N-body technique and gas is treated using smoothed particle hydrodynamics in which self-gravitating fluid elements are represented as particles evolving according to Lagrangian hydrodynamic equations. An isothermal equation of state is employed so the gas remains at a temperature 104 K. Owing to the large mass ratio between the primary and companion, the primary is modeled as a rigid potential and the self-gravity of both galaxies is neglected.

  4. Curvature-Induced Instabilities of Shells

    Science.gov (United States)

    Pezzulla, Matteo; Stoop, Norbert; Steranka, Mark P.; Bade, Abdikhalaq J.; Holmes, Douglas P.

    2018-01-01

    Induced by proteins within the cell membrane or by differential growth, heating, or swelling, spontaneous curvatures can drastically affect the morphology of thin bodies and induce mechanical instabilities. Yet, the interaction of spontaneous curvature and geometric frustration in curved shells remains poorly understood. Via a combination of precision experiments on elastomeric spherical shells, simulations, and theory, we show how a spontaneous curvature induces a rotational symmetry-breaking buckling as well as a snapping instability reminiscent of the Venus fly trap closure mechanism. The instabilities, and their dependence on geometry, are rationalized by reducing the spontaneous curvature to an effective mechanical load. This formulation reveals a combined pressurelike term in the bulk and a torquelike term in the boundary, allowing scaling predictions for the instabilities that are in excellent agreement with experiments and simulations. Moreover, the effective pressure analogy suggests a curvature-induced subcritical buckling in closed shells. We determine the critical buckling curvature via a linear stability analysis that accounts for the combination of residual membrane and bending stresses. The prominent role of geometry in our findings suggests the applicability of the results over a wide range of scales.

  5. Fluorescent nanodiamonds embedded in biocompatible translucent shells.

    Science.gov (United States)

    Rehor, Ivan; Slegerova, Jitka; Kucka, Jan; Proks, Vladimir; Petrakova, Vladimira; Adam, Marie-Pierre; Treussart, François; Turner, Stuart; Bals, Sara; Sacha, Pavel; Ledvina, Miroslav; Wen, Amy M; Steinmetz, Nicole F; Cigler, Petr

    2014-03-26

    High pressure high temperature (HPHT) nanodiamonds (NDs) represent extremely promising materials for construction of fluorescent nanoprobes and nanosensors. However, some properties of bare NDs limit their direct use in these applications: they precipitate in biological solutions, only a limited set of bio-orthogonal conjugation techniques is available and the accessible material is greatly polydisperse in shape. In this work, we encapsulate bright 30-nm fluorescent nanodiamonds (FNDs) in 10-20-nm thick translucent (i.e., not altering FND fluorescence) silica shells, yielding monodisperse near-spherical particles of mean diameter 66 nm. High yield modification of the shells with PEG chains stabilizes the particles in ionic solutions, making them applicable in biological environments. We further modify the opposite ends of PEG chains with fluorescent dyes or vectoring peptide using click chemistry. High conversion of this bio-orthogonal coupling yielded circa 2000 dye or peptide molecules on a single FND. We demonstrate the superior properties of these particles by in vitro interaction with human prostate cancer cells: while bare nanodiamonds strongly aggregate in the buffer and adsorb onto the cell membrane, the shell encapsulated NDs do not adsorb nonspecifically and they penetrate inside the cells. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Production of hydroxyapatite from waste mussel shells

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Mark I; Barakat, Haneen; Patterson, Darrell Alec, E-mail: mark.jones@auckland.ac.nz [Department Chemical and Materials Engineering, University of Auckland, New Zealand Private Bag 92019, Auckland Mail Centre, Auckland, 1142 (New Zealand)

