Sample records for solide-liquide application aux

  1. Application of solid-liquid TPPBs to the production of L-phenylacetylcarbinol from benzaldehyde using Candida utilis.

    PubMed

    Khan, Tanya R; Daugulis, Andrew J

    2010-11-01

    The biotransformation of benzaldehyde and glucose to L-phenylacetylcarbinol (PAC) using Candida utilis was demonstrated in a solid-liquid two-phase partitioning bioreactor (TPPB) with the aim of reducing substrate, product, and by-product toxicity via sequestration. Previous work in the field had used octanol as the sequestering phase of liquid-liquid TPPBs but was limited by the toxic effects of octanol on C. utilis. To improve solvent selection in any future studies, the critical log?P of C. utilis was determined in the current study to be 4.8 and can be used to predict biocompatible solvents. Bioavailability tests showed alkanes and alkenes to be non-bioavailable. As polymers are biocompatible and non-bioavailable, a wide range of commercially available polymers was screened and it was demonstrated that polymer softness plays a key role in absorptive capability. The polymer Hytrel G3548L was selected as the second phase to sequester benzaldehyde, PAC, and benzyl alcohol, with partition coefficients of 35, 7.5, and 10, respectively. With a 9% by volume partitioning phase, 13.6?g/L biomass of C. utilis achieved an overall PAC concentration of 11?g/L, a 1.9-fold improvement over the single-phase case. Benzyl alcohol concentration was 4.5?g/L, a 1.6-fold reduction. The volumetric productivity was 0.85?g/L?h, a 1.2-fold improvement over the single-phase system. These results demonstrate a promising starting point for solid-liquid TPPBs for PAC production. PMID:20552670

  2. Une Nouvelle Technique de Recalage d'Images avec des Contraintes aux Bords Libres : Application aux Mammographies

    E-print Network

    Cohen, Laurent

    Mammographies A New Image Registration Technique With Free Boundary Constraints : Application To Mammography F les niveaux de gris pour le recalage des mammographies. Contrairement aux mod`eles habituels, ce´ements finis. Pour finir, nous appliquons cet algo- rithme aux mammographies. Mots Clef Minimisation d

  3. A sessile drop setup for the time-resolved synchrotron study of solid-liquid interactions: Application to intermetallic formation in 55%Al-Zn alloys

    SciTech Connect

    Bernier, N., E-mail: n.bernier@yahoo.fr; De Bruyn, D.; De Craene, M.; Scheers, J.; Claessens, S. [OCAS N.V., ArcelorMittal Global R and D Gent, Pres. J.F. Kennedylaan 3, 9060 Zelzate (Belgium); Vaughan, G. B. M.; Vitoux, H.; Gleyzolle, H.; Gorges, B. [European Synchrotron Radiation Facility, BP 220, 38043 Grenoble Cedex (France)

    2014-04-28

    We introduce a dedicated setup for measuring by synchrotron diffraction in-situ crystallographic and chemical information at the solid–liquid interface. This setup mostly consists of a double-heating furnace composed of a resistive heating for the solid surface and an inductive heating to produce a liquid droplet. The available high energy and high flux beams allow the rapid reaction kinetics to be investigated with very good time resolution down to 1 ms. An application of this setup is illustrated for the growth mechanisms of intermetallic phases during the hot-dipping of steel in a 55%Al-Zn bath. Results show that the three ?-Al{sub 5}Fe{sub 2}, ?-Al{sub 13}Fe{sub 4}, and ?-Al{sub 8}Fe{sub 2}Si phases grow at different times and rates during the dipping process, whereas the face-centered cubic AlFe{sub 3} phase is not formed.

  4. APPLICATION DES PALIERS A GAZ AUX GYROSCOPES Par G. GOBERT,

    E-print Network

    Paris-Sud XI, Université de

    43 APPLICATION DES PALIERS A GAZ AUX GYROSCOPES Par G. GOBERT, Centre d'Études Nucléaires de Saclay gyroscope dont le rotor de 4 cm de diamètre pesant plusieurs centaines de grammes tourne à une vitesse to the construction of a gyroscope. The rotor is 4 cm in diameter and runs at 180 000 r. p. m. Its weight is 500 g. LE

  5. Solid-Liquid Interfacial Premelting

    E-print Network

    Yang, Yang; Asta, Mark; Laird, Brian Bostian

    2013-02-28

    We report the observation of a premelting transition at chemically sharp solid-liquid interfaces using molecular-dynamics simulations. The transition is observed in the solid-Al—liquid-Pb system and involves the formation ...

  6. Quelques proprietes topologiques des graphes et applications `a Internet et aux reseaux

    E-print Network

    Rapaport, Iván

    Quelques propri´et´es topologiques des graphes et applications `a Internet et aux r´eseaux Mauricio Diderot INRIA Paris Rocquencourt 2 d´ecembre 2011 Mauricio Soto Quelques propri´et´es topologiques des graphes et applications `a Internet et aux r´eseaux 1 / 53 #12;Arborescence des graphes Arborescence d

  7. Calculation of multicomponent chemical equilibria in gas-solid- liquid systems: calculation methods, thermochemical data, and applications to studies of high-temperature volcanic gases with examples from Mount St. Helens

    USGS Publications Warehouse

    Symonds, R.B.; Reed, M.H.

    1993-01-01

    This paper documents the numerical formulations, thermochemical data base, and possible applications of computer programs, SOLVGAS and GASWORKS, for calculating multicomponent chemical equilibria in gas-solid-liquid systems. SOLVGAS and GASWORKS compute simultaneous equilibria by solving simultaneously a set of mass balance and mass action equations written for all gas species and for all gas-solid or gas-liquid equilibria. Examples of gas-evaporation-from-magma and precipitation-with-cooling calculations for volcanic gases collected from Mount St. Helens are shown. -from Authors

  8. Systmes de raction-diffusion et HPC: application aux Thierry Dumont1, Violaine Louvet1

    E-print Network

    Louvet, Violaine

    Systèmes de réaction-diffusion et HPC: application aux AVC Thierry Dumont1, Violaine Louvet1. Louvet Systèmes de RD et HPC Séminaire Rouen 1 / 45 #12;1 Contexte et enjeux sociétaux 2 Modélisation de Conclusions et perspectives V. Louvet Systèmes de RD et HPC Séminaire Rouen 2 / 45 #12;Contexte et enjeux

  9. PROBLMES POSS POUR L'APPLICATION DES ALLIAGES DE NIOBIUM AUX AUBES DE TURBINE

    E-print Network

    Boyer, Edmond

    513 PROBLÈMES POSÉS POUR L'APPLICATION DES ALLIAGES DE NIOBIUM AUX AUBES DE TURBINE par G. GAUJE et R. BRUNETAUD Direction Technique de la SNECMA Résumé. 2014 L'emploi d'alliages de niobium à la place of niobium alloys instead of the current alloys with nickel or cobalt as parent metal for manufacturing

  10. Initiation aux applications de l'acupuncture en obsttrique 24 -25 novembre 2011

    E-print Network

    Brest, Université de

    Initiation aux applications de l'acupuncture en obstétrique 24 - 25 novembre 2011 Public concerné acupuncteurs Objectifs · Comprendre les principes essentiels de l'acupuncture appliquée à l'obstétrique · Connaître les effets antalgiques de l'acupuncture lors de l'accouchement mais aussi ses effets sur le col

  11. Journe de perfectionnement aux applications de l'acupuncture en obsttrique

    E-print Network

    Brest, Université de

    Journée de perfectionnement aux applications de l'acupuncture en obstétrique 1er décembre 2011 omnipraticiens acupuncteurs Objectifs : Préciser les bases essentielles des techniques d'acupuncture adaptées à l'obstétrique Préciser les meilleures indications de l'acupuncture en obstétrique Apporter une base rationnelle à l

  12. Binary Solid-Liquid Phase Equilibria

    ERIC Educational Resources Information Center

    Ellison, Herbert R.

    1978-01-01

    Indicates some of the information that may be obtained from a binary solid-liquid phase equilibria experiment and a method to write a computer program that will plot an ideal phase diagram to which the experimental results may be compared. (Author/CP)

  13. Enhancing solid-liquid interface thermal transport using self-assembled monolayers

    NASA Astrophysics Data System (ADS)

    Tian, Zhiting; Marconnet, Amy; Chen, Gang

    2015-05-01

    The thermal conductance across solid-liquid interfaces is of interest for many applications. Using time-domain thermoreflectance, we measure the thermal conductance across self-assembled monolayers, grown on Au, to ethanol. We systematically study the effect of different functional groups and the alkyl chain length on the thermal conductance. The results show that adding this extra molecular layer can enhance the thermal transport across the solid-liquid interface. While the enhancement is up to 5 times from hexanedithiol, the enhancement from hexanethiol, undecanethiol, and hexadecanethiol is approximately a factor of 2.

  14. PREDICTION OF PARTICLE CONCENTRATION PROFILES IN BINARY-SOLID LIQUID FLUIDIZED BED

    Microsoft Academic Search

    Mohammad Asif

    A simple mixing rule is presented here to predict the concentration profile of individual particle species in a binary-solid liquid fluidized bed from the information about the total solid concentration in the bed. Using the experimental data available in the literature, the applicability of this approach is demonstrated for the presence of different size particles in the bed. For the

  15. Solid-liquid interfacial energy of neopentylglycol.

    PubMed

    Ocak, Y; Akbulut, S; Ke?lio?lu, K; Mara?li, N

    2008-04-15

    The grain boundary groove shapes for equilibrated solid neopentylglycol (2,2-dimethyl-1,3-propanediol) (NPG) with its melt were directly observed by using a horizontal temperature gradient stage. From the observed grain boundary groove shapes, the Gibbs-Thomson coefficient (Gamma), solid-liquid interfacial energy (sigma(SL)), and grain boundary energy (sigma(gb)) of NPG have been determined to be (7.4+/-0.7)x10(-8) Km, (7.9+/-1.2)x10(-3) Jm(-2), and (15.4+/-2.5)x10(-3) Jm(-2), respectively. The ratio of thermal conductivity of equilibrated liquid phase to solid phase for the NPG has also been measured to be 1.07 at the melting temperature. PMID:18262201

  16. Convection-induced distortion of a solid-liquid interface

    Microsoft Academic Search

    R. J. Schaefer; S. R. Coriell

    1984-01-01

    Measurements of convective flow fields and solid-liquid interface shapes during the solidification of a pure and a slightly alloyed transparent material reveal that the convective transport of solute can cause a macroscopic depression to develop in the solid-liquid interface. This effect occurs under conditions close to those which are predicted to produce morphological instability of a planar interface. A cellular

  17. C. FLEURANT, G.TUCKER et H. VILES, Modle d'volution de paysages, application aux karsts en cockpit de Jamaque KARSTOLOGIA n49, 2007 33-42

    E-print Network

    Paris-Sud XI, Université de

    33 C. FLEURANT, G.TUCKER et H. VILES, Modèle d'évolution de paysages, application aux karsts en cockpit de Jamaïque KARSTOLOGIA n°49, 2007 · 33-42 Modèle d'évolution de paysages, application aux karsts chacune de ces compo- santes pourront conduire à un paysage différent: un karst à dolines, un fluvio

  18. Solid + liquid phase equilibria in the hydroxylammonium nitrate + water system

    Microsoft Academic Search

    Johanne I. Artman; J. Bevan Ott

    1989-01-01

    The binary solid + liquid phase diagram has been measured for the water + hydroxylammonium nitrate (HAN) system. The phase diagram is a simple eutectic type with the eutectic at 231.5 K (41.7°C) and a mole fraction HAN of 0.281 (wt fraction HAN - 0.676).The enthalpy of fusion of the HAN was determined from the solid + liquid results to

  19. Comparison study of solid-liquid separation techniques for oilfield pit closures

    Microsoft Academic Search

    A. C. Wojtanowicz; S. D. Field; M. C. Osterman

    1986-01-01

    Extensive bench-scale and full-scale experiments were conducted at the LSU Solids Control Environmental Laboratory in order to evaluate application of the solids-liquid separation technology to oilfield waste pit volume reduction. The experiments addressed chemical conditioning of various pit slurries such as water-base and oil-base mud reserve pit slurries, mixed sludge from offshore operations, and oil production pit slurry. Effective treatment

  20. In situ real-time monitoring of geometric, electronic, and molecular structures at solid/liquid interfaces

    NASA Astrophysics Data System (ADS)

    Uosaki, Kohei

    2015-03-01

    Many important processes take place at solid/liquid interfaces. To understand these processes, in situ real-time evaluation of the geometric, electronic, and molecular structures at solid/liquid interfaces at the atomic and molecular levels is essential. Owing to the presence of the liquid, however, techniques such as electron microscopy and low-energy electron diffraction, which are powerful tools for surface structural analysis in vacuum, cannot be used for solid/liquid interfaces. In this review, various techniques applicable to solid/liquid interfaces, including scanning probe microscopy, synchrotron-radiation-based X-ray techniques, and nonlinear spectroscopy, are briefly described. The characterization of the electrodeposition process of Pd layers on Au single-crystal electrode surfaces is presented as an example to demonstrate the importance of using multiple techniques in an integrated manner to understand the processes at solid/liquid interfaces. This is a translated version of the original paper which appeared in Oyo Buturi 82, 106 (2013) [in Japanese] with some modifications.

  1. Application of the New Decommissioning Regulation to the Nuclear Licensed Facilities (NLF) at Fontenay-aux-Roses's Nuclear Center (CEA)

    Microsoft Academic Search

    Josiane Sauret; Laurence Piketty; Michel Jeanjacques

    2008-01-01

    This abstract describes the application of the new decommissioning regulation on all Nuclear Licensed Facilities (NLF is to say INB in French) at Fontenay-aux-Roses's Center (CEA\\/FAR). The decommissioning process has been applied in six buildings which are out of the new nuclear perimeter proposed (buildings no 7, no 40, no 94, no 39, no 52\\/1 and no 32) and three

  2. Etude sur les tendons en materiaux composites et leur application aux ancrages postcontraints

    NASA Astrophysics Data System (ADS)

    Chennouf, Adil

    L'objectif general de la presente these est d'evaluer le comportement a l'arrachement et au fluage d'ancrages injectes constitues de tendons en materiaux composites afin d'etablir des recommandations plus appropriees et realistes pour le dimensionnement et la conception. Quatre types de tendons en materiaux composites, deux a base de fibres d'aramide et deux a base de fibres de carbone, ont ete utilises dans l'etude. Les travaux de recherche de cette these ont porte notamment sur: (I) Une caracterisation physique et mecanique des tendons en materiaux composites utilises dans l'etude. (II) Une etude en laboratoire sur les coulis de scellement. La premiere etape de cette etude a concerne le developpement d'un coulis de scellement performant adapte aux tendons en materiaux composites et a differentes situations d'injection. La seconde etape a traite des essais de caracterisations physique et mecanique du coulis de scellement developpe comparativement a trois coulis de scellement usuels d'un meme rapport E/L de 0,4. (III) Une etude sur des modeles reduits d'ancrages injectes. (IV) Une etude sur des modeles d'ancrages a grande echelle. La synthese de ces etudes a permis d'enoncer les principales conclusions suivantes: (1) Les valeurs moyennes des charges de rupture des tendons en materiaux composites ont ete de 1% a 29% superieures a celles specifiees par les manufacturiers. (2) L'etude sur les coulis de scellement a permis le developpement de coulis de ciment repondant aux criteres fixes, soient une grande stabilite, une bonne fluidite, une legere expansion et de bonnes caracteristiques mecaniques. (3) Les tendons en materiaux composites ont montre des contraintes d'adherence maximum superieures a celles des tendons en acier. (4) Le type de fibre, la configuration et le fini de surface des tendons en materiaux composites gouvernent leur resistance a l'adherence. (5) L'introduction de sable et d'autres ajouts comme les fines de silice et la poudre d'aluminium au coulis de ciment a permis d'ameliorer la resistance a l'adherence. (6) Il existe une relation lineaire entre la charge maximum et la longueur ancree des tendons. Des equations sont proposees. (7) La capacite a l'arrachement des ancrages injectes augmente avec l'augmentation du module d'elasticite du milieu encaissant. (8) Les mono-tendons et multi-tendons en materiaux composites injectes sur 1000 mm ont montre des comportements a l'arrachement acceptables conformement aux codes. (9) Les rigidites apparentes des tendons a base de fibres d'aramide sont de trois a cinq fois inferieures a celles des tendons a base de fibres de carbone. (10) L'amorce de la decohesion en haut de la zone ancree ne semble se produire qu'au-dela d'une charge de 0,35 fpu pour les tendons a base de fibres de carbone alors qu'elle prend naissance des l'application de la charge pour les tendons a base de fibres d'aramide. (11) Le taux de fluage depend du niveau de chargement ainsi que des caracteristiques geometriques et mecaniques de l'ancrage (type de fibres, fini de surface, nombre de tendons, etc.). (12) Des equations regissant le comportement au fluage des tendons en materiaux composites ont ete etablies pour une periode d'essai de 60 mn. (Abstract shortened by UMI.)

  3. Flow pattern maps for solid-liquid flow in pipes

    Microsoft Academic Search

    P. Doron; D. Barnea

    1996-01-01

    Various flow patterns can be encountered in a solid-liquid pipeline, which affect the hydrodynamic characteristics of the flow. A method for displaying their range of existence by means of flow maps is presented. The maps are drawn from the results of a phenomenological model. The effect of the various operational conditions on the flow pattern transitions are obtained easily using

  4. Calculation of solid-liquid interfacial free energy of Cu by two different methods

    NASA Astrophysics Data System (ADS)

    Zhou, Huaguang; Lin, Xin; Wang, Meng; Huang, Weidong

    2013-08-01

    Both the solid-liquid interfacial free energy and Turnbull coefficient calculated by the capillary fluctuation method (CFM) are consistent with those by the critical nucleus method (CNM). The calculated solid-liquid interfacial free energy by CNM is more accurate than that by CFM, but CFM can give the anisotropy parameter of solid-liquid interfacial free energy while CNM can not. Thus, these two methods can be combined to calculate the solid-liquid interfacial free energy and its anisotropy.

  5. Solid-Liquid Separation of Animal Manure and Wastewater 

    E-print Network

    Mukhtar, Saqib; Sweeten, John M.; Auvermann, Brent W.

    1999-10-19

    high initial costs, maintenance and energy requirements. ? Coagulation Flocculation. A relatively new tech- nique for solid-liquid separation uses chemicals to aggregate suspended solids (coagulation) to form settleable particles and to convert... compacts and removes water from these solids during transport. Chemical treatment Researchers are studying the processes of coagula- tion and flocculation of particles, which use chemicals to help separate solids from liquids in animal manure. Coagulation...

  6. Solid-liquid critical behavior of water in nanopores.

    PubMed

    Mochizuki, Kenji; Koga, Kenichiro

    2015-07-01

    Nanoconfined liquid water can transform into low-dimensional ices whose crystalline structures are dissimilar to any bulk ices and whose melting point may significantly rise with reducing the pore size, as revealed by computer simulation and confirmed by experiment. One of the intriguing, and as yet unresolved, questions concerns the observation that the liquid water may transform into a low-dimensional ice either via a first-order phase change or without any discontinuity in thermodynamic and dynamic properties, which suggests the existence of solid-liquid critical points in this class of nanoconfined systems. Here we explore the phase behavior of a model of water in carbon nanotubes in the temperature-pressure-diameter space by molecular dynamics simulation and provide unambiguous evidence to support solid-liquid critical phenomena of nanoconfined water. Solid-liquid first-order phase boundaries are determined by tracing spontaneous phase separation at various temperatures. All of the boundaries eventually cease to exist at the critical points and there appear loci of response function maxima, or the Widom lines, extending to the supercritical region. The finite-size scaling analysis of the density distribution supports the presence of both first-order and continuous phase changes between solid and liquid. At around the Widom line, there are microscopic domains of two phases, and continuous solid-liquid phase changes occur in such a way that the domains of one phase grow and those of the other evanesce as the thermodynamic state departs from the Widom line. PMID:26100904

  7. Final Report: Thermal Conductance of Solid-Liquid Interfaces

    Microsoft Academic Search

    David Cahil; Paul Braun

    2006-01-01

    Research supported by this grant has significantly advanced fundamental understanding of the thermal conductance of solid-liquid interfaces, and the thermal conductivity of nanofluids and nanoscale composite materials. ;\\u000a;\\u000a The thermal conductance of interfaces between carbon nanotubes and a surrounding matrix of organic molecules is exceptionally small and this small value of the interface conductance limits the enhancement in thermal

  8. Application of the New Decommissioning Regulation to the Nuclear Licensed Facilities (NLF) at Fontenay-aux-Roses's Nuclear Center (CEA)

    SciTech Connect

    Sauret, Josiane [Commissariat a l'Energie Atomique, Direction du Centre de Fontenay-aux-Roses, Cellule de Surete nucleaire, de controle des Matieres, de controle des Transports et de la Qualite, 18 route du Panorama BP 6 - 92265 Fontenay-aux-Roses Cedex (France); Piketty, Laurence; Jeanjacques, Michel [Commissariat a l'Energie Atomique, Direction de l'Energie Nucleaire, Direction deleguee des Activites Nucleaires de Saclay, Departement des Reacteurs et des Services Nucleaires, service d'Assainissement de Fontenay-aux-Roses, 18 route du Panorama BP 6 - 92265 Fontenay-aux-Roses Cedex (France)

    2008-01-15

    This abstract describes the application of the new decommissioning regulation on all Nuclear Licensed Facilities (NLF is to say INB in French) at Fontenay-aux-Roses's Center (CEA/FAR). The decommissioning process has been applied in six buildings which are out of the new nuclear perimeter proposed (buildings no 7, no 40, no 94, no 39, no 52/1 and no 32) and three buildings have been reorganized (no 54, no 91 and no 53 instead of no 40 and no 94) in order to increase the space for temporary nuclear waste disposal and to reduce the internal transports of nuclear waste on the site. The advantages are the safety and radioprotection improvements and a lower operating cost. A global safety file was written in 2002 and 2003 and was sent to the French Nuclear Authority on November 2003. The list of documents required is given in the paragraph I of this paper. The main goals were two ministerial decrees (one decree for each NLF) getting the authorization to modify the NLF perimeter and to carry out cleaning and dismantling activities leading to the whole decommissioning of all NLF. Some specific authorizations were necessary to carry out the dismantling program during the decommissioning procedure. They were delivered by the French Nuclear Safety Authority (FNSA) or with limited delegation by the General Executive Director (GED) on the CEA Fontenay-aux-Roses's Center, called internal authorization. Some partial dismantling or decontamination examples are given below: - evaporator for the radioactive liquid waste treatment station (building no 53): FNSA authorization: phase realised in 2002/2003. - disposal tanks for the radioactive liquid waste treatment station (building no 53) FNSA authorization: phase realised in 2004, - incinerator for the radioactive solid waste treatment station (building no 07): FNSA authorization: operation realised in 2004, - research equipments in the building no. 54 and building no. 91: internal authorization ; realised in 2005, - sample-taking to characterize solvent contained in one tank of Petrus installation (NLF 57, building 18) for radiological and chemical analysis needed to prepare the treatment and the evacuation of these wastes : internal authorization ; realised in june 2005. It was possible to plan the whole decommissioning process on the Nuclear Licensed Facilities of Fontenay-aux-Roses's Center (CEA/FAR) taking into account the French new regulation and to plan a coherent and continue program activity for the dismantling process. For the program not to be interrupted during the administrative process (2003-2006), specific authorisations have been delivered by the French Nuclear Safety Authority or by the General Executive Director (GED) on the CEA Fontenay-aux- Roses's Center (internal authorization). The time schedule to complete the entire program is until 2017 for NLF 'Procede' (NLF no 165) and until 2018 for NLF 'Support' (NLF no 166). Since 1999, an annual press meeting has been organised by the Fontenay-aux-Roses's Center Head Executive Manager.

  9. Solid-liquid coexistence of polydisperse fluids via simulation

    NASA Astrophysics Data System (ADS)

    Wilding, Nigel B.

    2009-03-01

    We describe a simulation method for the accurate study of the equilibrium freezing properties of polydisperse fluids under the experimentally relevant condition of fixed polydispersity. The approach is based on the phase switch Monte Carlo method of Wilding and Bruce [Phys. Rev. Lett. 85, 5138 (2000)]. This we have generalized to deal with particle size polydispersity by incorporating updates which alter the diameter ? of a particle, under the control of a distribution of chemical potential differences ?˜(?). Within the resulting isobaric semi-grand-canonical ensemble, we detail how to adapt ?˜(?) and the applied pressure such as to study coexistence, while ensuring that the ensemble averaged density distribution ?(? ) matches a fixed functional form. Results are presented for the effects of small degrees of polydispersity on the solid-liquid transition of soft spheres.

  10. Solid-liquid coexistence of polydisperse fluids via simulation.

    PubMed

    Wilding, Nigel B

    2009-03-14

    We describe a simulation method for the accurate study of the equilibrium freezing properties of polydisperse fluids under the experimentally relevant condition of fixed polydispersity. The approach is based on the phase switch Monte Carlo method of Wilding and Bruce [Phys. Rev. Lett. 85, 5138 (2000)]. This we have generalized to deal with particle size polydispersity by incorporating updates which alter the diameter sigma of a particle, under the control of a distribution of chemical potential differences mu(sigma). Within the resulting isobaric semi-grand-canonical ensemble, we detail how to adapt mu(sigma) and the applied pressure such as to study coexistence, while ensuring that the ensemble averaged density distribution rho(sigma) matches a fixed functional form. Results are presented for the effects of small degrees of polydispersity on the solid-liquid transition of soft spheres. PMID:19292519

  11. Solid/liquid interfacial free energies in binary systems

    NASA Technical Reports Server (NTRS)

    Nason, D.; Tiller, W. A.

    1973-01-01

    Description of a semiquantitative technique for predicting the segregation characteristics of smooth interfaces between binary solid and liquid solutions in terms of readily available thermodynamic parameters of the bulk solutions. A lattice-liquid interfacial model and a pair-bonded regular solution model are employed in the treatment with an accommodation for liquid interfacial entropy. The method is used to calculate the interfacial segregation and the free energy of segregation for solid-liquid interfaces between binary solutions for the (111) boundary of fcc crystals. The zone of compositional transition across the interface is shown to be on the order of a few atomic layers in width, being moderately narrower for ideal solutions. The free energy of the segregated interface depends primarily upon the solid composition and the heats of fusion of the component atoms, the composition difference of the solutions, and the difference of the heats of mixing of the solutions.

  12. Methods and systems for monitoring a solid-liquid interface

    DOEpatents

    Stoddard, Nathan G. (Gettysburg, PA); Clark, Roger F. (Frederick, MD)

    2011-10-04

    Methods and systems are provided for monitoring a solid-liquid interface, including providing a vessel configured to contain an at least partially melted material; detecting radiation reflected from a surface of a liquid portion of the at least partially melted material; providing sound energy to the surface; measuring a disturbance on the surface; calculating at least one frequency associated with the disturbance; and determining a thickness of the liquid portion based on the at least one frequency, wherein the thickness is calculated based on L=(2m-1)v.sub.s/4f, where f is the frequency where the disturbance has an amplitude maximum, v.sub.s is the speed of sound in the material, and m is a positive integer (1, 2, 3, . . . ).

  13. Probing Hydrophilic Interface of Solid/Liquid-Water by Nanoultrasonics

    PubMed Central

    Mante, Pierre-Adrien; Chen, Chien-Cheng; Wen, Yu-Chieh; Chen, Hui-Yuan; Yang, Szu-Chi; Huang, Yu-Ru; -Ju Chen, I.; Chen, Yun-Wen; Gusev, Vitalyi; Chen, Miin-Jang; Kuo, Jer-Lai; Sheu, Jinn-Kong; Sun, Chi-Kuang

    2014-01-01

    Despite the numerous devoted studies, water at solid interfaces remains puzzling. An ongoing debate concerns the nature of interfacial water at a hydrophilic surface, whether it is more solid-like, ice-like, or liquid-like. To answer this question, a complete picture of the distribution of the water molecule structure and molecular interactions has to be obtained in a non-invasive way and on an ultrafast time scale. We developed a new experimental technique that extends the classical acoustic technique to the molecular level. Using nanoacoustic waves with a femtosecond pulsewidth and an ångström resolution to noninvasively diagnose the hydration structure distribution at ambient solid/water interface, we performed a complete mapping of the viscoelastic properties and of the density in the whole interfacial water region at hydrophilic surfaces. Our results suggest that water in the interfacial region possesses mixed properties and that the different pictures obtained up to now can be unified. Moreover, we discuss the effect of the interfacial water structure on the abnormal thermal transport properties of solid/liquid interfaces. PMID:25176017

  14. Toward a detailed characterization of oil adsorbates as "solid liquids".

    PubMed

    Kutza, Claudia; Metz, Hendrik; Kutza, Johannes; Syrowatka, Frank; Mäder, Karsten

    2013-05-01

    Solid lipid formulation systems are used to overcome oral bioavailability problems of poorly water-soluble drugs. One promising process is the conversion of a liquid lipid system in a free flowing powder by use of adsorbing excipients. The aim of this study was the detailed characterization of solid-liquid interactions in oil adsorbed to Fujicalin and Neusilin which were manufactured by means of dual asymmetric centrifugation or conventional mortar/pestle blending. The adsorption strength of the excipients was investigated by Benchtop-NMR and ESR spectroscopy revealing the highest adsorption power for the Neusilin products. The adsorbate production methods as well as the storage of the excipients impact their adsorption properties. Environmental scanning electron microscopy (ESEM) and confocal laser scanning microscopy (CLSM) show that dual asymmetric centrifugation leads to a smoothing of the particle surface, whereas the mortar/pestle blending results in an uneven surface and particle destruction. The oil distribution at the particles is inhomogeneous for both production methods. The micropolarity of the adsorbed oil was investigated by ESR spectroscopy and multispectral fluorescence imaging. The adsorbing process on Neusilin leads to an increased micropolarity of the oil component. The release of the oil component in aqueous media could be verified by Benchtop-NMR and multispectral fluorescence imaging. PMID:23275113

  15. Probing Hydrophilic Interface of Solid/Liquid-Water by Nanoultrasonics

    NASA Astrophysics Data System (ADS)

    Mante, Pierre-Adrien; Chen, Chien-Cheng; Wen, Yu-Chieh; Chen, Hui-Yuan; Yang, Szu-Chi; Huang, Yu-Ru; -Ju Chen, I.; Chen, Yun-Wen; Gusev, Vitalyi; Chen, Miin-Jang; Kuo, Jer-Lai; Sheu, Jinn-Kong; Sun, Chi-Kuang

    2014-09-01

    Despite the numerous devoted studies, water at solid interfaces remains puzzling. An ongoing debate concerns the nature of interfacial water at a hydrophilic surface, whether it is more solid-like, ice-like, or liquid-like. To answer this question, a complete picture of the distribution of the water molecule structure and molecular interactions has to be obtained in a non-invasive way and on an ultrafast time scale. We developed a new experimental technique that extends the classical acoustic technique to the molecular level. Using nanoacoustic waves with a femtosecond pulsewidth and an ångström resolution to noninvasively diagnose the hydration structure distribution at ambient solid/water interface, we performed a complete mapping of the viscoelastic properties and of the density in the whole interfacial water region at hydrophilic surfaces. Our results suggest that water in the interfacial region possesses mixed properties and that the different pictures obtained up to now can be unified. Moreover, we discuss the effect of the interfacial water structure on the abnormal thermal transport properties of solid/liquid interfaces.

  16. Interaction of Porosity with a Planar Solid/Liquid Interface

    NASA Technical Reports Server (NTRS)

    Catalina, Adrian V.; Stefanescu, Doru M.; Sen, Subhayu; Kaukler, William F.

    2004-01-01

    In this article, an investigation of the interaction between gas porosity and a planar solid/liquid (SL) interface is reported. A two-dimensional numerical model able to accurately track sharp SL interfaces during solidification of pure metals and alloys is proposed. The finite-difference method and a rectangular undeformed grid are used for computation. The SL interface is described through the points of intersection with the grid lines. Its motion is determined by the thermal and solute gradients at each particular point. Changes of the interface temperature because of capillarity or solute redistribution as well as any perturbation of the thermal and solute field produced by the presence of non-metallic inclusions can be computed. To validate the model, the dynamics of the interaction between a gas pore and a solidification front in metal alloys was observed using a state of the art X-ray transmission microscope (XTM). The experiments included observation of the distortion of the SL interface near a pore, real-time measurements of the growth rate, and the change in shape of the porosity during interaction with the SL interface in pure Al and Al-0.25 wt pct Au alloy. In addition, porosity-induced solute segregation patterns surrounding a pore were also quantified.

  17. Final Report: Thermal Conductance of Solid-Liquid Interfaces

    SciTech Connect

    Cahil, David, G.; Braun, Paul, V.

    2006-05-31

    Research supported by this grant has significantly advanced fundamental understanding of the thermal conductance of solid-liquid interfaces, and the thermal conductivity of nanofluids and nanoscale composite materials. • The thermal conductance of interfaces between carbon nanotubes and a surrounding matrix of organic molecules is exceptionally small and this small value of the interface conductance limits the enhancement in thermal conductivity that can be achieved by loading a fluid or a polymer with nanotubes. • The thermal conductance of interfaces between metal nanoparticles coated with hydrophilic surfactants and water is relatively high and surprisingly independent of the details of the chemical structure of the surfactant. • We extended our experimental methods to enable studies of planar interfaces between surfactant-coated metals and water where the chemical functionalization can be varied between strongly hydrophobic and strongly hydrophilic. The thermal conductance of hydrophobic interfaces establishes an upper-limit of 0.25 nm on the thickness of the vapor-layer that is often proposed to exist at hydrophobic interfaces. • Our high-precision measurements of fluid suspensions show that the thermal conductivity of fluids is not significantly enhanced by loading with a small volume fraction of spherical nanoparticles. These experimental results directly contradict some of the anomalous results in the recent literature and also rule-out proposed mechanisms for the enhanced thermal conductivity of nanofluids that are based on modification of the fluid thermal conductivity by the coupling of fluid motion and the Brownian motion of the nanoparticles.

  18. Mathematical Modeling and Numerical Simulation of Liquid-Solid and Solid-Liquid Phase Change

    E-print Network

    Joy, Aaron

    2013-08-31

    This thesis presents numerical simulations of liquid-solid and solid-liquid phase change processes using mathematical models in Lagrangian and Eulerian descriptions. The mathematical models are derived by assuming a smooth interface (or transition...

  19. CFD modeling of solid–liquid fluidized beds of mono and binary particle mixtures

    Microsoft Academic Search

    Rupesh K. Reddy; Jyeshtharaj B. Joshi

    2009-01-01

    CFD simulation of bed expansion of mono size solid–liquid fluidized beds has been performed in creeping, transition and turbulent flow regimes, where Reynolds number (Re?=dpVS??L\\/?L) has been varied from 0.138 to 1718. It has been observed that the predicted values of bed voidage using the drag law of Joshi [1983. Solid–liquid fluidized beds: some design aspects. Chemical Engineering Research and

  20. CFD Analysis of Solid-Liquid Suspension Flow in a Horizontal Pipe

    Microsoft Academic Search

    Arti Tiwari; Triloki Nath

    2010-01-01

    The present work focuses on the three-dimensional modeling of the solid -liquid suspension flow based on the Eulerian-Eularian multiphase flow model. The k-? turbulence model and particle- induced turbulence model were used to simulate the solid-liquid suspension flow. The momentum transfer between the solid and liquid phases including drag force, shear induced lift force and virtual mass force, together with

  1. Coarsening in Solid Liquid Systems: A Verification of Fundamental Theory

    NASA Astrophysics Data System (ADS)

    Thompson, John D.

    Coarsening is a process that occurs in nearly all multi-phase materials in which the total energy of a system is reduced through the reduction of total interfacial energy. The theoretical description of this process is of central importance to materials design, yet remains controversial. In order to directly compare experiment to theoretical predictions, low solid volume fraction PbSn alloys were coarsened in a microgravity environment aboard the International Space Station (ISS) as part of the Coarsening in Solid Liquid Mixtures (CSLM) project. PbSn samples with solid volume fractions of 15%, 20% and 30% were characterized in 2D and 3D using mechanical serial sectioning. The systems were observed in the self-similar regime predicted by theory and the particle size and particle density obeyed the temporal power laws predicted by theory. However, the magnitudes of the rate constants governing those temporal laws as well as the forms of the particle size distributions were not described well by theoretical predictions. Additionally, in the 30% solid volume fraction system, the higher volume fraction results in a non-spherical particle shape and a more closely packed spatial distribution. The presence of slow particle motion induced by vibrations on the ISS is presented as an explanation for this discrepancy. To model the effect of this particle motion, the Akaiwa-Voorhees multiparticle diffusion simulations are modified to treat coarsening in the presence of a small convection term, such as that of sedimentation, corresponding to low Peclet numbers. The simulations indicate that the particle size dependent velocity of the sedimentation increases the rate at which the system coarsens. This is due to the larger particles traveling farther than normal, resulting in them encountering more small particles, which favors their growth. Additionally, sedimentation resulted in broader PSDs with a peak located at the average particle size. When the simulations are modified to account for the particle sedimentation, the measurements for the 15% and 20% system are in excellent agreement with the theoretical predictions for both the rate constants and the PSDs. There is good agreement with the 30% system as well, though the simulations are less valid at this volume fraction.

  2. Dynamic covalent chemistry of bisimines at the solid/liquid interface monitored by scanning tunnelling microscopy.

    PubMed

    Ciesielski, Artur; El Garah, Mohamed; Haar, Sébastien; Kova?í?ek, Petr; Lehn, Jean-Marie; Samorì, Paolo

    2014-11-01

    Dynamic covalent chemistry relies on the formation of reversible covalent bonds under thermodynamic control to generate dynamic combinatorial libraries. It provides access to numerous types of complex functional architectures, and thereby targets several technologically relevant applications, such as in drug discovery, (bio)sensing and dynamic materials. In liquid media it was proved that by taking advantage of the reversible nature of the bond formation it is possible to combine the error-correction capacity of supramolecular chemistry with the robustness of covalent bonding to generate adaptive systems. Here we show that double imine formation between 4-(hexadecyloxy)benzaldehyde and different ?,?-diamines as well as reversible bistransimination reactions can be achieved at the solid/liquid interface, as monitored on the submolecular scale by in situ scanning tunnelling microscopy imaging. Our modular approach enables the structurally controlled reversible incorporation of various molecular components to form sophisticated covalent architectures, which opens up perspectives towards responsive multicomponent two-dimensional materials and devices. PMID:25343608

  3. Poly(phenylene Sulfide) (pps) Membrane Formation via Solid-Liquid Thermally Induced Phase Separation.

    NASA Astrophysics Data System (ADS)

    Chiang, Chung-Yuan

    1995-01-01

    Microporous polymeric membranes of improved thermal stability and chemical resistance were formed via Thermally Induced Phase Separation (TIPS) process. Specifically, poly(phenylene sulfide) (PPS) membranes were formed using 4-benzoylbiphenyl (BBP) as the diluent. The overall objective of the proposed research was to produce porous PPS membranes by the solid-liquid TIPS process. Specifically, the objective was to investigate the feasibility of controlling membrane structure by controlling the nucleation density ( eta). Control over eta (hence the morphology) was achieved by choosing proper combinations of process parameters, such as polymer concentration, dissolution temperature, crystallization temperature, dissolution time, and crystallization time. Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM) and optical microscopy (OM) were used to obtain the required data. A new mathematical model was developed to predict the eta for a polymer-diluent system. The new model overcomes the limitations imposed by the simplified Avrami equation. The new model differs from the classical Avrami theory in its treatment of the dependence of growth probabilities on the change in polymer concentration as crystallization develops. The theory includes treatment of both homogeneous and heterogeneous nucleation, arbitrary growth shapes (e.g., axialites), and secondary crystallization. With the developments presented in this dissertation, process engineers can easily select the correct process parameters to fulfill the specifications of microporous membranes for specific applications.

  4. Solid-liquid phase equilibrium for binary Lennard-Jones mixtures

    NASA Astrophysics Data System (ADS)

    Hitchcock, Monica R.; Hall, Carol K.

    1999-06-01

    Solid-liquid phase diagrams are calculated for binary mixtures of Lennard-Jones spheres using Monte Carlo simulation and the Gibbs-Duhem integration technique of Kofke. We calculate solid-liquid phase diagrams for the model Lennard-Jones mixtures: argon-methane, krypton-methane, and argon-krypton, and compare our simulation results with experimental data and with Cottin and Monson's recent cell theory predictions. The Lennard-Jones model simulation results and the cell theory predictions show qualitative agreement with the experimental phase diagrams. One of the mixtures, argon-krypton, has a different phase diagram than its hard-sphere counterpart, suggesting that attractive interactions are an important consideration in determining solid-liquid phase behavior. We then systematically explore Lennard-Jones parameter space to investigate how solid-liquid phase diagrams change as a function of the Lennard-Jones diameter ratio, ?11/?22, and well-depth ratio, ?11/?22. This culminates in an estimate of the boundaries separating the regions of solid solution, azeotrope, and eutectic solid-liquid phase behavior in the space spanned by ?11/?22 and ?11/?22 for the case ?11/?22<0.85.

  5. Introduction aux Systmes Temps Rel Nicolas NAVET

    E-print Network

    Navet, Nicolas

    Introduction aux Systèmes Temps Réel Nicolas NAVET 2010/2011 http://www.loria.fr/~nnavet Introduction aux systèmes temps réel #12;Plan du cours 1. Systèmes temps réel : exemples et fondamentaux 2. Conception des applications temps réel : quelles techniques pour vérier le respect des contraintes ? 3

  6. Solid-liquid critical behavior of a cylindrically confined Lennard-Jones fluid.

    PubMed

    Mochizuki, Kenji; Koga, Kenichiro

    2015-07-01

    Extensive molecular dynamics simulations have been performed to study the phase behavior of Lennard-Jones particles confined in a quasi-one-dimensional hydrophobic nanopore. We provide unambiguous evidence for a solid-liquid critical point by investigating (i) isotherms in the pressure-volume plane, (ii) the spontaneous solid-liquid phase separation below a certain temperature, (iii) diverging heat capacity and isothermal compressibility as a certain point is approached, (iv) continuous change of dynamical and structural properties above the point, (v) the finite-size scaling analysis of the density distribution below and above the point. The result combined with earlier studies of confined water suggests that the solid-liquid critical point is not uncommon in quasi-one- and quasi-two-dimensional fluids. PMID:26107091

  7. CFD Analysis of Solid-Liquid Suspension Flow in a Horizontal Pipe

    NASA Astrophysics Data System (ADS)

    Tiwari, Arti; Nath, Triloki

    2010-10-01

    The present work focuses on the three-dimensional modeling of the solid -liquid suspension flow based on the Eulerian-Eularian multiphase flow model. The k-? turbulence model and particle- induced turbulence model were used to simulate the solid-liquid suspension flow. The momentum transfer between the solid and liquid phases including drag force, shear induced lift force and virtual mass force, together with buoyancy force were considered in the model. The simulation geometry focuses on a horizontal pipe. The simulation results showed that the suspension status of solid particles depends on the input flow rate.