    2011-10-29

    This work describes the formation of Hydroxyaptite, Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2}, from waste mussel shells from the New Zealand aquaculture industry. The raw shells are first calcined to produce lime (CaO) and then reacted in a purpose built reactor to form the Hydroxyapatite (HA) in a low temperature batch process. The calcination was studied in terms of the effects of temperature, heating rate, holding time, nitrogen flow rate and particle size. The crystals formed in the batch reactor were characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and X-Ray Photoelectron Spectroscopy (XPS). Optimised conditions in the calcination stage resulted in powder with around 95% conversion to lime. The as-produced HA showed poor crystallinity and the presence of impurities, although both of these features were improved by a suitable post heat treatment process. The post treated material showed good crystallinity and was comparable to commercially produced material. Preliminary biocompatibility experiments showed that the HA stimulated cell growth and promoted mineralization. The production of HA from mussel shells in a room temperature, ambient pressure process is not only a sustainable use of waste material, but also from an industrial point of view the process has considerable potential for reducing costs associated with both starting materials and energy.

  7. Nuclear shell effects at high temperatures

    International Nuclear Information System (INIS)

    Davidson, N.J.; Miller, H.G.

    1993-01-01

    In discussing the disappearance of nuclear shell effects at high temperatures, it is important to distinguish between the ''smearing out'' of the single-particle spectrum with increasing temperature and the vanishing of shell related structures in many-body quantities such as the excitation energy per nucleon. We propose a semiempirical method to obtain an upper bound on the temperature required to smooth the single-particle spectrum, and point out that shell effects in many-body parameters may persist above this temperature. We find that the temperature required to smear out the single-particle spectrum is approximately 1 MeV for heavy nuclei (A approx-gt 150) and about 3--4 MeV for light nuclei (A approx-lt 50), in reasonable agreement with the estimate of 41/πA 1/3 obtained from calculations with harmonic oscillator potentials. These temperatures correspond to many-body excitation energies of approximately 20 and 60 MeV, respectively

  8. Electron spin resonance dating of shells from the sambaqui (shell mound) Capelinha, Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    Kinoshita, A.; Figuty, L.; Baffa, O.

    2006-01-01

    Capelinha is a fluvial sambaqui (Brazilian Shell Mound) located in the Ribeira Valley in the State of Sao Paulo that is being studied. It is one of the oldest sambaquis located along a river dated so far in this region. The use of ESR to date other shells stimulated our group to apply this method to the Capelinha site. Shells from land snails (Megalobulimus sp.) obtained in two levels of excavations were analyzed; one of them was in contact with a skeleton that was dated by C-14. The archaeological doses obtained were (8.05±0.07) Gy and (9.50±0.03) Gy. Since the last site was previously dated by C-14 (Beta -Analytics, Beta 153988) giving: 8860 +/- 60 years BP (conventional age) and 10180 to 9710 years BP (calibrated age), the archaeological dose found for this shell was used to determine the local rate of (0.93 to 0.98) mGy/year, that aggress with other surveys done in the region. Using this dose rate the age of the second shell was found to be 8.14 to 8.73 ky BP that agrees with the stratigraphy of the site. (author)

  9. La pisciculture en cage est prisée au Népal | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    25 oct. 2010 ... Des chercheurs du Nepal Agricultural Research Council ont constaté que l'eau du réservoir créé par le barrage se prêtait exceptionnellement bien à l'élevage des poissons, en particulier des carpes, dans de grandes cages flottantes. Le milieu est idéal pour les poissons car le plancton y abonde.

  10. Research on cracking mechanism of the thin shell mould in expendable pattern shell casting during pattern removal process

    Directory of Open Access Journals (Sweden)