  8. Binary Solid-Liquid Phase Diagram of Phenol and t-Butanol: An Undergraduate Physical Chemistry Experiment

    ERIC Educational Resources Information Center

    Xu, Xinhua; Wang, Xiaogang; Wu, Meifen

    2014-01-01

    The determination of the solid-liquid phase diagram of a binary system is always used as an experiment in the undergraduate physical chemistry laboratory courses. However, most phase diagrams investigated in the lab are simple eutectic ones, despite the fact that complex binary solid-liquid phase diagrams are more common. In this article, the…

  9. Evaluation of target efficiencies for solid-liquid separation steps in biofuels production.

    PubMed

    Kochergin, Vadim; Miller, Keith

    2011-01-01

    Development of liquid biofuels has entered a new phase of large scale pilot demonstration. A number of plants that are in operation or under construction face the task of addressing the engineering challenges of creating a viable plant design, scaling up and optimizing various unit operations. It is well-known that separation technologies account for 50-70% of both capital and operating cost. Additionally, reduction of environmental impact creates technological challenges that increase project cost without adding to the bottom line. Different technologies vary in terms of selection of unit operations; however, solid-liquid separations are likely to be a major contributor to the overall project cost. Despite the differences in pretreatment approaches, similar challenges arise for solid-liquid separation unit operations. A typical process for ethanol production from biomass includes several solid-liquid separation steps, depending on which particular stream is targeted for downstream processing. The nature of biomass-derived materials makes it either difficult or uneconomical to accomplish complete separation in a single step. Therefore, setting realistic efficiency targets for solid-liquid separations is an important task that influences overall process recovery and economics. Experimental data will be presented showing typical characteristics for pretreated cane bagasse at various stages of processing into cellulosic ethanol. Results of generic material balance calculations will be presented to illustrate the influence of separation target efficiencies on overall process recoveries and characteristics of waste streams. PMID:20607445

  10. Different gastric, pancreatic, and biliary responses to solid-liquid or homogenized meals

    Microsoft Academic Search

    Juan-R. Malagelada; Vay L. W. Go; W. H. J. Summerskill

    1979-01-01

    We have compared responses to an ordinary solid-liquid (S) meal and to a homogenized (H) meal of identical composition (sirloin steak, bread, butter, ice cream with chocolate syrup, and water) by measuring simultaneously postprandial gastric, pancreatic, and biliary functions by marker-perfusion techniques. Responses to each (S or H) meals differed strikingly both in magnitude and pattern. S meals elicited a

  11. All about Solids, Liquids & Gases. Physical Science for Children[TM]. Schlessinger Science Library. [Videotape].

    ERIC Educational Resources Information Center

    2000

    In All About Solids, Liquids and Gases, young students will be introduced to the three common forms of matter. They'll learn that all things are made up of tiny particles called atoms and that the movement of these particles determines the form that matter takes. In solids, the particles are packed tightly together and move very little. The…

  12. To appear in ACM Transactions on Graphics Simulating Liquids and Solid-Liquid Interactions with

    E-print Network

    California at Berkeley, University of

    , and Pixar. Correspondence author: J. F. O'Brien, University of California, Berkeley, CA; email: job with Lagrangian Meshes Pascal Clausen, Martin Wicke, Jonathan R. Shewchuk, and James F. O'Brien University, M., Shewchuk, J. R., and O'Brien, J. F. 2013. Simulat- ing Liquids and Solid-Liquid Interactions

  13. New materials for solar thermal storage—solid\\/liquid transitions in fatty acid esters

    Microsoft Academic Search

    R Nikoli?; M Marinovi?-Cincovi?; S Gadžuri?; I. J Zsigrai

    2003-01-01

    Solid\\/liquid transitions were studied by DSC measurements in the following fatty acid esters: methyl stearate, methyl palmitate, cetyl stearate, cetyl palmitate and their binary mixtures. Four systems, with phase transition temperature close to room temperature and with high enthalpy of transition and low hysteresis, were selected for further studies relevant to passive solar thermal storage. The selected systems were: methyl

  14. Adsorption\\/aggregation of surfactants and their mixtures at solid–liquid interfaces

    Microsoft Academic Search

    P. Somasundaran; L. Huang

    2000-01-01

    Adsorption of surfactants and polymers at solid–liquid interfaces is used widely to modify interfacial properties in a variety of industrial processes such as flotation, ceramic processing, flocculation\\/dispersion, personal care product formulation and enhanced oil recovery. The behavior of surfactants and polymers at interfaces is determined by a number of forces, including electrostatic attraction, covalent bonding, hydrogen bonding, hydrophobic bonding, and

  15. Solid-Liquid and Liquid-Liquid Mixing Laboratory for Chemical Engineering Undergraduates

    ERIC Educational Resources Information Center

    Pour, Sanaz Barar; Norca, Gregory Benoit; Fradette, Louis; Legros, Robert; Tanguy, Philippe A.

    2007-01-01

    Solid-liquid and liquid-liquid mixing experiments have been developed to provide students with a practical experience on suspension and emulsification processes. The laboratory focuses on the characterization of the process efficiency, specifically the influence of the main operating parameters and the effect of the impeller type. (Contains 2…

  16. Transient state study of electric motor heating and phase change solid-liquid cooling

    Microsoft Academic Search

    J. Bellettre; V. Sartre; F. Biais; A. Lallemand

    1997-01-01

    This study reports on modelling of an autosynchronous electric motor stator, operating at transient state. The developed model, of the nodal type, includes around 20 nodes. The simulations showed that hot spots are localized on the winding heads and led to the choice of a solid-liquid phase change cooling system. The comparison between simulation and experiment permitted the identification of

  17. Membrane-based separations for solid\\/liquid clarification and protein purification

    Microsoft Academic Search

    Matthew Thomas Aspelund

    2010-01-01

    Recombinant protein technology has become increasingly important in recent years. Recombinant proteins can be found in everything from pharmaceuticals to detergents. The increasing demand and the high cost associated with the production and purification of recombinant proteins highlights the need to develop efficient and inexpensive methods for the solid\\/liquid clarification and purification of these proteins. Membrane technologies, which offer the

  18. Gemini Surfactants at Solid-Liquid Interfaces: Control of Interfacial Aggregate Geometry

    E-print Network

    Aksay, Ilhan A.

    Gemini Surfactants at Solid-Liquid Interfaces: Control of Interfacial Aggregate Geometry S. Manne of surfactant geometry by using gemini surfactants with varying tail and spacer lengths. On the anionic cleavage that are surface-controlled and relatively independent of surfactant geometry. This interaction is used

  19. Measurement and correlation of solid–liquid equilibria of Irganox 1010 with n-hexane

    Microsoft Academic Search

    Dongwei Wei; Limei Chen; Jingjing Xu; Fusheng Li

    2009-01-01

    Solid–liquid equilibria (SLE) for the binary mixtures of Irganox 1010 with n-hexane have been measured using a method in which an excess amount of solute was equilibrated with the alkane solution. The liquid concentrations of the Irganox 1010 in the saturated solution were analyzed by UV spectrometry. Activity coefficients for Irganox 1010 have been calculated by means of the Wilson,

  20. Document de Recherche "La fiscalit des fonds de pension aux Etats-Unis"

    E-print Network

    Paris-Sud XI, Université de

    Document de Recherche n° 2006-16 "La fiscalité des fonds de pension aux Etats-Unis" Anne LAVIGNE fonds de pension aux Etats-Unis 1 Anne Lavigne Laboratoire d'économie d'Orléans, UMR 6221 ­ CNRS dispositifs fiscaux applicables aux fonds de pension, que ces dispositifs concernent les employés, les

  1. Electric current effects on solid-solid and solid-liquid metallic reactions

    NASA Astrophysics Data System (ADS)

    Zhao, Jinfeng

    The interactions at high temperatures between contacting dissimilar metals and the nature of the phases formed from such interactions are of importance in a variety of applications. Solid-solid interactions are important in such considerations as fiber-matrix reactions, diffusion bonding, and electromigration in interconnects in electronic devices, while solid-liquid interactions have practical significance in liquid metal infiltration, soldering and brazing, liquid-metal coating, and liquid metal corrosion. Related to the latter are investigations on solidification and the effect of various parameters on the resulting microstructure. One parameter of interest to the present investigation relates to the effect of electric fields. It was found that the electric field played a dominant role in the dynamics of these reactions and in the concomitant phase formation and microstructure evolution. Due to the difficulty in decoupling the large effect of Joule heating from other current effects, the role of the current is not fully understood. Electromigration is perhaps the best-known electric current effect on conductors. However, the nature of the role of the field in these processes could not be unambiguously determined. In this research, the electric field effect on two simple systems: solid Ni/liquid Al and solid Cu/Ni, was investigated. In solid Ni/liquid Al case, the current effects on the dissolution kinetics of solid Ni into liquid Al, and on the microstructure of solidified samples were investigated. The current had a marked effect on the dissolution rate constant. Correspondingly, the application of the current decreased the activation energy of dissolution significantly. The direction of the DC current was shown to have an effect on dissolution. The influence of a DC current on the microstructural evolution of phases resulting from the dissolution of solid nickel in pure and Ni-saturated liquid aluminum was investigated. In solid Cu/Ni case, the effect of a DC current on the interdiffusivity, D˜, was investigated. Interdiffusivities were calculated using the Sauer-Freise-den Broeder (SFB) method and the values calculated in the absence of a current were in agreement with previously published results. The influence of the current on D˜ depended on its direction relative to the two interfaces in the tri-layered Cu-Ni-Cu samples.

  2. Numerical simulation of solid liquid interface behavior during continuous strip casting process.

    PubMed

    Lee, Changbum; Yoon, Wooyoung; Shin, Seungwon; Lee, Jaewoo; Jang, Bo-Yun; Kim, Joonsoo; Ahn, Youngsoo; Lee, Jinseok

    2013-05-01

    A new metal-strip-casting process called continuous strip-casting (CSC) has been developed for making thin metal strips. A numerical simulation model to help understand solid-liquid interface behavior during CSC has been developed and used to identify the solidification morphologies of the strips and to determine the optimum processing conditions. In this study, we used a modified level contour reconstruction method (LCRM) and the sharp interface method to modify interface tracking, and performed a simulation analysis of the CSC process. The effects of process parameters such as heat-transfer coefficient and extrusion velocity on the behavior of the solid-liquid interface were estimated and used to improve the apparatus. A Sn (Tin) plate of dimensions 200 x 50 x 1 mm3 was successfully produced by CSC for a heat-transfer coefficient of 104 W/m2 K and an extrusion velocity of 0.2 m/s. PMID:23858856

  3. A hybrid anaerobic solid-liquid bioreactor for food waste digestion

    Microsoft Academic Search

    Xu Hai-Lou; Wang Jing-Yuan; Tay Joo-Hwa

    2002-01-01

    A hybrid anaerobic solid-liquid (HASL) bioreactor is an enhanced two-phase anaerobic system, that consists of a solid waste reactor as the acidification reactor and a wastewater reactor, i.e. an upflow anaerobic sludge blanket (UASB) reactor as the methanogenic reactor. Food waste digestion in HASL bioreactors with pre-acidification and HASL operation stages was investigated in two separate runs. After 8 days

  4. Experimental study of solid–liquid phase change in a spiral thermal energy storage unit

    Microsoft Academic Search

    J Banaszek; R Domañski; M Rebow; F El-Sagier

    1999-01-01

    A new idea on the use of a vertical spiral heat exchanger in a latent heat thermal energy storage system is analyzed experimentally. In this context, two important subjects are addressed. The first one is the temporal behavior of a phase change medium undergoing a non-isothermal solid–liquid phase change transition during its two-side heating or cooling by a working fluid

  5. Electrokinetic microslit experiments to analyse the charge formation at solid\\/liquid interfaces

    Microsoft Academic Search

    Ralf Zimmermann; Toshihisa Osaki; Rüdiger Schweiß; Carsten Werner

    2006-01-01

    Electrokinetic effects play an important role in microfluidics and nanofluidics. Although the related phenomena are often utilized to control fluid flow and sample transport in lab-on-a-chip devices, their dependency on the surface charges on the channel walls often remain enigmatic. This is mainly due to the lack of adequate experimental methods to analyse the electrical charging of solid\\/liquid interfaces of

  6. Note: Sample cells to investigate solid/liquid interfaces with neutrons.

    PubMed

    Rennie, Adrian R; Hellsing, Maja S; Lindholm, Eric; Olsson, Anders

    2015-01-01

    The design of sample cells to study solid/liquid interfaces by neutron reflection is presented. Use of standardized components and a modular design has allowed a wide range of experiments that include grazing incidence scattering and conventional small-angle scattering. Features that reduce background scattering are emphasized. Various flow arrangements to fill and replenish the liquid in the cell as well as continuous stirring are described. PMID:25638142

  7. Solid-liquid phase diagrams for binary metallic alloys: Adjustable interatomic potentials

    Microsoft Academic Search

    H.-S. Nam; M. I. Mendelev; D. J. Srolovitz

    2007-01-01

    We develop an approach to determining Lennard-Jones embedded-atom method potentials for alloys and use these to determine the solid-liquid phase diagrams for binary metallic alloys using Kofke's Gibbs-Duhem integration technique combined with semigrand canonical Monte Carlo simulations. We demonstrate that it is possible to produce a wide range of experimentally observed binary phase diagrams (with no intermetallic phases) by reference

  8. Solid-liquid phase diagrams for binary metallic alloys: Adjustable interatomic potentials

    Microsoft Academic Search

    H.-S. Nam; M. I. Mendelev; D. J. Srolovitz

    2007-01-01

    We develop a new approach to determining LJ-EAM potentials for alloys and use\\u000athese to determine the solid-liquid phase diagrams for binary metallic alloys\\u000ausing Kofke's Gibbs-Duhem integration technique combined with semigrand\\u000acanonical Monte Carlo simulations. We demonstrate that it is possible to\\u000aproduce a wide-range of experimentally observed binary phase diagrams (with no\\u000aintermetallic phases) by reference to the

  9. Solid-liquid phase equilibria of benzene + 2-methyl-2-propanol system under high pressures

    Microsoft Academic Search

    K. Nagaoka; T. Makita

    1988-01-01

    Solid-liquid phase equilibria of the benzene + 2-methyl-2-propanol system have been investigated at temperatures from 278 to 323 K and pressures up to 300 MPa using a high-pressure optical vessel. The uncertainties of the measurements of temperature, pressure and composition are within ±0.1 K, ±0.5 MPa, and ±0.001 mole fraction, respectively. The freezing pressure at a constant composition increases monotonously

  10. Understanding the lateral movement of particles adsorbed at a solid-liquid interface.

    PubMed

    Savaji, Kunal; Li, Xue; Couzis, Alexander

    2015-09-01

    In this paper we study the phenomenon of lateral movement of particles that are electrostatically adsorbed at a solid-liquid interface. The experimental system involves negatively charged silica particles of two different sizes (65nm and 90nm) that are exposed to the positively charged solid surface (silane coated silicon wafer) in sequential steps. The particle-adsorbed wafers are analyzed under a scanning electron microscope and the images are processed to determine the pair-correlation function for the particles adsorbed in the first step. From the pair correlation data and the particle surface coverage data we show that the adsorbed particles are mobile at the solid-liquid interface. In specific, we show that the adsorbed particles are mobile at the solid-liquid interface when there is a driving force for the adsorbed particles to move. The driving force in the scheme of experiments discussed in this paper is the reduction in the free energy of the system. PMID:26005924

  11. Abrasion characteristic analyses of solid-liquid two-phase centrifugal pump

    NASA Astrophysics Data System (ADS)

    Li, Yi; Zhu, Zuchao; He, Zhaohui; He, Weiqiang

    2011-09-01

    Based on the solid-liquid two-phase mixture transportation test, the renormalization group (RNG) k-e turbulent model was utilized to simulate the solid-liquid two-phase turbulent flow in a centrifugal pump. By comparing the simulated and experimental results, inner flow features were revealed to improve the abrasion characteristic of the solid-liquid two-phase centrifugal pump. The influence of the solid phase on centrifugal pump abrasive performance is small when the particle volume fraction is less than 2.5%. The aggregation degree of the solid particles is enhanced as the particle diameter increases from 0.1 to 1 mm; however, the mixture density on the pressure side is reduced when the particle diameter increases to 1 mm for the impact of inertia. The wear on the hub is most severe for the shear stress on this position; it is also the largest. The wear characteristic is affected greatly by the parameters of the solid phase. The wear chracteristic can be optimized by decreasing the blade outlet angle. In the modified design, the blade angle is different, whereas the other geometric dimensions remain the same. The improved pump is simulated to contrast with the original pump. The results show that the values of mixture density and shear stress both decrease. The wear condition of the blade is improved to a certain extent.

  12. Direct numerical simulation of solid-liquid flow of Newtonian and viscoelastic fluids

    NASA Astrophysics Data System (ADS)

    Zhu, Mingyu

    The main theme of this work is to enhance the understanding on the behavior of solid particles in flows of Newtonian or viscoelastic fluids by using both two-dimensional and three-dimensional direct numerical simulations (DNS). A large-scale state-of-the-art software package PARTMOVER3D is developed based on an Arbitrary Lagrangian-Eulerian (ALE) technique and an Elastic-Viscous-Stress-Split (EVSS) scheme. Our numerical results are extensively compared with analytical, experimental and numerical ones in the literature. We studied the motion of spheres sedimenting in a cylindrical tube filled with a Newtonian fluid. The hydrodynamic drag and lift on the particle are investigated under various conditions. The effects of the tube wall, in terms of the blockage ratio and the eccentricity ratio, on the particle terminal velocity, migration and rotation are studied. We also investigated the interaction between pair particles released in tandem or side by side at different Reynolds numbers. The migration of particles in a pressure driven flow is the heart of vast number of industrial applications. Using 3-D direct numerical simulations, we systematically investigated the independent parameters controlling the particle migration, which are the blockage ratio, the flow Reynolds number, and the solid-liquid density ratio. During the particle migration, the mechanisms of the fluid inertia, the wall confinement, the local flow shear rate, the particle slip velocity, the particle size, and the particle rotation were extensively examined through the stress distribution on the particle surface under different flow conditions. In the presence of a shear flow, an initially deposited bed of heavy particles will be entrained into the bulk fluid and convected away with the flow. We investigated the mechanism of this particle resuspension by using 2-D direct numerical simulations. Various effects on the lift force on the particle was analyzed by examining the distribution of the stress on the particle surface. We also studied the orientation of an elliptic particle during its resuspension, analyzed the interaction between a pair of particles, and presented the results of the resuspension of a layer of particles. There are striking differences of particle motions in viscoelastic and Newtonian fluids. We explained the mechanism of the anomalous particle behavior due to the elasticity of the viscoelastic fluid. The effects of the Deborah number, the Reynolds number, the retardation-relaxation time ratio, the blockage ratio, and the eccentricity rate on the behavior of the particles were also systemically investigated.

  13. Flow Strength of Shocked Aluminum in the Solid-Liquid Mixed Phase Region

    NASA Astrophysics Data System (ADS)

    Reinhart, William

    2011-06-01

    Shock waves have been used to determine material properties under high shock stresses and very-high loading rates. The determination of mechanical properties such as compressive strength under shock compression has proven to be difficult and estimates of strength have been limited to approximately 100 GPa or less in aluminum. The term ``strength'' has been used in different ways. For a Von-Mises solid, the yield strength is equal to twice the shear strength of the material and represents the maximum shear stress that can be supported before yield. Many of these concepts have been applied to materials that undergo high strain-rate dynamic deformation, as in uni-axial strain shock experiments. In shock experiments, it has been observed that the shear stress in the shocked state is not equal to the shear strength, as evidenced by elastic recompressions in reshock experiments. This has led to an assumption that there is a yield surface with maximum (loading)and minimum (unloading), shear strength yet the actual shear stress lies somewhere between these values. This work provides the first simultaneous measurements of unloading velocity and flow strength for transition of solid aluminum to the liquid phase. The investigation describes the flow strength observed in 1100 (pure), 6061-T6, and 2024 aluminum in the solid-liquid mixed phase region. Reloading and unloading techniques were utilized to provide independent data on the two unknowns (?c and ?o) , so that the actual critical shear strength and the shear stress at the shock state could be estimated. Three different observations indicate a change in material response for stresses of 100 to 160 GPa; 1) release wave speed (reloading where applicable) measurements, 2) yield strength measurements, and 3) estimates of Poisson's ratio, all of which provide information on the melt process including internal consistency and/or non-equilibrium and rate-dependent melt behavior. The study investigates the strength properties in the solid region and as the material transverses the solid-mixed-liquid regime. Differences observed appear to be the product of alloying and/or microstructural composition of the aluminum. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000.