    Jiang Wenming

    2010-08-01

    Full Text Available Aiming at the cracking phenomenon of the thin shell mould in the expendable pattern shell casting during the pattern removing process, some systemic researches are presented. The influence of the pattern removing method and temperature on the pattern removing were investigated. The shell mould cracking mechanism was analyzed by using thermo-gravimetric analysis (TGA, and combining the temperature field and the volume change of the expanded polystyrene (EPS foam pattern being tested. The results indicated that the shell mould was not easily cracked when the pattern removing process was carried out with the furnace being heated little by little because of the shell slowly shrinking with dehydration and shell strength gradually increasing. The shell mould was soon destroyed when it was set directly into the furnace at above 400 ℃ because of the thin shell mould rapidly shrinking and the foam pattern hindering. However, the shell mould had no cracking when it had been preheated for a long time even if the furnace temperature was above 400 篊 and the shell was put into the furnace directly. Moreover, when the shell mould was directly set into the furnace at lower temperatures, 250 to 300 ℃, the shell would shrink slowly and the foam pattern would stay at the maximum expansion stage temperature of 100 to 110 ℃ for a long time; and the shell mould would experience an expansion force from the foam pattern for a long time. The expansion force is related to the pattern removing temperature, holding time, foam pattern thickness and density. Therefore, the foam pattern with higher density could make the shell crack.

  11. Accès à l'eau pour les agricultrices sahéliennes : enjeux pour une ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    6 mars 2014 ... La recherche a permis de tracer des pistes pour un accès plus équitable des femmes aux ressources économiques en général et à l'eau à usage agricole en particulier. Un comité transnational de plaidoyer a été mis en place afin de favoriser la mise en oeuvre des recommandations de la recherche.

  12. The heterogeneous ice shell thickness of Enceladus

    Science.gov (United States)

    Lucchetti, Alice; Pozzobon, Riccardo; Mazzarini, Francesco; Cremonese, Gabriele; Massironi, Matteo

    2016-10-01

    Saturn's moon Enceladus is the smallest Solar System body that presents an intense geologic activity on its surface. Plumes erupting from Enceladus' South Polar terrain (SPT) provide direct evidence of a reservoir of liquid below the surface. Previous analysis of gravity data determined that the ice shell above the liquid ocean must be 30-40 km thick from the South Pole up to 50° S latitude (Iess et al., 2014), however, understand the global or regional nature of the ocean beneath the ice crust is still challenging. To infer the thickness of the outer ice shell and prove the global extent of the ocean, we used the self-similar clustering method (Bonnet et al., 2001; Bour et al., 2002) to analyze the widespread fractures of the Enceladus's surface. The spatial distribution of fractures has been analyzed in terms of their self-similar clustering and a two-point correlation method was used to measure the fractal dimension of the fractures population (Mazzarini, 2004, 2010). A self-similar clustering of fractures is characterized by a correlation coefficient with a size range defined by a lower and upper cut-off, that represent a mechanical discontinuity and the thickness of the fractured icy crust, thus connected to the liquid reservoir. Hence, this method allowed us to estimate the icy shell thickness values in different regions of Enceladus from SPT up to northern regions.We mapped fractures in ESRI ArcGis environment in different regions of the satellite improving the recently published geological map (Crow-Willard and Pappalardo, 2015). On these regions we have taken into account the fractures, such as wide troughs and narrow troughs, located in well-defined geological units. Firstly, we analyzed the distribution of South Polar Region fracture patterns finding an ice shell thickness of ~ 31 km, in agreement with gravity measurements (Iess et al., 2014). Then, we applied the same approach to other four regions of the satellite inferring an increasing of the ice

  13. Layer-by-Layer Proteomic Analysis of Mytilus galloprovincialis Shell

    Science.gov (United States)

    Wang, Xin-xing; Bao, Lin-fei; Fan, Mei-hua; Li, Xiao-min; Wu, Chang-wen; Xia, Shu-wei