  14. Determination of the solid-liquid interfacial free energy along a coexistence line by Gibbs–Cahn integration

    E-print Network

    Laird, Brian Bostian; Davidchack, Ruslan L.; Yang, Yang; Asta, Mark

    2009-09-18

    We calculate the solid-liquid interfacial free energy?sl for the Lennard-Jones (LJ) system at several points along the pressure-temperature coexistence curve using molecular-dynamics simulation and Gibbs–Cahn integration. ...

  15. Preparation and performance of form-stable polyethylene glycol\\/silicon dioxide composites as solid–liquid phase change materials

    Microsoft Academic Search

    Weilong Wang; Xiaoxi Yang; Yutang Fang; Jing Ding

    2009-01-01

    This work mainly involved the preparation and characterization of form-stable polyethylene glycol (PEG)\\/silicon dioxide (SiO2) composite as a novel solid–liquid phase change material (PCM). In this study, the polyethylene glycol\\/silicon dioxide composites as form-stable, solid–liquid phase change material (PCM) was prepared. In this new material, the polyethylene glycol acts as the latent heat storage material and silicon dioxide serves as

  16. Solid–liquid equilibria of closely boiling compounds of 4-methoxyphenol and catechol with p-cresol

    Microsoft Academic Search

    Ho-mu Lin; Yu-Hsing Chou; Fu-Li Wu; Ming-Jer Lee

    2004-01-01

    Solid–liquid equilibrium data were measured for binary and ternary mixtures composed of p-cresol with closely boiling compounds: 4-methoxyphenol and catechol. Experimental results revealed that all the binaries behave as simple eutectic systems. The eutectic loci were also observed for the mixtures of 4-methoxyphenol+catechol+p-cresol, from which a ternary solid–liquid equilibrium phase diagram was obtained. The Wilson and the NRTL models were

  17. Numerical simulation and analysis of solid-liquid two-phase flow in centrifugal pump

    NASA Astrophysics Data System (ADS)

    Zhang, Yuliang; Li, Yi; Cui, Baoling; Zhu, Zuchao; Dou, Huashu

    2013-01-01

    The flow with solid-liquid two-phase media inside centrifugal pumps is very complicated and the relevant method for the hydraulic design is still immature so far. There exist two main problems in the operation of the two-phase flow pumps, i.e., low overall efficiency and severe abrasion. In this study, the three-dimensional, steady, incompressible, and turbulent solid-liquid two-phase flows in a low-specific-speed centrifugal pump are numerically simulated and analyzed by using a computational fluid dynamics (CFD) code based on the mixture model of the two-phase flow and the RNG k- ? two-equation turbulence model, in which the influences of rotation and curvature are fully taken into account. The coupling between impeller and volute is implemented by means of the frozen rotor method. The simulation results predicted indicate that the solid phase properties in two-phase flow, especially the concentration, the particle diameter and the density, have strong effects on the hydraulic performance of the pump. Both the pump head and the efficiency are reduced with increasing particle diameter or concentration. However, the effect of particle density on the performance is relatively minor. An obvious jet-wake flow structure is presented near the volute tongue and becomes more remarkable with increasing solid phase concentration. The suction side of the blade is subject to much more severe abrasion than the pressure side. The obtained results preliminarily reveal the characteristics of solid-liquid two-phase flow in the centrifugal pump, and are helpful for improvement and empirical correction in the hydraulic design of centrifugal pumps.

  18. Detection of Gold Colloid Adsorption at a Solid/Liquid Interface Using Micromachined Piezoelectric Resonators

    NASA Astrophysics Data System (ADS)

    Guirardel, Matthieu; Nicu, Liviu; Saya, Daisuke; Tauran, Yannick; Cattan, Eric; Remiens, Denis; Bergaud, Christian

    2004-01-01

    Microfabricated piezoelectric resonators have been used in a liquid environment for real time detection of gold colloid adsorption at a solid/liquid interface. Negatively charged gold colloids in suspension in a buffer solution adsorb on the surface of the piezoelectric microresonator passivated with a silicon dioxide layer that has been functionalized with an amino-silane self-assembled monolayer. The mass loading induced by adsorption on the surface of the piezoelectric resonator leads to a change in resonant frequency. Measured frequency shift as a function of time incubation in a colloidal suspension was observed and correlated with the mass of adsorbed gold colloids.

  19. Quantitative Measurements of Adsorbate-Adsorbate Interactions at Solid-Liquid Interfaces

    NASA Astrophysics Data System (ADS)

    Taranovskyy, A.; Tansel, T.; Magnussen, O. M.

    2010-03-01

    The interactions between adsorbates at a solid-liquid interface were studied by video-rate STM for the case of sulfur on Cu(100) electrode surfaces in HCl solution. Quantitative data were obtained by analyzing the Sad dimer dynamics within the surrounding c(2×2)-Cl adlattice as well as the adsorbate configurations. The interactions are repulsive for Sad separated by one or two lattice spacings and attractive at a separation of 2 with energies comparable to adsorbates at the solid-vacuum interface. The Sad diffusion barriers are significantly reduced in the vicinity of a neighboring adsorbate.

  20. Surface-induced selection during in?situ photoswitching at the solid/liquid interface.

    PubMed

    Bonacchi, Sara; El Garah, Mohamed; Ciesielski, Artur; Herder, Martin; Conti, Simone; Cecchini, Marco; Hecht, Stefan; Samorì, Paolo

    2015-04-13

    Here we report for the first time a submolecularly resolved scanning tunneling microscopy (STM) study at the solid/liquid interface of the in?situ reversible interconversion between two isomers of a diarylethene photoswitch, that is, open and closed form, self-assembled on a graphite surface. Prolonged irradiation with UV light led to the in?situ irreversible formation of another isomer as by-product of the reaction, which due to its preferential physisorption accumulates at the surface. By making use of a simple yet powerful thermodynamic model we provide a quantitative description for the observed surface-induced selection of one isomeric form. PMID:25728405

  1. Structural Evolution of Silicon Oxide Nanowires via Head-Growth Solid-Liquid-Solid Process

    NASA Astrophysics Data System (ADS)

    Hsu, Cheng-Hang; Chan, Shih-Yu; Chen, Chia-Fu

    2007-11-01

    In this paper, we propose a growth mechanism for silicon oxide nanowires (SiONWs) as a unique solid-liquid-solid process. SiONWs were synthesized in a furnace at 1000 °C and cooled at a high rate. Nickel and gold were introduced as catalysts to dissolve and precipitate the silicon oxide originally prepared by wet oxidation. The ratio of nickel to gold determined the precipitation rate and different “octopus-like” structures were formed. At a specific cooling rate, composition and amount of a catalyst, aligned silicon oxide nanowires with unattached ends were obtained.

  2. Its Just a Phase: Water as a Solid, Liquid, and Gas

    NSDL National Science Digital Library

    In this lesson, students will construct models of the way water molecules arrange themselves in the three physical states. They will come to understand that matter can be found in three forms or phases (solid, liquid, and gas). Using physical models, students will be able to explain the molecular behavior of ice, water, and water vapor. The instructor guide contains detailed background material, learning goals, alignment to national standards, grade level/time, details on materials and preparation, procedure, assessment ideas, and modifications for alternative learners.

  3. The discrete multi-hybrid system for the simulation of solid-liquid flows.

    PubMed

    Alexiadis, Alessio

    2015-01-01

    This study proposes a model based on the combination of Smoothed Particle Hydrodynamics, Coarse Grained Molecular Dynamics and the Discrete Element Method for the simulation of dispersed solid-liquid flows. The model can deal with a large variety of particle types (non-spherical, elastic, breakable, melting, solidifying, swelling), flow conditions (confined, free-surface, microscopic), and scales (from microns to meters). Various examples, ranging from biological fluids to lava flows, are simulated and discussed. In all cases, the model captures the most important features of the flow. PMID:25961561

  4. On-farm treatment of swine manure based on solid-liquid separation and biological nitrification-denitrification of the liquid fraction.

    PubMed

    Riaño, B; García-González, M C

    2014-01-01

    In some regions, intensive pig farming has led to soil and water pollution due to the over-application of manure as an organic fertilizer, thereby necessitating alternative treatment technologies to help manage the large amounts of manure generated. The present study seeks to determine the effectiveness of an on-farm swine manure treatment plant consisting of a solid-liquid separation phase using screw pressing followed by a coagulation-flocculation process, and nitrification-denitrification of the liquid fraction. Each treatment unit was evaluated for its contribution towards reducing the raw manure concentration of solids, organic matter, nutrients (nitrogen and phosphorous), metals, and pathogens. The overall system presented high removal efficiencies of up to 71% of TS (total solids) and 97% of TCOD (total chemical oxygen demand). Approximately 97% TKN (total Kjeldahl nitrogen) and 89% TP (total phosphorous) removal was achieved. Metals (copper and zinc) diminished in the liquid fraction to non-detectable concentrations (<1.0 mg L(-1)). As regards microbial removal, total concentration reductions of 3.6 log10 for Escherichia coli and 1.8 log10 for Salmonella were achieved. Finally, the system was evaluated from a financial standpoint. Results indicate that screw pressing and coagulation-flocculation for solid-liquid separation and nitrification-denitrification of the liquid fraction is a technological alternative for reducing the environmental impact of intensive pig farming in a given area. PMID:24291581

  5. Nanocrystallization of CaCO 3 at solid/liquid interfaces in magnetic field: A quantum approach

    NASA Astrophysics Data System (ADS)

    Cefalas, A. C.; Kobe, S.; Dražic, G.; Sarantopoulou, E.; Kollia, Z.; Stražišar, J.; Meden, A.

    2008-08-01

    With the application of 1.2 T external magnetic field, 90% of CaCO 3 soluble molecules in water flow precipitate on stainless steel 316 solid/liquid interface in the form of aragonite/vaterite. The magnetic field increases locally the thermodynamic potentials at interface, favoring the formation of aragonite than calcite, despite the fact that the field-free ground electronic state of aragonite is situated higher than of calcite. A quantum mechanical model predicts that magnetic fluctuations inside the liquid can be amplified by exchanging energy with an external magnetic field through the angular momentum of the water molecular rotors and with the macroscopic angular momentum of the turbulent flow. The theoretical model predicts that the gain is higher when the magnetic field is in resonance with the rotational frequencies of the molecular rotors or/and the low frequencies of the turbulent flow and that aragonite concentration is increasing at 0.4 T in agreement with the experimental results. Contrary to calcite, aragonite binds weakly on flow surfaces; and hence the process has significant industrial, environmental and biological impact.

  6. Computer simulation of solid-liquid coexistence in binary hard sphere mixtures

    NASA Astrophysics Data System (ADS)

    Kranendonk, W. G. T.; Frenkel, D.

    We present the results of a computer simulation study of the solid-liquid coexistence of a binary hard sphere mixture for diameter ratios in the range 0·85 ? ?a ? 1>·00. For the solid phase we only consider substitutionally disordered FCC and HCP crystals. For 0·9425 < ? < 1·00 we find a solid-liquid coexistence curve of the 'spindle' type. For ? = 0·9425 this becomes an azeotropic and for ? = 0·875 a eutectic diagram. We compare these results with the predictions of the density functional theory of Barrat, Baus and Hansen. We observe that the density functional theory accurately predicts the point where the spindle diagram transforms into an azeotrope. However, the density functional theory differs from the simulation results on a number of counts. The greatest differences between computer simulations and theory are that the changeover from an azeotropic to a eutectic diagram is found to occur at ? = 0·875, rather than at the predicted value of ? = 0·92, that the density difference between the solid and the liquid at liquid-solid coexistence is found to have a minimum as a function of the mole fraction of the large spheres, while density functional theory predicts a maximum, and finally that the solubility of large spheres in a solid mixture of small spheres is much larger than predicted.

  7. Investigating the solid-liquid phase transition of water nanofilms using the generalized replica exchange method

    SciTech Connect

    Lu, Qing [Division of Materials Science and Engineering, Boston University, Brookline, Massachusetts 02446 (United States); Kim, Jaegil; Straub, John E., E-mail: straub@bu.edu [Department of Chemistry, Boston University, Boston, Massachusetts 02215 (United States); Farrell, James D.; Wales, David J. [University Chemical Laboratories, Lensfield Road, Cambridge CB2 1EW (United Kingdom)

    2014-11-14

    The generalized Replica Exchange Method (gREM) was applied to study a solid-liquid phase transition in a nanoconfined bilayer water system using the monatomic water (mW) model. Exploiting optimally designed non-Boltzmann sampling weights with replica exchanges, gREM enables an effective sampling of configurations that are metastable or unstable in the canonical ensemble via successive unimodal energy distributions across phase transition regions, often characterized by S-loop or backbending in the statistical temperature. Extensive gREM simulations combined with Statistical Temperature Weighted Histogram Analysis Method (ST-WHAM) for nanoconfined mW water at various densities provide a comprehensive characterization of diverse thermodynamic and structural properties intrinsic to phase transitions. Graph representation of minimized structures of bilayer water systems determined by the basin-hopping global optimization revealed heterogeneous ice structures composed of pentagons, hexagons, and heptagons, consistent with an increasingly ordered solid phase with decreasing density. Apparent crossover from a first-order solid-liquid transition to a continuous one in nanoconfined mW water with increasing density of the system was observed in terms of a diminishing S-loop in the statistical temperature, smooth variation of internal energies and heat capacities, and a characteristic variation of lateral radial distribution functions, and transverse density profiles across transition regions.

  8. Nanoelectrical analysis of single molecules and atomic-scale materials at the solid/liquid interface.

    PubMed

    Nirmalraj, Peter; Thompson, Damien; Molina-Ontoria, Agustín; Sousa, Marilyne; Martín, Nazario; Gotsmann, Bernd; Riel, Heike

    2014-10-01

    Evaluating the built-in functionality of nanomaterials under practical conditions is central for their proposed integration as active components in next-generation electronics. Low-dimensional materials from single atoms to molecules have been consistently resolved and manipulated under ultrahigh vacuum at low temperatures. At room temperature, atomic-scale imaging has also been performed by probing materials at the solid/liquid interface. We exploit this electrical interface to develop a robust electronic decoupling platform that provides precise information on molecular energy levels recorded using in situ scanning tunnelling microscopy/spectroscopy with high spatial and energy resolution in a high-density liquid environment. Our experimental findings, supported by ab initio electronic structure calculations and atomic-scale molecular dynamics simulations, reveal direct mapping of single-molecule structure and resonance states at the solid/liquid interface. We further extend this approach to resolve the electronic structure of graphene monolayers at atomic length scales under standard room-temperature operating conditions. PMID:25129620

  9. Coarsening in Solid-Liquid Mixtures Studied on the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Caruso, John J.

    1999-01-01

    Ostwald ripening, or coarsening, is a process in which large particles in a two-phase mixture grow at the expense of small particles. It is a ubiquitous natural phenomena occurring in the late stages of virtually all phase separation processes. In addition, a large number of commercially important alloys undergo coarsening because they are composed of particles embedded in a matrix. Many of them, such as high-temperature superalloys used for turbine blade materials and low-temperature aluminum alloys, coarsen in the solid state. In addition, many alloys, such as the tungsten-heavy metal systems, coarsen in the solid-liquid state during liquid phase sintering. Numerous theories have been proposed that predict the rate at which the coarsening process occurs and the shape of the particle size distribution. Unfortunately, these theories have never been tested using a system that satisfies all the assumptions of the theory. In an effort to test these theories, NASA studied the coarsening process in a solid-liquid mixture composed of solid tin particles in a liquid lead-tin matrix. On Earth, the solid tin particles float to the surface of the sample, like ice in water. In contrast, in a microgravity environment this does not occur. The microstructures in the ground- and space-processed samples (see the photos) show clearly the effects of gravity on the coarsening process. The STS-83-processed sample (right image) shows nearly spherical uniformly dispersed solid tin particles. In contrast, the identically processed, ground-based sample (left image) shows significant density-driven, nonspherical particles, and because of the higher effective solid volume fraction, a larger particle size after the same coarsening time. The "Coarsening in Solid-Liquid Mixtures" (CSLM) experiment was conducted in the Middeck Glovebox facility (MGBX) flown aboard the shuttle in the Microgravity Science Laboratory (MSL-1/1R) on STS-83/94. The primary objective of CSLM is to measure the temporal evolution of the solid particles during coarsening.

  10. New Composite Membranes for High Throughput Solid-Liquid Separations at the Savannah River Site

    SciTech Connect

    Bhave, Ramesh R [ORNL

    2012-01-01

    New Composite Membranes for High Throughput Solid-Liquid Separations at the Savannah River Site R. Bhave (Oak Ridge National Laboratory. Oak Ridge, TN) and M. R. Poirier* (Savannah River National Laboratory, Aiken SC) Solid-liquid separation is the limiting step for many waste treatment processes at the Savannah River Site. SRNL researchers have identified the rotary microfilter as a technology to improve the rate of solid-liquid separation processes. SRNL is currently developing the rotary microfilter for radioactive service and plans to deploy the technology as part of the small column ion exchange process. The rotary microfilter can utilize any filter media that is available as a flat sheet. The current baseline membrane is a 0.5 micron (nominal) porous metal filter (Pall PMM050). Previous testing with tubular filters showed that filters composed of a ceramic membrane on top of a stainless steel support produce higher flux than filters composed only of porous metal. The authors are working to develop flat sheet filter media composed of a ceramic membrane and/or ceramic-metal composite on top of a porous stainless steel support that can be used with the rotary microfilter to substantially increase filter flux resulting in a more compact, energy efficient and cost-effective high level radioactive waste treatment system. Composite membranes with precisely controlled pore size distribution were fabricated on porous metal supports. High quality uniform porous metal (316SS) supports were fabricated to achieve high water permeability. Separative layers of several different materials such as ultrafine metal particles and ceramic oxides were used to fabricate composite membranes. The fabrication process involved several high temperature heat treatments followed by characterization of gas and liquid permeability measurements and membrane integrity analysis. The fabricated composite membrane samples were evaluated in a static test cell manufactured by SpinTek. The composite membranes were evaluated on several feed slurries: 1 wt. % strontium carbonate in deionized water, 1 wt. % monosodium titanate in simulated salt solution, and 1 wt. % simulated sludge in simulated salt solution and deionized water. Flux as a function of feed flow rate and transmembrane pressure was measured for each of the above described feed slurries. The authors will discuss the new membrane development efforts, waste slurry filtration performance evaluations and scale-up considerations.

  11. Molecular Dynamics Simulation of Argon in Solid-Liquid Phase Transition Region

    NASA Astrophysics Data System (ADS)

    Özgen, Soner; Kuzucu, Veysel; Adigüzel, Osman

    1997-10-01

    The microstructure of 256 argon atoms located on ideal fcc lattice sites on which periodic boundary conditions have been applied at the vicinity of transition temperature has been investigated. The forces among atoms have been derived from Lennard-Jones potential energy function and the equations of motion of the system have been solved by using the Verlet algorithm. The variations in microstructure have been investigated by means of radial distribution function and real-space atomic trajectories. It has been found from the results of simulation at zero pressure that solid-liquid transition temperature is 86K, the change of enthalpy is 1202 J/mol and relative volume change is 0.14.

  12. A low-cost solid-liquid separation process for enzymatically hydrolyzed corn stover slurries.

    PubMed

    Sievers, David A; Lischeske, James J; Biddy, Mary J; Stickel, Jonathan J

    2015-07-01

    Solid-liquid separation of intermediate process slurries is required in some process configurations for the conversion of lignocellulosic biomass to transportation fuels. Thermochemically pretreated and enzymatically hydrolyzed corn stover slurries have proven difficult to filter due to formation of very low permeability cakes that are rich in lignin. Treatment of two different slurries with polyelectrolyte flocculant was demonstrated to increase mean particle size and filterability. Filtration flux was greatly improved, and thus scaled filter unit capacity was increased approximately 40-fold compared with unflocculated slurry. Although additional costs were accrued using polyelectrolyte, techno-economic analysis revealed that the increase in filter capacity significantly reduced overall production costs. Fuel production cost at 95% sugar recovery was reduced by $1.35 US per gallon gasoline equivalent for dilute-acid pretreated and enzymatically hydrolyzed slurries and $3.40 for slurries produced using an additional alkaline de-acetylation preprocessing step that is even more difficult to natively filter. PMID:25836372

  13. Behavior of polyethylene glycol molecules at an oscillating solid-liquid interface.

    PubMed

    Yoshimoto, Minoru; Yuda, Yukiko; Tanaka, Mutsuo; Kurosawa, Shigeru

    2014-01-01

    The behavior of polyethylene glycol (PEG) molecules at an oscillating solid-liquid interface was examined using a quartz crystal microbalance (QCM). The number-average molecular weights (Mn) of PEG molecules were systematically varied. This study revealed that the shift in the energy dissipation factor, ?D, of the QCM against square root of the density-viscosity product of the PEG solution is linear and has an intercept. Moreover, the systematical analysis revealed that the ?D slope rapidly decreases with Mn, and the ?D intercept becomes constant above 1.1×10(4) g/mol. Those results indicated that the resonant length of PEG molecules moving with the oscillating plate at 9 MHz is 97.6 Å. We also found that the difference between the resonant lengths calculated from ?D and series resonance-frequency shift, ?F, is related to the density of the thin PEG layer formed on the gold electrode. PMID:24389797

  14. Effects of Solid-Liquid Mixing on Microstructure of Semi-Solid A356 Aluminum Alloy

    NASA Astrophysics Data System (ADS)

    Guo, H. M.; Wang, L. J.; Wang, Q.; Yang, X. J.

    2014-08-01

    The desired starting material for semi-solid processing is the semi-solid slurry in which the solid phase is present as fine and globular particles. A modified solid-liquid mixing (SLM) is reported wherein semi-solid slurry can be produced by mixing a solid alloy block into a liquid alloy, and mechanical vibration is utilized to enhance the mixing. Effects such as liquid alloy temperature, mass ratio, and mixing intensity on the microstructure and the cooling curves during SLM were evaluated. 2D and 3D microstructure analysis of treated A356 aluminum alloy shows that microstructure can be refined significantly with a considerable morphology change in primary Al phase. It is critical that the temperature of mixture after mixing is lower than its liquidus temperature to obtain a valid SLM process. Specially, mixing intensity is identified as a primary factor for a favorable microstructure of semi-solid slurry.

  15. Surface Specularity as an Indicator of Shock-induced Solid-liquid Phase Transitions in Tin

    SciTech Connect

    G. D. Stevens, S. S. Lutz, B. R. Marshall, W.D. Turley, et al.

    2007-12-01

    When highly polished metal surfaces melt upon release after shock loading, they exhibit features that suggest significant surface changes accompany the phase transition. The reflection of light from such surfaces changes from specular (pre-shock) to diffuse upon melting. Typical of this phenomenon is the loss of signal light in velocity interferometer system for any reflector (VISAR) measurements, which usually occurs at pressures high enough to melt the free surface. Unlike many other potential material phase-sensitive diagnostics (e.g., reflectometry, conductivity), that show relatively small (1%-10%) changes, the specularity of reflection provides a more sensitive and definitive (>10x) indication of the solid-liquid phase transition. Data will be presented that support the hypothesis that specularity changes indicate melt in a way that can be measured easily and unambiguously.

  16. Modeling of ultrasound transmission through a solid-liquid interface comprising a network of gas pockets

    SciTech Connect

    Paumel, K.; Baque, F. [CEA, DEN, Nuclear Technology Department, F-13108 Saint-Paul-lez-Durance (France); Moysan, J.; Corneloup, G. [Laboratoire de Caracterisation Non Destructive, Universite de la Mediterranee, IUT Aix-en-Provence, Avenue Gaston Berger, 13625 Aix-en-Provence (France); Chatain, D. [CNRS, Aix-Marseille Universite, CINAM-UPR3118, Campus de Luminy, Case 913, 13288 Marseille cedex 09 (France)

    2011-08-15

    Ultrasonic inspection of sodium-cooled fast reactor requires a good acoustic coupling between the transducer and the liquid sodium. Ultrasonic transmission through a solid surface in contact with liquid sodium can be complex due to the presence of microscopic gas pockets entrapped by the surface roughness. Experiments are run using substrates with controlled roughness consisting of a network of holes and a modeling approach is then developed. In this model, a gas pocket stiffness at a partially solid-liquid interface is defined. This stiffness is then used to calculate the transmission coefficient of ultrasound at the entire interface. The gas pocket stiffness has a static, as well as an inertial component, which depends on the ultrasonic frequency and the radiative mass.

  17. Solid/Liquid phase diagram of the ammonium sulfate/succinic acid/water system.

    PubMed

    Pearson, Christian S; Beyer, Keith D

    2015-05-14

    We have studied the low-temperature phase diagram and water activities of the ammonium sulfate/succinic acid/water system using differential scanning calorimetry and infrared spectroscopy of thin films. Using the results from our experiments, we have mapped the solid/liquid ternary phase diagram, determined the water activities based on the freezing point depression, and determined the ice/succinic acid phase boundary as well as the ternary eutectic composition and temperature. We also compared our results to the predictions of the extended AIM aerosol thermodynamics model (E-AIM) and found good agreement for the ice melting points in the ice primary phase field of this system; however, differences were found with respect to succinic acid solubility temperatures. We also compared the results of this study with those of previous studies that we have published on ammonium sulfate/dicarboxylic acid/water systems. PMID:25431860

  18. Bilayer molecular assembly at a solid/liquid interface as triggered by a mild electric field.

    PubMed

    Zheng, Qing-Na; Liu, Xuan-He; Liu, Xing-Rui; Chen, Ting; Yan, Hui-Juan; Zhong, Yu-Wu; Wang, Dong; Wan, Li-Jun

    2014-12-01

    The construction of a spatially defined assembly of molecular building blocks, especially in the vertical direction, presents a great challenge for surface molecular engineering. Herein, we demonstrate that an electric field applied between an STM tip and a substrate triggered the formation of a bilayer structure at the solid-liquid interface. In contrast to the typical high electric-field strength (10(9) ?V?m(-1) ) used to induce structural transitions in supramolecular assemblies, a mild electric field (10(5) ?V?m(-1) ) triggered the formation of a bilayer structure of a polar molecule on top of a nanoporous network of trimesic acid on graphite. The bilayer structure was transformed into a monolayer kagome structure by changing the polarity of the electric field. This tailored formation and large-scale phase transformation of a molecular assembly in the perpendicular dimension by a mild electric field opens perspectives for the manipulation of surface molecular nanoarchitectures. PMID:25376428

  19. Crystal growth from a supersaturated melt: relaxation of the solid-liquid dynamic stiffness

    E-print Network

    Francesco Turci; Tanja Schilling

    2014-05-20

    We discuss the growth process of a crystalline phase out of a metastable over-compressed liquid that is brought into contact with a crystalline substrate. The process is modeled by means of molecular dynamics. The particles interact via the Lennard-Jones potential and their motion is locally thermalized by Langevin dynamics. We characterize the relaxation process of the solid-liquid interface, showing that the growth speed is maximal for liquid densities above the solid coexistence density, and that the structural properties of the interface rapidly converge to equilibrium-like properties. In particular, we show that the off-equilibrium dynamic stiffness can be extracted using capillary wave theory arguments, even if the growth front moves fast compared to the typical diffusion time of the compressed liquid, and that the dynamic stiffness converges to the equilibrium stiffness in times much shorter than the diffusion time.

  20. Modeling of ultrasound transmission through a solid-liquid interface comprising a network of gas pockets

    NASA Astrophysics Data System (ADS)

    Paumel, K.; Moysan, J.; Chatain, D.; Corneloup, G.; Baqué, F.

    2011-08-01

    Ultrasonic inspection of sodium-cooled fast reactor requires a good acoustic coupling between the transducer and the liquid sodium. Ultrasonic transmission through a solid surface in contact with liquid sodium can be complex due to the presence of microscopic gas pockets entrapped by the surface roughness. Experiments are run using substrates with controlled roughness consisting of a network of holes and a modeling approach is then developed. In this model, a gas pocket stiffness at a partially solid-liquid interface is defined. This stiffness is then used to calculate the transmission coefficient of ultrasound at the entire interface. The gas pocket stiffness has a static, as well as an inertial component, which depends on the ultrasonic frequency and the radiative mass.

  1. Force response of actively deformed polymer microdroplets: dependence on the solid/liquid boundary condition

    NASA Astrophysics Data System (ADS)

    Heppe, Jonas; McGraw, Joshua D.; Bennewitz, Roland; Jacobs, Karin

    2015-03-01

    In fluid dynamics, the solid/liquid boundary condition can play a major role in the flow behavior of a liquid. For example, in the dewetting of identical polymer films on weak slip or strong slip substrates, large qualitative and quantitative differences are observed. Therefore, when applying an external load to a liquid resting on such substrates, the measured reaction forces and the ensuing flow should also depend on the boundary condition. We present atomic force microscopy measurements in which the reaction force of a cantilever is measured as the tip pierces liquid polymer micron sized droplets and films. These indentations are done on substrates with tuned slip. Accessing the size, depth and rate dependence of the resulting force distance curves, we show an influence of the slip condition on the dissipated energy and adhesion.

  2. Laboratory Production of Lemon Liqueur (Limoncello) by Conventional Maceration and a Two-Syringe System to Illustrate Rapid Solid-Liquid Dynamic Extraction

    ERIC Educational Resources Information Center

    Naviglio, Daniele; Montesano, Domenico; Gallo, Monica

    2015-01-01

    Two experimental techniques of solid-liquid extraction are compared relating to the lab-scale production of lemon liqueur, most commonly named "limoncello"; the first is the official method of maceration for the solid-liquid extraction of analytes and is widely used to extract active ingredients from a great variety of natural products;…

  3. Solid-Liquid Adsorption of Calcium Phosphate on TiO2 C. C. Chusuei and D. W. Goodman*

    E-print Network

    Goodman, Wayne

    Solid-Liquid Adsorption of Calcium Phosphate on TiO2 C. C. Chusuei and D. W. Goodman* Department of Chemistry, Texas A&M University, College Station, Texas 77843-3144 Received April 27, 1999 Calcium phosphate evidence for 3-dimensional (3D) phosphate islands forming on top of the calcium. ToF-SIMS analysis of CP

  4. Theoretical Studies of Solid-Liquid Interfaces: Molecular Interactions at the MgO(001)-Water Interface

    E-print Network

    Truong, Thanh N.

    Theoretical Studies of Solid-Liquid Interfaces: Molecular Interactions at the MgO(001)-Water chemistry are needed. A few quantum mechanical calculations concerning the properties of water and hydroxyl for Theoretical Chemistry, Department of Chemistry, UniVersity of Utah, Salt Lake City, Utah 84112 ReceiVed: March

  5. Chemical Engineering Science 55 (2000) 4993}5001 A further study of solid}liquid equilibrium for the

    E-print Network

    Zhang, Luzheng

    2000-01-01

    Chemical Engineering Science 55 (2000) 4993}5001 A further study of solid}liquid equilibrium Shi , Benjamin C. -Y. Lu Department of Chemical Engineering, Nanjing University of Chemical Technology, Nanjing 210009, People's Republic of China Department of Chemical Engineering, University of Ottawa

  6. Influence of ultrasound power on the alkylation of phenylacetonitrile under solid-liquid phase transfer catalysis conditions

    Microsoft Academic Search

    Richard Guilet; Jacques Berlan; Olivier Louisnard; Jacques Schwartzentruber

    1998-01-01

    The influence of ultrasound power on the C-alkylation of phenylacetonitrile by ethyl bromide was studied under solid-liquid phase transfer catalysis in the presence of potassium hydroxide and tetrabutylammonium hydrogenosulfate. Experimental results are reported on the influence of the ultrasonic power on the yields. The optimum efficiency of ultrasound is determined and the way in which ultrasound power may affect the

  7. Measurement of the charge in a double layer at a solid\\/liquid interface. Use of a conducting polymer

    Microsoft Academic Search

    Pierre Chartier; Benjamin Mattes; Howard Reiss

    1992-01-01

    Using the analysis of the measured change in double layer potential that attends the transfer of a polyaniline electrode from a reference solution to one with a different pH, the double layer charge at the solid\\/liquid interface of HCl and NaCl and the emeraldine form of polyaniline is measured. 7 refs., 2 figs., 1 tab.

  8. THE IMPACT OF MEMBRANE SOLID LIQUID SEPARATION ON THE DESIGN OF BIOLOGICAL NUTRIENT REMOVAL ACTIVATED SLUDGE SYSTEMS

    Microsoft Academic Search

    M. Ramphao; M. C. Wentzel; R. Merritt; G. A. Ekama

    2004-01-01

    Installing membranes for solid-liquid separation into BNR activated sludge (AS) systems makes a profound difference not only to the design of the BNR system itself but also to the design approach for the whole WWTP. The PWWF fixes the membrane surface area that is required in the aerobic zone and therefore fixes the aerobic zone volume. This in turn fixes

  9. Synthesis of cinnamyl acetate by solid–liquid phase transfer catalysis: Kinetic study with a batch reactor

    Microsoft Academic Search

    Venu Gopal Devulapelli; Hung-Shan Weng

    2009-01-01

    The present study reports the synthesis of cinnamyl acetate (ROAc) from cinnamyl bromide (RBr) and sodium acetate (NaOAc) in a batch reactor using quaternary ammonium bromide (QBr) as a phase transfer catalyst under a solid–liquid reaction mode. The factors affecting the reaction such as kind of catalyst, agitation speed, temperature, amount of catalyst, mole ratio of cinnamyl bromide to sodium

  10. The melting point of ice Ih for common water models calculated from direct coexistence of the solid-liquid interface

    Microsoft Academic Search

    Ramón García Fernández; José L. F. Abascal; Carlos Vega

    2006-01-01

    In this work we present an implementation for the calculation of the melting point of ice Ih from direct coexistence of the solid-liquid interface. We use molecular dynamics simulations of boxes containing liquid water and ice in contact. The implementation is based on the analysis of the evolution of the total energy along NpT simulations at different temperatures. We report

  11. Conception, elaboration et mise a l'essai d'un simulateur interactif permettant une approche modelisante: Application aux lois de la genetique mendelienne

    Microsoft Academic Search

    Abdel-Halim Lasri

    1997-01-01

    Dans cette recherche-developpement, nous avons concu, developpe et mis a l'essai un simulateur interactif pour favoriser l'apprentissage des lois probabilistes impliqees dans la genetique mendelienne. Cet environnement informatise devra permettre aux etudiants de mener des experiences simulees, utilisant les statistiques et les probebilites comme outils mathematiques pour modeliser le phenomene de la transmission des caracteres hereditaires. L'approche didactique est essentiellement

  12. LECTURE MULTI THEORIQUE DE LA PERIODE DE TRANSITION AUX NORMES IAS/IFRS

    E-print Network

    Boyer, Edmond

    LECTURE MULTI THEORIQUE DE LA PERIODE DE TRANSITION AUX NORMES IAS/IFRS : UNE ANALYSE LEXICALE DE : La première application des normes comptables internationales IAS/IFRS a suscité une communication la communication financière liée à la transition aux IAS/IFRS. Pour cela nous avons effectué une

  13. La fiscalit des fonds de pension aux Etats-Unis 1 Anne Lavigne

    E-print Network

    Paris-Sud XI, Université de

    1 La fiscalité des fonds de pension aux Etats-Unis 1 Anne Lavigne Laboratoire d'économie d'agit de décrire les dispositifs fiscaux applicables aux fonds de pension, que ces dispositifs concernent) for the workers who did not have access to firm-sponsored pension plans. In 1981, the Economic Recovery Tax Act

  14. DETERMINATION OF SOLID-LIQUID EQUILIBRIA DATA FOR MIXTURES OF HEAVY HYDROCARBONS IN A LIGHT SOLVENT

    SciTech Connect

    F.V. Hanson; J.V. Fletcher; Karthik R.

    2003-06-01

    A methodology was developed using an FT-IR spectroscopic technique to obtain solid-liquid equilibria (SLE) data for mixtures of heavy hydrocarbons in significantly lighter hydrocarbon diluents. SLE was examined in multiple Model Oils that were assembled to simulate waxes. The various Model oils were comprised of C-30 to C-44 hydrocarbons in decane. The FT-IR technique was used to identify the wax precipitation temperature (WPT). The DSC technique was also used in the identification of the onset of the two-phase equilibrium in this work. An additional Model oil made up of C-20 to C-30 hydrocarbons in decane was studied using the DSC experiment. The weight percent solid below the WPT was calculated using the FT-IR experimental results. The WPT and the weight percent solid below the WPT were predicted using an activity coefficient based thermodynamic model. The FT-IR spectroscopy method is found to successfully provide SLE data and also has several advantages over other laboratory-based methods.

  15. Biodegradation of Endocrine Disruptors in Solid-Liquid Two-Phase Partitioning Systems by Enrichment Cultures

    PubMed Central

    dos Santos, Silvia Cristina Cunha; Ouellette, Julianne; Juteau, Pierre; Lépine, François; Déziel, Eric

    2013-01-01

    Naturally occurring and synthetic estrogens and other molecules from industrial sources strongly contribute to the endocrine disruption of urban wastewater. Because of the presence of these molecules in low but effective concentrations in wastewaters, these endocrine disruptors (EDs) are only partially removed after most wastewater treatments, reflecting the presence of these molecules in rivers in urban areas. The development of a two-phase partitioning bioreactor (TPPB) might be an effective strategy for the removal of EDs from wastewater plant effluents. Here, we describe the establishment of three ED-degrading microbial enrichment cultures adapted to a solid-liquid two-phase partitioning system using Hytrel as the immiscible water phase and loaded with estrone, estradiol, estriol, ethynylestradiol, nonylphenol, and bisphenol A. All molecules except ethynylestradiol were degraded in the enrichment cultures. The bacterial composition of the three enrichment cultures was determined using 16S rRNA gene sequencing and showed sequences affiliated with bacteria associated with the degradation of these compounds, such as Sphingomonadales. One Rhodococcus isolate capable of degrading estrone, estradiol, and estriol was isolated from one enrichment culture. These results highlight the great potential for the development of TPPB for the degradation of highly diluted EDs in water effluents. PMID:23728808

  16. Kinetics of Assembly of ``Looped'' Brushes at the Solid-Liquid Interface

    NASA Astrophysics Data System (ADS)

    Alonzo, Jose

    2005-03-01

    Dense layers of end-tethered polymers, often called polymer brushes, are of interest for their ability to modify interfacial properties. Along these lines, creating brushes comprised of loops by tethering the chains by both ends offers potential advantages in tailoring the adhesive or frictional properties of surfaces. Rigorously synthesized poly(2-vinylpyridine)-polystyrene-poly(2-vinylpyridine) triblock copolymers were used as a model system to examine the formation of looped brushes at the solid-liquid interface. In-situ phase modulated ellipsometry measurements were made to study the kinetics of assembly of these copolymers onto silicon surfaces. This technique allows the adsorbed amount and ellipsometric height of the layer to be sensitively measured as a function of time. These experiments provide evidence of loop formation: specifically, while the adsorbed amount increases asymptotically, the thickness shows an ``overshoot'' during the initial stages of adsorption followed by a slow reorganization. The final thickness of the looped brush is approximately one-half of that expected for a single-end tethered brush made from a diblock copolymer with a buoy block of similar molecular weight. The effect of triblock molecular weight and composition on layer assembly and structure will also be discussed.