    2015-01-01

    Bivalve shell is a biomineralized tissue with various layers/microstructures and excellent mechanical properties. Shell matrix proteins (SMPs) pervade and envelop the mineral crystals and play essential roles in biomineralization. Despite that Mytilus is an economically important bivalve, only few proteomic studies have been performed for the shell, and current knowledge of the SMP set responsible for different shell layers of Mytilus remains largely patchy. In this study, we observed that Mytilus galloprovincialis shell contained three layers, including nacre, fibrous prism, and myostracum that is involved in shell-muscle attachment. A parallel proteomic analysis was performed for these three layers. By combining LC-MS/MS analysis with Mytilus EST database interrogations, a whole set of 113 proteins was identified, and the distribution of these proteins in different shell layers followed a mosaic pattern. For each layer, about a half of identified proteins are unique and the others are shared by two or all of three layers. This is the first description of the protein set exclusive to nacre, myostracum, and fibrous prism in Mytilus shell. Moreover, most of identified proteins in the present study are novel SMPs, which greatly extended biomineralization-related protein data of Mytilus. These results are useful, on one hand, for understanding the roles of SMPs in the deposition of different shell layers. On the other hand, the identified protein set of myostracum provides candidates for further exploring the mechanism of adductor muscle-shell attachment. PMID:26218932

  14. (Plasmonic Metal Core)/(Semiconductor Shell) Nanostructures

    Science.gov (United States)

    Fang, Caihong

    Over the past several years, integration of metal nanocrystals that can support localized surface plasmon has been demonstrated as one of the most promising methods to the improvement of the light-harvesting efficiency of semiconductors. Ag and Au nanocrystals have been extensively hybridized with semiconductors by either deposition or anchoring. However, metal nanocrystals tend to aggregate, reshape, detach, or grow into large nanocrystals, leading to a loss of the unique properties seen in the original nanocrystals. Fortunately, core/shell nanostructures, circumventing the aforementioned problems, have been demonstrated to exhibit superior photoactivities. To further improve the light-harvesting applications of (plasmonic metal core)/(semiconductor shell) nanostructures, it is vital to understand the plasmonic and structural evolutions during the preparation processes, design novel hybrid nanostructures, and improve their light-harvesting performances. In this thesis, I therefore studied the plasmonic and structural evolutions during the formation of (Ag core)/(Ag2S shell) nanostructures. Moreover, I also prepared (noble metal core)/(TiO2 shell) nanostructures and investigated their plasmonic properties and photon-harvesting applications. Clear understanding of the sulfidation process can enable fine control of the plasmonic properties as well as the structural composition of Ag/Ag 2S nanomaterials. Therefore, I investigated the plasmonic and structural variations during the sulfidation process of Ag nanocubes both experimentally and numerically. The sulfidation reactions were carried out at both the ensemble and single-particle levels. Electrodynamic simulations were also employed to study the variations of the plasmonic properties and plasmon modes. Both experiment and simulation results revealed that sulfidation initiates at the vertices of Ag nanocubes. Ag nanocubes are then gradually truncated and each nanocube becomes a nanosphere eventually. The cubic

  15. Effects of Shell-Buckling Knockdown Factors in Large Cylindrical Shells

    Science.gov (United States)

    Hrinda, Glenn A.

    2012-01-01

    Shell-buckling knockdown factors (SBKF) have been used in large cylindrical shell structures to account for uncertainty in buckling loads. As the diameter of the cylinder increases, achieving the manufacturing tolerances becomes increasingly more difficult. Knockdown factors account for manufacturing imperfections in the shell geometry by decreasing the allowable buckling load of the cylinder. In this paper, large-diameter (33 ft) cylinders are investigated by using various SBKF's. An investigation that is based on finite-element analysis (FEA) is used to develop design sensitivity relationships. Different manufacturing imperfections are modeled into a perfect cylinder to investigate the effects of these imperfections on buckling. The analysis results may be applicable to large- diameter rockets, cylindrical tower structures, bulk storage tanks, and silos.

  16. Core-shell Au@Pd nanoparticles with enhanced catalytic activity for oxygen reduction reaction via core-shell Au@Ag/Pd constructions

    OpenAIRE

    Chen, Dong; Li, Chengyin; Liu, Hui; Ye, Feng; Yang, Jun

    2015-01-01

    Core-shell nanoparticles often exhibit improved catalytic properties due to the lattice strain created in these core-shell particles. Herein, we demonstrate the synthesis of core-shell Au@Pd nanoparticles from their core-shell Au@Ag/Pd parents. This strategy begins with the preparation of core-shell Au@Ag nanoparticles in an organic solvent. Then, the pure Ag shells are converted into the shells made of Ag/Pd alloy by galvanic replacement reaction between the Ag shells and Pd2+ precursors. Su...

  17. Windows PowerShell Cookbook The Complete Guide to Scripting Microsoft's New Command Shell

    CERN Document Server

    Holmes, Lee

    2010-01-01

    Do you know how to use Windows PowerShell to navigate the filesystem and manage files and folders? Or how to retrieve a web page? This introduction to the PowerShell language and scripting environment provides more than 430 task-oriented recipes to help you solve the most complex and pressing problems, and includes more than 100 tried-and-tested scripts that intermediate to advanced system administrators can copy and use immediately. You'll find hands-on tutorials on fundamentals, common tasks, and administrative jobs that you can apply whether you're on a client or server version of Windows

  18. Effets de la couverture des cages flottantes et de la période de ...

    African Journals Online (AJOL)

    Administrateur

    final (g), Pmi = poids moyen initial, et t = durée de l'élevage en jours,. Cv (%) = 100 x (écart-type / poids moyen). 2.3. Analyses statistiques. Les données de croissance et de survie sont présentées sous forme de moyennes avec leurs écarts types. Le poids moyen final, le coefficient de variation du poids final et le taux de ...

  19. Effets de la couverture des cages flottantes et de la période de ...

    African Journals Online (AJOL)

    aliment n\\'a aucune influence sur la croissance des poissons. The effects of covering the breeding floating cages with a black plastic canvas and the feeding period (day or night) on the survival and growth of the african cat-fish Heterobranchus ...

  20. Shell thickness effects on quantum dot brightness and energy transfer.

    Science.gov (United States)

    Chern, Margaret; Nguyen, Thuy T; Mahler, Andrew H; Dennis, Allison M

    2017-11-02

    Heterostructured core/shell quantum dots (QDs) are prized in biomedical imaging and biosensing applications because of their bright, photostable emission and effectiveness as Förster resonance energy transfer (FRET) donors. However, as nanomaterials chemistry has progressed beyond traditional QDs to incorporate new compositions, ultra-thick shells, and alloyed structures, few of these materials have had their optical properties systematically characterized for effective application. For example, thick-shelled QDs, also known as 'giant' QDs (gQDs) are useful in single-particle tracking microscopy because of their reduced blinking, but we know only that CdSe/CdS gQDs are qualitatively brighter than thin-shelled CdSe/CdS in aqueous media. In this study, we quantify the impact of shell thickness on the nanoparticle molar extinction coefficient, quantum yield, brightness, and effectiveness as a FRET donor for CdSe/xCdS core/shell and CdSe/xCdS/ZnS core/shell/shell QDs, with variable thicknesses of the CdS shell (x). Molar extinction coefficients up to three orders of magnitude higher than conventional dyes and forty-fold greater than traditional QDs are reported. When thick CdS shells are combined with ZnS capping, quantum yields following thiol ligand exchange reach nearly 40%-5-10× higher than either the commercially available QDs or gQDs without ZnS caps treated the same way. These results clearly show that thick CdS shells and ZnS capping shells work in concert to provide the brightest possible CdSe-based QDs for bioimaging applications. We demonstrate that thicker shelled gQDs are over 50-fold brighter than their thin-shelled counterparts because of significant increases in their absorption cross-sections and higher quantum yield in aqueous milieu. Consistent with the point-dipole approximation commonly used for QD-FRET, these data show that thick shells contribute to the donor-acceptor distance, reducing FRET efficiency. Despite the reduction in FRET efficiency