  17. Solid-liquid interface free energies of pure bcc metals and B2 phases.

    PubMed

    Wilson, S R; Gunawardana, K G S H; Mendelev, M I

    2015-04-01

    The solid-liquid interface (SLI) free energy was determined from molecular dynamics (MD) simulation for several body centered cubic (bcc) metals and B2 metallic compounds (space group: Pm3?m; prototype: CsCl). In order to include a bcc metal with a low melting temperature in our study, a semi-empirical potential was developed for Na. Two additional synthetic "Na" potentials were also developed to explore the effect of liquid structure and latent heat on the SLI free energy. The obtained MD data were compared with the empirical Turnbull, Laird, and Ewing relations. All three relations are found to predict the general trend observed in the MD data for bcc metals obtained within the present study. However, only the Laird and Ewing relations are able to predict the trend obtained within the sequence of "Na" potentials. The Laird relation provides the best prediction for our MD data and other MD data for bcc metals taken from the literature. Overall, the Laird relation also agrees well with our B2 data but requires a proportionality constant that is substantially different from the bcc case. It also fails to explain a considerable difference between the SLI free energies of some B2 phases which have nearly the same melting temperature. In contrast, this difference is satisfactorily described by the Ewing relation. Moreover, the Ewing relation obtained from the bcc dataset also provides a reasonable description of the B2 data. PMID:25854256

  18. Coarsening in Solid-Liquid Mixtures-2: A Materials Science Experiment for the ISS

    NASA Technical Reports Server (NTRS)

    Hickman, J. Mark; Voorhees, Peter W.; Kwon, Yongwoo; Lorik, Tibor

    2004-01-01

    A materials science experiment has been developed and readied for operation aboard the International Space Station (ISS). Components of this experiment are onboard ISS and area awaiting the flight of science samples. The goal of the experiment is to understand the dynamics of Ostwald ripening, also known as coarsening, a process that occurs in nearly any two-phase mixture found in nature. Attempts to obtain experimental data in ground-based laboratories are hindered due to the presence of gravity, which introduces material transport modes other than that of the coarsening phenomenon. This introduces adjustable parameters in the formulation of theory. The original Coarsening in Solid-Liquid Mixtures (CSLM) mission, which flew on the Space Shuttle in 1997, produced data from a coarsened eutectic alloy. Unfortunately, both the science matrix and the hardware, while nominally functional, did not account adequately for operations in microgravity. A significantly redesigned follow-on experiment, CSLM-2 has been developed to redress the inadequacies of the original experiment. This paper reviews the CSLM-2 project: its history, science goals, flight hardware implementation, and planned operations and analysis

  19. Focused ultrasound solid-liquid extraction for the determination of organic biomarkers in beachrocks.

    PubMed

    Blanco-Zubiaguirre, L; Arrieta, N; Iturregui, A; Martinez-Arkarazo, I; Olivares, M; Castro, K; Olazabal, M A; Madariaga, J M

    2015-11-01

    Beachrocks are consolidated coastal sedimentary formations resulting mainly from the relative rapid cementation of beach sediments by different calcium carbonate polymorphs. Although previous works have already studied the elemental composition and the mineral phases composing these cements, few of them have focused their attention on the organic matter present therein. This work describes an extraction methodology based on focused ultrasound solid-liquid extraction (FUSLE), followed by analysis using large volume injection (LVI) in a programmable temperature vaporizer (PTV) combined with gas chromatography-mass spectrometry (GC-MS) in order to determine organics such as polycyclic aromatic hydrocarbons (PAHs) and biomarkers (hopanes), which can increase and confirm the information obtained so far. This goal has been achieved after the optimization of the main parameters affecting the extraction procedure, such as, extraction solvent, FUSLE variables (amplitude, extraction time and pulse time) and also variables affecting the LVI-PTV (vent time, injection speed and cryo-focusing temperature). The developed method rendered results comparable to traditional extraction methods in terms of accuracy (77-109%) and repeatability (RSD<23%). Finally, the analyses performed over real beachrock samples from the Bay of Biscay (Northern Spain) revealed the presence of the 16 EPA priority PAHs, as well as some organic biomarkers which could increase the knowledge about such beachrock formation. PMID:26186864

  20. Biodegradation of endocrine disruptors in solid-liquid two-phase partitioning systems by enrichment cultures.

    PubMed

    Villemur, Richard; Dos Santos, Silvia Cristina Cunha; Ouellette, Julianne; Juteau, Pierre; Lépine, François; Déziel, Eric

    2013-08-01

    Naturally occurring and synthetic estrogens and other molecules from industrial sources strongly contribute to the endocrine disruption of urban wastewater. Because of the presence of these molecules in low but effective concentrations in wastewaters, these endocrine disruptors (EDs) are only partially removed after most wastewater treatments, reflecting the presence of these molecules in rivers in urban areas. The development of a two-phase partitioning bioreactor (TPPB) might be an effective strategy for the removal of EDs from wastewater plant effluents. Here, we describe the establishment of three ED-degrading microbial enrichment cultures adapted to a solid-liquid two-phase partitioning system using Hytrel as the immiscible water phase and loaded with estrone, estradiol, estriol, ethynylestradiol, nonylphenol, and bisphenol A. All molecules except ethynylestradiol were degraded in the enrichment cultures. The bacterial composition of the three enrichment cultures was determined using 16S rRNA gene sequencing and showed sequences affiliated with bacteria associated with the degradation of these compounds, such as Sphingomonadales. One Rhodococcus isolate capable of degrading estrone, estradiol, and estriol was isolated from one enrichment culture. These results highlight the great potential for the development of TPPB for the degradation of highly diluted EDs in water effluents. PMID:23728808

  1. Probing helium mass flow through a solid-liquid-solid double junction

    NASA Astrophysics Data System (ADS)

    Cheng, Zhigang; Beamish, John; Fefferman, Andrew; Souris, Fabien; Balibar, Sebastien

    2015-03-01

    Recent experiments by Hallock and coworkers observed mass transport through solid 4He and suggested it was due to flow along dislocation lines. In those measurements, helium was injected and removed through Vycor ``electrodes'' filled with superfluid 4He. Here, we report the results of a related experiment: a Vycor rod filled with superfluid 4He is sandwiched between two bulk solid regions. By compressing solid 4He on one side and measuring pressure changes on the other, we can detect flow through the Vycor, without necessarily having flow through the solid. In high pressure crystals we saw no flow below 1 K but in samples below 28 bar we observed flow down to the lowest temperatures (below 20 mK). The temperature dependence of this flow was very similar to that of the flow seen in previous experiments: it began around 600 mK, increased as the temperature was reduced, then decreased dramatically at a temperature which depended on 3He impurity concentration (around 75 mK for standard isotopic purity samples). We suggest that flow in solid 4He experiments is limited by mass transfer through the solid-liquid interface at the Vycor ends. Funding provided by NSERC Canada and by ERC (AdG 247258-SUPERSOLID).

  2. Coarsening in Solid-liquid Mixtures: Overview of Experiments on Shuttle and ISS

    NASA Technical Reports Server (NTRS)

    Duval, Walter M. B.; Hawersaat, Robert W.; Lorik, T.; Thompson, J.; Gulsoy, B.; Voorhees, P. W.

    2013-01-01

    The microgravity environment on the Shuttle and the International Space Station (ISS) provides the ideal condition to perform experiments on Coarsening in Solid-Liquid Mixtures (CSLM) as deleterious effects such as particle sedimentation and buoyancy-induced convection are suppressed. For an ideal system such as Lead-Tin in which all the thermophysical properties are known, the initial condition in microgravity of randomly dispersed particles with local clustering of solid Tin in eutectic liquid Lead-Tin matrix, permitted kinetic studies of competitive particle growth for a range of volume fractions. Verification that the quenching phase of the experiment had negligible effect of the spatial distribution of particles is shown through the computational solution of the dynamical equations of motion, thus insuring quench-free effects from the coarsened microstructure measurements. The low volume fraction experiments conducted on the Shuttle showed agreement with transient Ostwald ripening theory, and the steady-state requirement of LSW theory was not achieved. More recent experiments conducted on ISS with higher volume fractions have achieved steady-state condition and show that the kinetics follows the classical diffusion limited particle coarsening prediction and the measured 3D particle size distribution becomes broader as predicted from theory.

  3. Metastable nanobubbles at the solid-liquid interface due to contact angle hysteresis.

    PubMed

    Nishiyama, Takashi; Yamada, Yutaka; Ikuta, Tatsuya; Takahashi, Koji; Takata, Yasuyuki

    2015-01-27

    Nanobubbles exist at solid-liquid interfaces between pure water and hydrophobic surfaces with very high stability, lasting in certain cases up to several days. Not only semispherical but also other shapes, such as micropancakes, are known to exist at such interfaces. However, doubt has been raised as to whether or not the nanobubbles are gas-phase entities. In this study, surface nanobubbles at a pure water-highly ordered pyrolytic graphite (HOPG) interface were investigated by peak force quantitative nanomechanics (PF-QNM). Multiple isolated nanobubbles generated by the solvent-exchange method were present on the terraced areas, avoiding the steps of the HOPG surface. Adjacent nanobubbles coalesced and formed metastable nanobubbles. Coalescence was enhanced by the PF-QNM measurement. We determined that nanobubbles can exist for a long time because of nanoscale contact angle hysteresis at the water-HOPG interface. Moreover, the hydrophilic steps of HOPG were avoided during coalescence, providing evidence that the nanobubbles are truly gas phase. PMID:25540821

  4. How solid-liquid adhesive property regulates liquid slippage on solid surfaces?

    PubMed

    Xue, Yahui; Wu, Yang; Pei, Xiaowei; Duan, Huiling; Xue, Qunji; Zhou, Feng

    2015-01-13

    The influence of solid-liquid adhesive property on liquid slippage at solid surfaces has been investigated using experiment approach on well-defined model surfaces as well as theoretical analysis. Based on a classical molecular-kinetic description for molecular and hydrodynamic slip, we propose a simple theoretical model that directly relates the liquid slip length to the liquid adhesive force on solid surfaces, which yields an exponential decay function. Well-defined smooth surfaces with varied surface wettability/adhesion are fabricated by forming self-assembled monolayers on gold with different mole ratios of hydrophobic and hydrophilic thiols. The adhesive force of a water droplet and the molecular slippage on these surfaces are probed by surface force apparatus and quartz crystal microbalance measurements, respectively. The experiment results are well consistent with our theoretical prediction. Our finding benefits the understanding of the underlying mechanism of liquid slippage on solid surfaces at molecular level and the rational design of microfluidics with an aim to be frictionless or highly controllable. PMID:25511171

  5. Fluctuations and Criticality of a Granular Solid-Liquid-Like Phase Transition

    NASA Astrophysics Data System (ADS)

    Castillo, Gustavo; Mujica, Nicolás; Soto, Rodrigo

    2012-08-01

    We present an experimental study of density and order fluctuations in the vicinity of the solid-liquid-like transition that occurs in a vibrated quasi-two-dimensional granular system. The two-dimensional projected static and dynamic correlation functions are studied. We show that density fluctuations, characterized through the structure factor, increase in size and intensity as the transition is approached, but they do not change significantly at the transition itself. The dense, metastable clusters, which present square symmetry, also increase their local order in the vicinity of the transition. This is characterized through the bond-orientational order parameter Q4, which in Fourier space shows an Ornstein-Zernike-like behavior. Depending on the filling density and vertical height, the transition can be of first- or second-order type. In the latter case, the associated correlation length ?4, the relaxation time ?4, the zero k limit of Q4 fluctuations (static susceptibility), the pair correlation function of Q4, and the amplitude of the order parameter obey critical power laws, with saturations due to finite size effects. Their respective critical exponents are ??=1, ??=2, ?=1, ?=0.67, and ?=1/2, whereas the dynamical critical exponent z=??/??=2. These results are consistent with model C of dynamical critical phenomena, valid for a nonconserved critical order parameter (bond-orientation order) coupled to a conserved field (density).

  6. Molecular Dynamics Study of Freezing Point and Solid-Liquid Interfacial Free Energy of Stockmayer Fluids

    SciTech Connect

    Wang, J. [University of Nebraska, Lincoln; Apte, Pankaj [Indian Institute of Technology, Kanpur; Morris, James R [ORNL; Zeng, X.C. [University of Nebraska, Lincoln

    2013-01-01

    Freezing temperatures of Stockmayer fluids with different dipolar strength at zero pressure are estimated and computed using three independent molecular-dynamics (MD) simulation methods, namely, the superheating-undercooling method, the constant-pressure and constant-temperature (NPT) two phase coexistence method, and the constant-pressure and constant-enthalpy (NPH) coexistence method. The best estimate of the freezing temperature (in reduced unit) for the Stockmayer (SM) fluid with a reduced dipole moment is 0.656 0.001, 0.726 0.002 and 0.835 0.005, respectively. The freezing temperature increases with the dipolar strength. The solid-liquid interfacial free energies of the (111), (110) and (100) interface are calculated for the first time using two independent methods, namely, the cleaving-wall method and the interfacial fluctuation method. Both methods predict that the interfacial free energy increases with the dipole moment. Although the interfacial fluctuation method suggests a weaker interfacial anisotropy, particularly for strongly dipolar SM fluids, both methods predicted the same trend of interfacial anisotropy, that is, .

  7. Solid-liquid separation of oxidized americium from fission product lanthanides

    NASA Astrophysics Data System (ADS)

    Shehee, T. C.; Martin, L. R.; Nash, K. L.

    2010-03-01

    The separation of americium from the lanthanides and curium is a requirement if transmutation of americium is to be performed in advanced nuclear fuel cycles. Oxidation of Am3+ to AmO2+ or AmO22+ may allow separation of Am from Ln and Cm in one step, since the lanthanides and curium do not have higher oxidation states as accessible. Two possible solid-liquid separation methods have been developed to address this difficult separation. Under acidic conditions using oxone or persulfate, the oxidation and retention of tracer Am in the aqueous phase has been observed with a separation factor of 11 ± 1. Most of these studies have been conducted using 237NpO2(NO3), 233UO2(NO3)2, 238Pu(NO3)4 and 241Am(NO3)3 at radiotracer concentrations. Lanthanides precipitate as the sodium or potassium europium double sulfate salt. Under basic conditions, ozone oxidation of Am(CO3)OH(s) solubilizes Am from a lanthanide carbonate hydroxide solid phase to the aqueous phase as the AmO2(CO3)34-or AmO2(CO3)35- species. For the ozone oxidation of the americium tracer a separation factor of 1.6 ± 0.8 and 47 ± 2 for the oxidation/separation in Na2CO3 and NaHCO3 respectively.

  8. Simulations of solid-liquid friction at ice-Ih/water interfaces

    NASA Astrophysics Data System (ADS)

    Louden, Patrick B.; Gezelter, J. Daniel

    2013-11-01

    We have investigated the structural and dynamic properties of the basal and prismatic facets of the ice Ih/water interface when the solid phase is drawn through the liquid (i.e., sheared relative to the fluid phase). To impose the shear, we utilized a velocity-shearing and scaling approach to reverse non-equilibrium molecular dynamics. This method can create simultaneous temperature and velocity gradients and allow the measurement of transport properties at interfaces. The interfacial width was found to be independent of the relative velocity of the ice and liquid layers over a wide range of shear rates. Decays of molecular orientational time correlation functions gave similar estimates for the width of the interfaces, although the short- and longer-time decay components behave differently closer to the interface. Although both facets of ice are in "stick" boundary conditions in liquid water, the solid-liquid friction coefficients were found to be significantly different for the basal and prismatic facets of ice.

  9. Simulations of solid-liquid friction at ice-I(h)/water interfaces.

    PubMed

    Louden, Patrick B; Gezelter, J Daniel

    2013-11-21

    We have investigated the structural and dynamic properties of the basal and prismatic facets of the ice Ih/water interface when the solid phase is drawn through the liquid (i.e., sheared relative to the fluid phase). To impose the shear, we utilized a velocity-shearing and scaling approach to reverse non-equilibrium molecular dynamics. This method can create simultaneous temperature and velocity gradients and allow the measurement of transport properties at interfaces. The interfacial width was found to be independent of the relative velocity of the ice and liquid layers over a wide range of shear rates. Decays of molecular orientational time correlation functions gave similar estimates for the width of the interfaces, although the short- and longer-time decay components behave differently closer to the interface. Although both facets of ice are in "stick" boundary conditions in liquid water, the solid-liquid friction coefficients were found to be significantly different for the basal and prismatic facets of ice. PMID:24320347

  10. Conception, elaboration et mise a l'essai d'un simulateur interactif permettant une approche modelisante: Application aux lois de la genetique mendelienne

    NASA Astrophysics Data System (ADS)

    Lasri, Abdel-Halim

    Dans cette recherche-developpement, nous avons concu, developpe et mis a l'essai un simulateur interactif pour favoriser l'apprentissage des lois probabilistes impliqees dans la genetique mendelienne. Cet environnement informatise devra permettre aux etudiants de mener des experiences simulees, utilisant les statistiques et les probebilites comme outils mathematiques pour modeliser le phenomene de la transmission des caracteres hereditaires. L'approche didactique est essentiellement orientee vers l'utilisation des methodes quantitatives impliquees dans l'experimentation des facteurs hereditaires. En incorporant au simulateur le principe de la "Lunette cognitive" de Nonnon (1986), l'etudiant fut place dans une situation ou il a pu synchroniser la perception de la representation iconique (concrete) et symbolique (abstraite) des lois probabilistes de Mendel. A l'aide de cet environnement, nous avons amene l'etudiant a identifier le(s) caractere(s) hereditaire(s) des parents a croiser, a predire les frequences phenotypiques probables de la descendance issue du croisement, a observer les resultats statistiques et leur fluctuation au niveau de l'histogramme des frequences, a comparer ces resultats aux predictions anticipees, a interpreter les donnees et a selectionner en consequence d'autres experiences a realiser. Les etapes de l'approche inductive sont privilegiees du debut a la fin des activites proposees. L'elaboration, du simulateur et des documents d'accompagnement, a ete concue a partir d'une vingtaine de principes directeurs et d'un modele d'action. Ces principes directeurs et le modele d'action decoulent de considerations theoriques psychologiques, didactiques et technologiques. La recherche decrit la structure des differentes parties composant le simulateur. L'architecture de celui-ci est construite autour d'une unite centrale, la "Principale", dont les liens et les ramifications avec les autres unites confere a l'ensemble du simulateur sa souplesse et sa facilite d'utilisation. Le simulateur "Genetique", a l'etat de prototype, et la documentation qui lui est afferente ont ete soumis a deux mises a l'essai: l'une fonctionnelle, l'autre empirique. La mise a l'essai fonctionnelle, menee aupres d'un groupe d'enseignants experts, a permis d'identifier les lacunes du materiel elabore afin de lui apporter les reajustements qui s'imposaient. La mise a l'essai empirique, conduite par un groupe de onze (11) etudiants de niveau secondaire, avait pour but, d'une part, de tester la facilite d'utilisation du simulateur "Genetique" ainsi que les documents d'accompagnement et, d'autre part, de verifier si les participants retiraient des avantages pedagogiques de cet environnement. Trois techniques furent exploitees pour recolter les donnees de la mise a l'essai empirique. L'analyse des resultats a permis de faire un retour critique sur les productions concretes de cette recherche et d'apporter les modifications necessaires tant au simulateur qu'aux documents d'accompagnement. Cette analyse a permis egalement de conclure que notre simulateur interactif favorise une approche inductive permettant aux etudiants de s'approprier les lois probabilistes de Mendel. Enfin, la conclusion degage des pistes de recherches destinees aux etudes ulterieures, plus particulierement celles qui s'interessent a developper des simulateurs, afin d'integrer a ceux-ci des representations concretes et abstraites presentees en temps reel. Les disquettes du simulateur "Genetique" et les documents d'accompagnement sont annexes a la presente recherche.

  11. Study of the generation characteristics of laser converters with dye-based wide-aperture solid--liquid active elements

    SciTech Connect

    Eremenko, A.S.; Zemskii, V.I.; Kolesnikov, Y.L.; Malinin, B.G.; Meshkovsky, I.K.; Savkin, N.P.; Stepanov, V.E.; Shildyaev, V.S.

    1986-11-01

    The lasing characteristics of an active element, consisting of a fine porous silicate matrix, has been studied. Molecules of a dye (rhodamine 6G) and an ethanol solution of the same dye were introduced into the cells. It has been shown that under conditions of large heat release (when thermooptical distortions begin to appear in the dye solutions), the solid--liquid element preserves the stability of its own lasing characteristics.

  12. Modelling of the pre-arcing period in HBC fuses including solid - liquid - vapour phase changes of the fuse element

    Microsoft Academic Search

    D. Rochette; W. Bussiere; R. Touzani; S. Memiaghe; G. Velleaud; P. Andre

    2007-01-01

    In this paper, we present a model and a numerical method of the fuse element heating including solid-liquid-vapour phase transitions in order to evaluate the pre-arcing time in HBC fuses. The mathematical model is based on the enthalpy formulation of the heat equation with a source term representing the Joule effect coupled with the Laplace equation for the potential and

  13. Influence of ultrasound power on the alkylation of phenylacetonitrile under solid-liquid phase transfer catalysis conditions.

    PubMed

    Guilet, R; Berlan, J; Louisnard, O; Schwartzentruber, J

    1998-03-01

    The influence of ultrasound power on the C-alkylation of phenylacetonitrile by ethyl bromide was studied under solid-liquid phase transfer catalysis in the presence of potassium hydroxide and tetrabutylammonium hydrogenosulfate. Experimental results are reported on the influence of the ultrasonic power on the yields. The optimum efficiency of ultrasounds is determined and the way in which ultrasound power may affect the yields is discussed. PMID:11270331

  14. Thermodynamic and rheological properties of solid-liquid systems in coal processing. Quarterly technical report, October 1--December 31, 1994

    SciTech Connect

    Kabadi, V.N.; Ilias, S.

    1995-10-01

    The objective of this project is to develop a model for solid-liquid equilibria and a model for viscosities of the products of coal liquefaction processes. The same characterization procedure and representation by continuous distributions as used in previous work on vapor-liquid equilibria and excess enthalpies of coal liquids will be used. Models when fully developed will give the solid-liquid phase equilibrium properties and viscosities as factors of temperature and pressure for known molecular weight distribution and structural characterization of the coal liquid. To accomplish this well, the project requires three tasks: (1) Solid-Liquid phase equilibrium model development; (2) Experimental Viscosity Measurements; and (3) Viscosity Model Development. The work on development of a predictive model for saturated liquid volumes of coal model compounds has been completed. A manuscript has been prepared for submission to AIChE Journal. A copy of the manuscript is attached. Work on extending the viscosity model to coal derived liquids is continuing and progress on this work will be included in the next report.

  15. Digestion of frozen/thawed food waste in the hybrid anaerobic solid-liquid system

    SciTech Connect

    Stabnikova, O. [School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)], E-mail: costab@ntu.edu.sg; Liu, X.Y.; Wang, J.Y. [School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

    2008-07-01

    The hybrid anaerobic solid-liquid (HASL) system, which is a modified two-phase anaerobic digester, is to be used in an industrial scale operation to minimize disposal of food waste at incineration plants in Singapore. The aim of the present research was to evaluate freezing/thawing of food waste as a pre-treatment for its anaerobic digestion in the HASL system. The hydrolytic and fermentation processes in the acidogenic reactor were enhanced when food waste was frozen for 24 h at -20 deg. C and then thawed for 12 h at 25 deg. C (experiment) in comparison with fresh food waste (control). The highest dissolved COD concentrations in the leachate from the acidogenic reactors were 16.9 g/l on day 3 in the control and 18.9 g/l on day 1 in the experiment. The highest VFA concentrations in the leachate from the acidogenic reactors were 11.7 g/l on day 3 in the control and 17.0 g/l on day 1 in the experiment. The same volume of methane was produced during 12 days in the control and 7 days in the experiment. It gave the opportunity to diminish operational time of batch process by 42%. The effect of freezing/thawing of food waste as pre-treatment for its anaerobic digestion in the HASL system was comparable with that of thermal pre-treatment of food waste at 150 deg. C for 1 h. However, estimation of energy required either to heat the suspended food waste to 150 deg. C or to freeze the same quantity of food waste to -20 deg. C showed that freezing pre-treatment consumes about 3 times less energy than thermal pre-treatment.

  16. A comparison of BNR activated sludge systems with membrane and settling tank solid-liquid separation.

    PubMed

    Ramphao, M C; Wentzel, M C; Ekama, G A; Alexander, W V

    2006-01-01

    Installing membranes for solid-liquid separation into biological nutrient removal (BNR) activated sludge (AS) systems makes a profound difference not only to the design of the membrane bio-reactor (MBR) BNR system itself, but also to the design approach for the whole wastewater treatment plant (WWTP). In multi-zone BNR systems with membranes in the aerobic reactor and fixed volumes for the anaerobic, anoxic and aerobic zones (i.e. fixed volume fractions), the mass fractions can be controlled (within a range) with the inter-reactor recycle ratios. This zone mass fraction flexibility is a significant advantage of MBR BNR systems over BNR systems with secondary settling tanks (SSTs), because it allows changing the mass fractions to optimise biological N and P removal in conformity with influent wastewater characteristics and the effluent N and P concentrations required. For PWWF/ADWF ratios (fq) in the upper range (fq approximately 2.0), aerobic mass fractions in the lower range (f(maer) < 0.60) and high (usually raw) wastewater strengths, the indicated mode of operation of MBR BNR systems is as extended aeration WWTPs (no primary settling and long sludge age). However, the volume reduction compared with equivalent BNR systems with SSTs will not be large (40-60%), but the cost of the membranes can be offset against sludge thickening and stabilisation costs. Moving from a flow unbalanced raw wastewater system to a flow balanced (fq = 1) low (usually settled) wastewater strength system can double the ADWF capacity of the biological reactor, but the design approach of the WWTP changes away from extended aeration to include primary sludge stabilisation. The cost of primary sludge treatment then has to be offset against the savings of the increased WWTP capacity. PMID:16889266

  17. Solid\\/liquid extraction of caffeine from guaraná with methylene chloride\\/Extracción solido-liquido de cafeina de guarana con cloruro de metileno

    Microsoft Academic Search

    G. J. Hulbert; R. N. Biswal; C. B. Mehr; T. H. Walker; J. L. Collins

    1998-01-01

    Methylene chloride decaffeination processes for ground and whole guaraná seed cores were evaluated. Ground seeds were contacted with solvent in shaking flasks in a controlled temperature water bath. The experimental design included three solid\\/liquid ratios [1:4, 1:6, 1:8 (w\\/w)] and two temperatures (25 and 30°C). Caffeine was also extracted from 100 g batches of whole seed cores in a solid\\/liquid

  18. INTRODUCTION AUX HOMME-MACHINE

    E-print Network

    Essert-Villard, Caroline

    en fonction de la perception visuelle puis tactile #12;10 Action physique · la main est la plus;13 Cognition : mémoire et apprentissage · mémoire sensorielle associée aux sens très court laps de temps (env dizaines de secondes · mémoire à long terme capacité infinie temps de stockage infini #12;14 Cognition

  19. Enzymatic hydrolysis of organic waste materials in a solid-liquid system.

    PubMed

    Jordan, S N; Mullen, G J

    2007-01-01

    In the current climate of increasing emphasis on environmental protection and efficient waste management, regional management bodies and environmental agencies are striving to achieve an economical and environmentally acceptable system for the recycling of biodegradable organic wastes. Composting would appear to be a cost effective solution to this problem, but in its entirety, composting is an inherently lengthy and variable process and is restrictive in terms of the demand on resources and space in composting plants. The aim of this study was to compare a biological composting process of solid residues with an enzymatic hydrolysis process of residues. The length of time required to naturally compost three organic materials, spent mushroom compost (SMC), farmyard manure (FYM) and dairy wastewater sludge (DWS) under optimal conditions was 42 days, 98 days and 84 days, respectively. In an attempt to accelerate this process, commercial enzymes were added to the waste products in a heterogeneous solid-liquid system. The enzymes utilised included a range of proteases, cellulases, ligninases, lipases and pectinases, which are responsible for the hydrolysis of protein, cellulose, lignin, lipids and carbohydrates, respectively. Preliminary results indicate that all of the organic materials were stabilised within 9h and that the enzymes used would, therefore, improve the efficiency of a waste management plant, if such a system were employed. Spent mushroom compost has a mean N/P/K ratio of 20:10:10 recorded for composted SMC, while a similar ratio of 20:10:20 was obtained for hydrolysed SMC. In contrast, composted farmyard manure has a N/P/K ratio of 30:0:30 and a ratio of 10:1:10 for hydrolysed FYM. Finally, composted DWS has a N/P/K ratio of 20:1:30 while DWS hydrolysate has a N/P/K ratio of 40:1:20, with the decrease in nitrogen in the composted DWS attributed to the addition of wood chippings and sawdust as a bulking agent. While all three materials have a considerable supply of plant nutrients, the variability in nutrients could be overlooked when employed as a soil amendment. PMID:17391952

  20. A computational model for the analysis of diffusive binary alloy solid/liquid phase change energy transport

    NASA Technical Reports Server (NTRS)

    Schneider, G. E.

    1991-01-01

    A model is presented for the prediction of solid/liquid, binary alloy, phase change energy transport. The model incorporates only one-dimensional, diffusive transport of both energy and species but is not inherently limited in any way to such a restriction. The model incorporates a previously developed algorithm for single constituent phase change energy transport and is applied to the energy transport as well as the species transport aspects of the problem. The model is applied to four example cooling problems and is shown to perform exceedingly well from an algorithmic point of view.

  1. Bubble Induced Disruption of a Planar Solid-Liquid Interface During Controlled Directional Solidification in a Microgravity Environment

    NASA Technical Reports Server (NTRS)

    Grugel, Richard N.; Brush, Lucien N.; Anilkumar, Amrutur V.

    2013-01-01

    Pore Formation and Mobility Investigation (PFMI) experiments were conducted in the microgravity environment aboard the International Space Station with the intent of better understanding the role entrained porosity/bubbles play during controlled directional solidification. The planar interface in a slowing growing succinonitrile - 0.24 wt% water alloy was being observed when a nitrogen bubble traversed the mushy zone and remained at the solid-liquid interface. Breakdown of the interface to shallow cells subsequently occurred, and was later evaluated using down-linked data from a nearby thermocouple. These results and other detrimental effects due to the presence of bubbles during solidification processing in a microgravity environment are presented and discussed.

  2. In Situ Monitoring of Solid-Liquid Interface of Aluminum Alloy Using High-Temperature Ultrasonic Sensor

    NASA Astrophysics Data System (ADS)

    Ihara, Ikuo; Burhan, Dikky; Seda, Yoshihisa

    2005-06-01

    A high temperature ultrasonic sensor with a titanium buffer rod has been applied to the in situ monitoring of the solid-liquid interface of an aluminum alloy (Al-12.6%Si) during unidirectional solidification at 700°C. The ultrasonic sensor consists of a conventional piezoelectric transducer, a titanium buffer rod as an acoustic waveguide and a cooling system. Its length is approximately 300 mm. This ultrasonic sensor, because of the unique characteristics of titanium, provides not only good acoustic coupling to molten aluminum but also high-corrosion resistance. Pulse echo measurements in the molten aluminum alloy are performed using the sensor at 2.25 MHz. A clear reflected echo from a stable solid-liquid interface of the aluminum alloy has been successfully monitored. In addition, the reflected echo from the growing interface during unidirectional solidification has also been monitored. The growth rate of the interface was determined to be 0.12 mm/s from the monitored echo.

  3. Experimental study of the solid-liquid interface in a yield-stress fluid flow upstream of a step

    NASA Astrophysics Data System (ADS)

    Luu, Li-Hua; Philippe, Pierre; Chambon, Guillaume

    2015-01-01

    We present an experimental study investigating the transition zone between a liquid-like unyielded region and a solid-like yielded region in a yield-stress fluid. The configuration consists of a rectangular closed-channel flow disturbed by the presence of a step. Upstream of the step, a solid-liquid interface between a dead zone and a flow zone appears. In this study, we use a model fluid, namely polymer micro-gel Carbopol, which exhibits Herschel-Bulkley viscoplastic rheology. Exploiting the fluid transparency, the flow is monitored by particle image velocimetry using an internal visualization technique. The main outcome of this study is to show that, except in a thin transition layer close to the solid-liquid interface, the flow behaves as an apparent Poiseuille flow with an apparent slip condition at the base. The slip frontier is found to be almost independent of the flow rate while the corresponding slip velocity increases with the flow rate.

  4. III -INTRODUCTION AUX TESTS STATISTIQUES

    E-print Network

    Croisille, Jean-Pierre

    III - INTRODUCTION AUX TESTS STATISTIQUES J-P. Croisille Universit´e de Lorraine UEL - Ann´ee 2012/2013 Jean-Pierre CROISILLE - Laboratoire LMAM UEL: L'influence des math´ematiques sur la soci´et´e #12 LMAM UEL: L'influence des math´ematiques sur la soci´et´e #12;CHOIX DE L'HYPOTHESE NEUTRE ET DE L

  5. Aide aux doctorants pour la participation des Aide aux doctorants pour la participation des colloques

    E-print Network

    Di Girolami, Cristina

    Aide aux doctorants pour la participation à des colloques Aide aux doctorants pour la participation à des colloques retour Formation doctorale Aide aux doctorants pour la participation à des colloques aide vient compléter les financements déjà prévus par les laboratoires et les Écoles doctorales pour

  6. Exploring the solid-liquid phase change of an adapted Dzugutov model using generalized replica exchange method.

    PubMed

    Lu, Qing; Kim, Jaegil; Straub, John E

    2012-07-26

    The generalized replica exchange method (gREM) is applied to simulate a solid-liquid phase change in an adapted Dzugutov model system. The idea of gREM is to incorporate the merit of sampling from a generalized ensemble into the replica exchange paradigm. The generalized ensemble weights are determined from effective temperatures tailored for this system, through an inverse mapping strategy. The ordered and disordered phases are smoothly joined together through a succession of unimodal energy distributions, providing a continuous transformation from an isotropic liquid into an amorphous solid phase under the given condition. The phase change temperature is determined by evaluation of various thermodynamic and structural order parameters. The increasing tendency for icosahedral local order under cooling is quantified using bond order parameters. The ergodic measure is used to demonstrate the advantage of gREM over the traditional temperature-based REM in sampling the phase change region. PMID:22452532

  7. Resonant anomalous x-ray reflectivity as a probe of ion adsorption at solid-liquid interfaces.

    SciTech Connect

    Fenter, P.; Park, C.; Nagy, K. L.; Sturchio, N. C.; Chemistry; Univ. of Illinois at Chicago

    2007-05-23

    We discuss new opportunities to understand processes at the solid-liquid interface using resonant anomalous X-ray reflectivity (RAXR). This approach is illustrated by determination of element-specific density profiles at mica surfaces in aqueous electrolyte solutions containing Rb{sup +} and Sr{sup 2+}. The total interfacial electron density profile is determined by specular reflectivity (i.e., reflected intensity vs. momentum transfer, q, at an energy, E, far from any characteristic absorption edge). RAXR spectra (i.e., intensity vs. E at fixed q) reveal element-specific ion distributions. Key differences in the interaction of Rb{sup +} and Sr{sup 2+} with mica are observed using resonant anomalous X-ray reflectivity: Rb{sup +} adsorbs in a partially hydrated state, but Sr{sup 2+} adsorbs in both fully and partially hydrated states.

  8. A Dynamic Model for the Interaction Between an Insoluble Particle and an Advancing Solid/Liquid Interface

    NASA Technical Reports Server (NTRS)

    Catalina, A. V.; Mukherjee, S.; Stefanescu, D. M.

    2000-01-01

    Most models that describe the interaction of an insoluble particle with an advancing solid-liquid interface are based on the assumption of steady state. However, as demonstrated by experimental work, the process does not reach steady state until the particle is pushed for a while by the interface. In this work, a dynamic mathematical model was developed. The dynamic model demonstrates that this interaction is essentially non-steady state and that steady state eventually occurs only when solidification is conducted at sub-critical velocities. The model was tested for three systems: aluminum-zirconia particles, succinonitrilepolystyrene particles, and biphenyl-glass particles. The calculated values for critical velocity of the pushing/engulfment transition were in same range with the experimental ones.

  9. Nanostructuring of self-assembled porphyrin networks at a solid/liquid interface: local manipulation under global control.

    PubMed

    Coenen, Michiel J J; Khoury, Tony; Crossley, Maxwell J; Hendriksen, Bas L M; Elemans, Johannes A A W; Speller, Sylvia

    2014-11-10

    Molecules of (5,10,15,20-tetraundecylporphyrinato)-copper(II) [(TUP)Cu] can self-assemble into four different polymorphs at the interface between highly oriented pyrolytic graphite and 1-octanoic acid. Scanning tunneling microscopy (STM) reveals that it is possible to combine the global control over monolayer structure, provided by the composition and concentration of the supernatant solution, with local control, from nanomanipulation by the STM tip. In the initially formed monolayer, with a polymorph composition governed by the concentration of (TUP)Cu in the supernatant solution, the exchange of molecules physisorbed at the solid/liquid interface with those in the liquid is very limited. By using a nanoshaving procedure at the tip, defects are created in the monolayer, and these serve as local manipulation sites to create domains of higher or lower molecular density, and to incorporate a second molecular species, (TUP)Co into the monolayer of (TUP)Cu. PMID:25146424

  10. Rapid Carbonation for Calcite from a Solid-Liquid-Gas System with an Imidazolium-Based Ionic Liquid

    PubMed Central

    Ibrahim, Abdul-Rauf; Vuningoma, Jean Bosco; Huang, Yan; Wang, Hongtao; Li, Jun

    2014-01-01

    Aqueous carbonation of Ca(OH)2 is a complex process that produces calcite with scalenohedral calcite phases and characterized by inadequate carbonate species for effective carbonation due to the poor dissolution of CO2 in water. Consequently, we report a solid-liquid-gas carbonation system with an ionic liquid (IL), 1-butyl-3-methylimidazolium bromide, in view of enhancing the reaction of CO2 with Ca(OH)2. The use of the IL increased the solubility of CO2 in the aqueous environment and enhanced the transport of the reactive species (Ca2+ and CO32?) and products. The presence of the IL also avoided the formation of the CaCO3 protective and passivation layer and ensured high carbonation yields, as well as the production of stoichiometric rhombohedral calcite phases in a short time. PMID:24968273

  11. Two-dimensional assemblies of banana-shaped liquid crystal molecules with short alkyl chains at solid/liquid interface.

    PubMed

    Li, Yibao; Asik, Jahimin; Yang, Yanlian; Rahman, Md Lutfor; Fan, Xiaolin; Wang, Chen

    2009-02-01

    Two-dimensional assemblies of a series of banana-shaped liquid crystal molecules with short alkyl chains, (LCn, n = 5, 6), are investigated at the solid/liquid interface on graphite surface by using scanning tunneling microscopy (STM) under ambient conditions. The high-resolution STM images of the LCn assemblies demonstrated a lamellae structure with bright bands and dark stripes, in which the alkyl chains of neighboring rows were either interdigitated or tail-to-tail due to the van der Waals interactions. The results in this paper are different with other reported banana-shaped liquid crystals, in which the core may play a dominant role in the self-assembly and the solvent molecules may also play a role in the assemblies. It may be helpful in understanding the assembly mechanism of banana-shaped liquid crystal molecules. PMID:19441480

  12. LES PROBLMATIQUES DE TRANSITION AUX NORMES

    E-print Network

    Paris-Sud XI, Université de

    LES PROBLÉMATIQUES DE TRANSITION AUX NORMES IFRS DES SOCIÉTÉS FONCIÈRES Eric TORT Expert-comptable certifié IFRS par les institutions (CSOEC, CNCC) Docteur en sciences de gestion, GREGOR de l'IAE de Paris 8 opérationnel, les problématiques du passage aux normes IFRS des sociétés foncières (évaluation des actifs

  13. ACCS AUX ESPACES COMMUNS ET GRANDES STRATGIES

    E-print Network

    Paris-Sud XI, Université de

    #12;ACCÈS AUX ESPACES COMMUNS ET GRANDES STRATÉGIES : VERS UN NOUVEAU JEU MONDIAL par Frédéric Ramel SCIENCES PO, CERI #12;ACCÈS AUX ESPACES COMMUNS ET GRANDES STRATÉGIES: VERS UN NOUVEAU JEU MONDIAL ARABES UNIS 9- ÉTUDIER LE RENSEIGNEMENT : ÉTAT DE L'ART ET PERSPECTIVES DE RECHERCHE 10- ENQUÊTE SUR LES

  14. Modulating the self-assembly of rigid "clicked" dendrimers at the solid-liquid interface by tuning non-covalent interactions between side groups.

    PubMed

    Cadeddu, Andrea; Ciesielski, Artur; El Malah, Tamer; Hecht, Stefan; Samorì, Paolo

    2011-10-14

    First generation poly(triazole-phenylene) dendrimers equipped with peripheral alkyl or carboxylic acid groups to engage in van der Waals and hydrogen-bonding interactions, respectively, assemble into distinct two-dimensional nano-structures at the solid-liquid interface as revealed by high resolution STM investigations. PMID:21869953

  15. Surface composition variation and high-vacuum performance of DLC/ILs solid-liquid lubricating coatings: Influence of space irradiation

    NASA Astrophysics Data System (ADS)

    Liu, Xiufang; Wang, Liping; Pu, Jibin; Xue, Qunji

    2012-08-01

    In this paper, we fabricated a DLC/ionic liquid (DLC/ILs) solid-liquid lubricating coating and investigated the effect of atomic oxygen (AO), ultraviolet (UV), proton and electron irradiations on composition, structure, morphology and tribological properties of the DLC/ILs solid-liquid lubricating coatings. A ground-based simulation facility was employed to carry out the irradiation experiments. X-ray photoelectron spectroscope (XPS), Raman spectra, and Fourier Transform Infrared Spectroscopy (FTIR) were used to analyzed the structure and composition changes of DLC film and IL lubricant before and after irradiations. The tribological behavior of the DLC/ILs solid-liquid lubricating coating before and after irradiations was investigated by a vacuum tribometer with the pressure of 10-5 Pa. The experimental results revealed that irradiations induced the structural changes, including oxidation, bond break and crosslinking reactions of DLC film and IL lubricant. The damage of proton and AO irradiations to lubricating materials were the most serious, and UV irradiation was the slightest. After irradiations, the friction coefficient of the solid-liquid lubricating coatings decreased (except for AO irradiation), but the disc wear rate increased compared with non-irradiation coatings.

  16. SOLID-LIQUID PHASE TRANSFER CATALYZED SYNTHESIS OF CINNAMYL ACETATE-KINETICS AND ANALYSIS OF FACTORS AFFECTING THE REACTION IN A BATCH REACTOR

    EPA Science Inventory

    The use of solid-liquid phase transfer catalysis has an advantage of carrying out reaction between two immiscible substrates, one in solid phase and the other in liquid phase, with high selectivity and at relatively low temperatures. In this study we investigated the synthesis ci...

  17. Hydrodynamic-induced enantiomeric enrichment of self-assemblies: Role of the solid-liquid interface in chiral nucleation and seeding

    NASA Astrophysics Data System (ADS)

    Raudino, Antonio; Pannuzzo, Martina

    2012-10-01

    A simple hydrodynamic model has been developed to explain the experimentally observed chirality selection in stirred solutions of self-assembling achiral dyes. Selection depends on the stirring direction: the dichroic signal reverses its shape in clockwise or anti-clockwise rotations. Our model investigates the possible role of the liquid-solid interface in nucleating, growing, and transferring to the bulk of chiral seeds. The nucleation step requires a double modulation of the hydrodynamic field exhibiting different velocity along two orthogonal axes. Under a series of restrictions, such a condition is easily met at the solid-liquid interface and it is dictated by the boundary conditions and geometry of stirring. In stagnant conditions, growing helices made-up of self-assembled achiral dyes have no chiral preference forming a racemic mixture that contains identical amount of right-handed (R) and left-handed (L) configurations. The application of a hydrodynamic torque (related to the velocity gradient and width of the helix) breaks down the original symmetry, a further velocity gradient perpendicular to the first one ensures, after averaging, a slightly different population of R and L conformations. The yields of the hydrodynamic-induced chirality excess are extremely tiny, hence the suggested mechanism is significant only if next chirality amplification processes are efficient. Again, hydrodynamics provides a tool for the detachment of weakly bound aggregates once they have reached a critical length. Aggregates are transported in the bulk where the ripening process goes to completion. The efficiency of the surface catalytic effect strongly depends on the aggregate-surface sticking energy, reaching a maximum at intermediate sticking energies (of order of 10 kT). Numerical estimates show that the proposed mechanism is rather efficient, giving rise to entatiomeric excesses near (but smaller than) those experimentally found.

  18. Molecular simulation of biomaterials and biomolecules at the solid-liquid interface

    E-print Network

    Kottmann, Stephen Thomas

    2008-01-01

    Biomaterials and biomineralization have been successfully utilized in a broad variety of technical applications. Properties of natural biopolymers, such as the ability to control the nucleation, growth, and organization ...

  19. Solid-liquid phase coexistence of alkali nitrates from molecular dynamics simulations.

    SciTech Connect

    Jayaraman, Saivenkataraman

    2010-03-01

    Alkali nitrate eutectic mixtures are finding application as industrial heat transfer fluids in concentrated solar power generation systems. An important property for such applications is the melting point, or phase coexistence temperature. We have computed melting points for lithium, sodium and potassium nitrate from molecular dynamics simulations using a recently developed method, which uses thermodynamic integration to compute the free energy difference between the solid and liquid phases. The computed melting point for NaNO3 was within 15K of its experimental value, while for LiNO3 and KNO3, the computed melting points were within 100K of the experimental values [4]. We are currently extending the approach to calculate melting temperatures for binary mixtures of lithium and sodium nitrate.

  20. Effect of antiscalant degradation on salt precipitation and solid\\/liquid separation of RO concentrate

    Microsoft Academic Search

    Lauren F. Greenlee; Fabrice Testa; Desmond F. Lawler; Benny D. Freeman; Philippe Moulin

    2011-01-01

    The key limitation to the application of reverse osmosis (RO) desalination on inland brackish waters is concentrate disposal. Due to precipitation of sparingly soluble salts (CaCO3, CaSO4, BaSO4, SrSO4), RO membrane recovery cannot be increased further; therefore, other strategies must be investigated. Antiscalants are often added to RO feed water to help prevent precipitation and increase RO recovery, but in

  1. The fabrication and properties of multifilamentary Nb/sub 3/Sn superconductors by the solid-liquid diffusion method

    SciTech Connect

    Nagata, M; Akiyama, Y.; Kawashima, M.; Kimura, Y.; Ohkura, K.; Okuda, S.; Umeda, M.; Watanabe, M.; Yamasaki, H.; Yokota, M.

    1982-01-01

    In this paper we describe the manufacturing process and properties of an Nb/sub 3/ Sn superconductor produced by the method of solid-liquid diffusion. The manufactured conductor used 93 wt.% Sn-7 wt.% Cu alloy cores surrounded by Nb. The Sn-Cu alloy became a liquid at the heat-treatment temperature of 690 degrees C. Tin-rich Nb compounds which formed initially during the heat treatment were rapidly transformed into an A15 Nb/sub 3/ Sn superconductor in 50-100 h. The multifilamentary conductor had the high overall critical current density of 1.5 x 10/sup 5/ A/cm/sup 2/ at 10 T. When the conductor was wound as a small coil it generated 11.6 T with a backup field of 10 T. An effort was made to enlarge the conductor size; a rectangular conductor of 2.5 mm x 5.0 mm was capable of carrying 3500 A at 10 T. We are currently constructing a large-scale 12 T magnet with an inner diameter of 400 mm and an outer diameter of 685 mm and a 7 T backup field with this conductor.

  2. Crystal growth kinetics in Lennard-Jones and Weeks-Chandler-Andersen systems along the solid-liquid coexistence line.

    PubMed

    Benjamin, Ronald; Horbach, Jürgen

    2015-07-01

    Kinetics of crystal-growth is investigated along the solid-liquid coexistence line for the (100), (110), and (111) orientations of the Lennard-Jones (LJ) and Weeks-Chandler-Andersen (WCA) fcc crystal-liquid interface, using non-equilibrium molecular dynamics simulations. A slowing down of the growth kinetics along the coexistence line is observed, which is due to the decrease of the melting enthalpy with increasing coexistence temperature and pressure. Other quantities such as the melting pressure and liquid self-diffusion coefficient have a comparatively lesser impact on the kinetic growth coefficient. Growth kinetics of the LJ and WCA potentials become similar at large values of the melting temperature and pressure, when both resemble a purely repulsive soft-sphere potential. Classical models of crystallization from the melt are in reasonable qualitative agreement with our simulation data. Finally, several one-phase empirical melting/freezing rules are studied with respect to their validity along the coexistence line. PMID:26156487

  3. Model for a solid-liquid stirred tank two-phase partitioning bioscrubber for the treatment of BTEX.

    PubMed

    Littlejohns, Jennifer V; McAuley, Kim B; Daugulis, Andrew J

    2010-03-15

    A dynamic mathematical model has been developed to predict the performance of a stirred tank, solid-liquid two-phase partitioning bioreactor (SL-TPPB) for the treatment of benzene, toluene, ethylbenzene and o-xylene (BTEX) contaminated gases. The SL-TPPB system consists of an aqueous phase containing a bacterial consortium and a solid phase of silicone rubber beads (10%; v/v) with a high affinity for BTEX compounds. The silicone rubber beads serve to sequester and release BTEX according to thermodynamic equilibrium, which increases mass transfer from the gas phase and reduces aqueous phase concentrations of these toxic compounds during fluctuating inlet loadings. The model was developed from mass balances on BTEX components in the gas, aqueous and polymer phases, and biomass in the aqueous phase. Dynamic experimental data from this system were used to fit model parameters and to assess the accuracy of the model. A detailed estimability analysis of model parameters and initial conditions was completed to identify uncertain parameters that are most influential for the model predictions and to determine the parameters and initial conditions that should be targeted for estimation using the dynamic data. It was found that the developed model, with estimated parameters and initial conditions, has the ability to predict experimental off-gas BTEX concentrations with reasonable accuracy, which are the outputs of greatest importance. PMID:19959280

  4. Synthesis of new phosphorus-containing (co)polyesters using solid-liquid phase transfer catalysis and product characterization.

    PubMed

    Iliescu, Smaranda; Augusti, Maite-Gyl; Fagadar-Cosma, Eugenia; Plesu, Nicoleta; Fagadar-Cosma, Gheorghe; Macarie, Lavinia; Popa, Adriana; Ilia, Gheorghe

    2012-01-01

    This paper is directed towards the development of safe, and thermally stable solid polymer electrolytes. Linear phosphorus-containing (co)polyesters are described, including their synthesis, thermal analysis, conductivity, and non-flammability. Polycondensation of phenylphosphonic dichloride (PPD) with poly(ethylene glycol) (PEG 12000) with and without bisphenol A (BA) was carried out using solid-liquid phase transfer catalysis. Potassium phosphate is used as base. Yields in the range of 85.0-88.0%, and inherent viscosities in the range of 0.32-0.58 dL/g were obtained. The polymers were characterized by gel permeation chromatography, FT-IR, (1)H- and (31)P-NMR spectroscopy and thermal analysis. Their flammability was investigated by measuring limiting oxygen index values. The polymers are flame retardants and begin to lose weight in the 190 °C-231 °C range. Solid phosphorus- containing (co)polyesters were complexed with lithium triflate and the resulting ionic conductivity was determined. Conductivities in the range of 10(-7)-10(-8) S cm(-1) were obtained. PMID:22850325

  5. Study on solid-liquid two-phase unsteady flow characteristics with different flow rates in screw centrifugal pump

    NASA Astrophysics Data System (ADS)

    Li, R. N.; Y Wang, H.; Han, W.; Ma, W.; Shen, Z. J.

    2013-12-01

    The screw centrifugal pump is used as an object, and the unsteady numerical simulation of solid-liquid two-phase flow is carried out under different flow rate conditions in one circle by choosing the two-phase flow of sand and water as medium, using the software FLUENT based on the URANS equations, combining with sliding mesh method, and choosing the Mixture multiphase flow model and the SIMPLE algorithm. The results show that, with the flow rate increasing, the change trends for the pressure on volute outlet are almost constant, the fluctuation trends of the impeller axial force have a little change, the pressure and the axial force turn to decrease on the whole, the radial force gradually increases when the impeller maximum radius passes by half a cycle near the volute outlet, and the radial force gradually decreases when the maximum radius passes by the other half a cycle in a rotation cycle. The distributions of the solid particles are very uneven under a small flow rate condition on the face. The solid particles under a big flow rate condition are distributed more evenly than the ones under a small flow rate condition on the back. The theoretical basis and reference are provided for improving its working performance.

  6. Toluene biodegradation in a solid/liquid system involving immobilized activated sludge and silicone oil as pollutant reservoir.

    PubMed

    Diz Castro, Manuel; Gómez-Díaz, Diego; Amrane, Abdeltif; Couvert, Annabelle

    2015-02-01

    A solid/liquid system involving activated sludge immobilized in an agar medium and a non-aqueous phase liquid containing the target pollutant has been considered to treat a model hydrophobic volatile organic compound, toluene. The positive impact of the use of a multiphase bioreactor is that the organic phase constitutes a pollutant reservoir and also helps to overcome possible pollutant toxicity. In addition and to overcome the drawbacks of the use of a solid organic phase (high pressure drop and low mass transfer) instead of a liquid organic phase, the considered solid phase was the aqueous. Consequently, silicone oil (polydimethylsiloxane) which showed its relevance for implementation in multiphase bioreactors was used. Promising results were observed from the analysis of toluene in the gaseous phase; for an initial amount of 2?g?L(-1) related to the organic phase, a v/v ratio of 0.5 of the organic phase to the aqueous agar phase, total toluene consumption was observed in about 9 days, leading to a global biodegradation rate of approximately 3.1?mg?L(-1)?h(-1), namely in the range of values previously observed in liquid/liquid systems. PMID:25187471

  7. Dynamique d'un laser a colorant a pompage synchrone avec cavite couplee et applications aux ondes terahertz breves et intenses

    NASA Astrophysics Data System (ADS)

    Baribault, Robert

    Nous presentons deux methodes de generation de battements de frequences terahertz pouvant servir a illuminer des antennes photoconductrices afin d'obtenir une emission a spectre etroit et une grande plage d'accordabilite dans l'infrarouge lointain (IRL). Nous discutons des differentes applications dans l'IRL, et presentons plusieurs techniques de generation d'IRL. Parmi ces methodes, nous choisissons celle qui depend de l'illumination incidente, basee sur un deplacement de charges dans un semi-conducteur soumis a une tension a ses bornes, l'antenne photoconductrice. Nous etudions l'emission d'ondes terahertz par cette antenne photoconductrice pour quatre types d'illumination, l'impulsion ultrabreve, l'impulsion ultrabreve modelee, le pseudo-battement par decalage d'impulsions avec glissement en frequence, et le battement. Nous presentons des resultats experimentaux d'illumination d'une antenne photoconductrice en silicium sur saphir endommage par radiation (rd-SOS) avec une impulsion breve et un battement. Un accroissement de l'efficacite est demontre pour le battement. Nous simulons la dynamique d'un laser a colorant a pompage synchrone (LACPS) afin de comprendre ses conditions optimales d'utilisation. Deux LACPS, pompes par le meme laser Nd:YAG, sont synchronises temporellement et spatialement et permettent d'obtenir un battement stable par le controle des delais optiques. Les durees a mi-hauteur des impulsions des deux LACPS doivent demeurer identiques en fonction de la longueur d'onde. La section efficace d'emission du milieu de gain est critique dans la dynamique de ce laser. La duree a mi-hauteur de l'impulsion varie peu avec la section efficace d'emission. Pour controler les fluctuations dues a l'emission spontanee, on ajoute une cavite couplee qui minimise l'effet de l'emission spontanee dans la dynamique du LACPS. Nous montrons les battements obtenus avec deux LACPS, de 0.5 THz et 18 THz, dont deux, a 0.85 THz et 9.36 THz sont amplifies jusqu'a une energie d'impulsion de l'ordre du millijoule. En conclusion, nous proposons une modification au systeme de generation de battement qui facilite l'utilisation du montage. Nous presentons une methode alternative de stabiliser la forme temporelle des impulsions du LACPS sans la cavite couplee. Nous presentons egalement une nouvelle approche d'illumination d'une antenne photoconductrice avec un battement avec un glissement en frequence.

  8. Direct imaging of complex nano- to microscale interfaces involving solid, liquid, and gas phases.

    PubMed

    Rykaczewski, Konrad; Landin, Trevan; Walker, Marlon L; Scott, John Henry J; Varanasi, Kripa K

    2012-10-23

    Surfaces with special wetting properties not only can efficiently repel or attract liquids such as water and oils but also can prevent formation of biofilms, ice, and clathrate hydrates. Predicting the wetting properties of these special surfaces requires detailed knowledge of the composition and geometry of the interfacial region between the droplet and the underlying substrate. In this work we introduce a 3D quantitative method for direct nanoscale visualization of such interfaces. Specifically, we demonstrate direct nano- to microscale imaging of complex fluidic interfaces using cryostabilization in combination with cryogenic focused ion beam milling and SEM imaging. We show that application of this method yields quantitative information about the interfacial geometry of water condensate on superhydrophilic, superhydrophobic, and lubricant-impregnated surfaces with previously unattainable nanoscale resolution. This type of information is crucial to a fundamental understanding as well as the design of surfaces with special wetting properties. PMID:23020195

  9. Thermodynamic and rheological properties of solid-liquid systems in coal processing. Quarterly technical report, March 1, 1992--May 31, 1992

    SciTech Connect

    Kabadi, V.N.; Ilias, S.

    1992-12-31

    In this report we present two data sets that have been compiled to assist in the model developments for solid-liquid equilibria and viscosities of coal derived systems. The first one is on vapor pressures of solid aromatics and the second one consists of viscosities of pure model compounds and some mixtures. These databanks are ready for usage in model development and are summarized in Tables 1 and 2. Literature is being searched to compile similar data for high pressure liquid compressibilities, liquid and solid heat capacities and solid-liquid equilibria for model compound systems. Literature search is also containing to investigate available viscosity models. Once this is completed a few models will be selected for evaluation and consideration as candidates for extension to coal liquids.

  10. Processing of diamond particle dispersed aluminum matrix composites in continuous solid–liquid co-existent state by SPS and their thermal properties

    Microsoft Academic Search

    Kiyoshi Mizuuchi; Kanryu Inoue; Yasuyuki Agari; Yoshiaki Morisada; Masami Sugioka; Motohiro Tanaka; Takashi Takeuchi; Jun-ichi Tani; Masakazu Kawahara; Yukio Makino

    2011-01-01

    Diamond-particle-dispersed-aluminum (Al) matrix composites were fabricated in a unique fabrication method where continuous solid–liquid co-existent state of the powder mixture of diamond, pure Al and Al–5mass%Si alloy was designed during spark plasma sintering (SPS) process. Microstructures and thermal properties of the composites fabricated in such a way were investigated. The composites can be well consolidated in the temperature range between

  11. Form-stable paraffin\\/high density polyethylene composites as solid–liquid phase change material for thermal energy storage: preparation and thermal properties

    Microsoft Academic Search

    Ahmet Sar?

    2004-01-01

    This paper deals with the preparation of paraffin\\/high density polyethylene (HDPE) composites as form-stable, solid–liquid phase change material (PCM) for thermal energy storage and with determination of their thermal properties. In such a composite, the paraffin (P) serves as a latent heat storage material and the HDPE acts as a supporting material, which prevents leakage of the melted paraffin because

  12. X-ray and neutron surface scattering for studying lipidrpolymer assemblies at the air)liquid and solid)liquid interfaces

    Microsoft Academic Search

    Jaroslaw Majewski; Tonya L. Kuhl; Joyce Y. Wong; Gregory S. Smith

    Simple mono- and bilayers, built of amphiphilic molecules and prepared at air)liquid or solid)liquid interfaces, can be used as models to study such effects as water penetration, hydrocarbon chain packing, and structural changes due to head group modification. In the paper, we will discuss neutron and X-ray reflectometry and grazing incidence X-ray diffraction techniques used to explore structures of such

  13. Vapour–liquid equilibria, azeotropic data, excess enthalpies, activity coefficients at infinite dilution and solid–liquid equilibria for binary alcohol–ketone systems

    Microsoft Academic Search

    Rima Abbas; Jürgen Gmehling

    2008-01-01

    Isothermal vapour–liquid equilibria (VLE), solid–liquid equilibria and excess enthalpies have been measured for the systems cyclohexanone+cyclohexanol and 2-octanone+1-hexanol. Additionally in this paper binary azeotropic data at different pressures for 1-pentanol+2-heptanone and 1-hexanol+2-octanone have been determined with the help of a wire band column. Furthermore activity coefficients at infinite dilution for methanol, ethanol, 1-butanol and 1-propanol in 2-octanone at different temperatures

  14. Guanosine-based hydrogen-bonded 2D scaffolds: metal-free formation of G-quartet and G-ribbon architectures at the solid/liquid interface.

    PubMed

    Garah, Mohamed El; Perone, Rosaria C; Bonilla, Alejandro Santana; Haar, Sébastien; Campitiello, Marilena; Gutierrez, Rafael; Cuniberti, Gianaurelio; Masiero, Stefano; Ciesielski, Artur; Samorì, Paolo

    2015-07-25

    We report on the synthesis and self-assembly of three novel lipophilic guanosine derivatives exposing a ferrocene moiety in the C(5') position of the sugar unit. Their self-association in solution, and at the solid/liquid interface, can be tuned by varying the size and nature of the C(8)-substituent, leading to the generation of either G-ribbons, lamellar G-dimer based arrays or the G4 cation-free architectures. PMID:26102583

  15. Former aux comptences TIC et aux comptences informationnelles : des objectifs intimement lis en formation

    E-print Network

    Paris-Sud XI, Université de

    Former aux compétences TIC et aux compétences informationnelles : des objectifs intimement liés en.dumouchel@umontreal.ca Université de Montréal Résumé: Pour mieux comprendre la forte relation qui existe entre les compétences TIC enchaînons avec une vue d'ensemble des études empiriques sur le niveau des compétences TIC et

  16. Using "Tender" X-ray Ambient Pressure X-Ray Photoelectron Spectroscopy as A Direct Probe of Solid-Liquid Interface.

    PubMed

    Axnanda, Stephanus; Crumlin, Ethan J; Mao, Baohua; Rani, Sana; Chang, Rui; Karlsson, Patrik G; Edwards, Mårten O M; Lundqvist, Måns; Moberg, Robert; Ross, Phil; Hussain, Zahid; Liu, Zhi

    2015-01-01

    We report a new method to probe the solid-liquid interface through the use of a thin liquid layer on a solid surface. An ambient pressure XPS (AP-XPS) endstation that is capable of detecting high kinetic energy photoelectrons (7?keV) at a pressure up to 110?Torr has been constructed and commissioned. Additionally, we have deployed a "dip &pull" method to create a stable nanometers-thick aqueous electrolyte on platinum working electrode surface. Combining the newly constructed AP-XPS system, "dip &pull" approach, with a "tender" X-ray synchrotron source (2?keV-7?keV), we are able to access the interface between liquid and solid dense phases with photoelectrons and directly probe important phenomena occurring at the narrow solid-liquid interface region in an electrochemical system. Using this approach, we have performed electrochemical oxidation of the Pt electrode at an oxygen evolution reaction (OER) potential. Under this potential, we observe the formation of both Pt(2+) and Pt(4+) interfacial species on the Pt working electrode in situ. We believe this thin-film approach and the use of "tender" AP-XPS highlighted in this study is an innovative new approach to probe this key solid-liquid interface region of electrochemistry. PMID:25950241

  17. Using “Tender” x-ray ambient pressure x-Ray photoelectron spectroscopy as a direct probe of solid-liquid interface

    DOE PAGESBeta

    Axnanda, Stephanus; Crumlin, Ethan J.; Mao, Baohua; Rani, Sana; Chang, Rui; Karlsson, Patrik G.; Edwards, Mårten O. M.; Lundqvist, Måns; Moberg, Robert; Ross, Phil; et al

    2015-05-07

    We report a new method to probe the solid-liquid interface through the use of a thin liquid layer on a solid surface. An ambient pressure XPS (AP-XPS) endstation that is capable of detecting high kinetic energy photoelectrons (7 keV) at a pressure up to 110 Torr has been constructed and commissioned. Additionally, we have deployed a “dip & pull” method to create a stable nanometers-thick aqueous electrolyte on platinum working electrode surface. Combining the newly constructed AP-XPS system, “dip & pull” approach, with a “tender” X-ray synchrotron source (2 keV–7 keV), we are able to access the interface between liquidmore »and solid dense phases with photoelectrons and directly probe important phenomena occurring at the narrow solid-liquid interface region in an electrochemical system. Using this approach, we have performed electrochemical oxidation of the Pt electrode at an oxygen evolution reaction (OER) potential. Under this potential, we observe the formation of both Pt²? and Pt?? interfacial species on the Pt working electrode in situ. We believe this thin-film approach and the use of “tender” AP-XPS highlighted in this study is an innovative new approach to probe this key solid-liquid interface region of electrochemistry.« less

  18. Using “Tender” X-ray Ambient Pressure X-Ray Photoelectron Spectroscopy as A Direct Probe of Solid-Liquid Interface

    NASA Astrophysics Data System (ADS)

    Axnanda, Stephanus; Crumlin, Ethan J.; Mao, Baohua; Rani, Sana; Chang, Rui; Karlsson, Patrik G.; Edwards, Mårten O. M.; Lundqvist, Måns; Moberg, Robert; Ross, Phil; Hussain, Zahid; Liu, Zhi

    2015-05-01

    We report a new method to probe the solid-liquid interface through the use of a thin liquid layer on a solid surface. An ambient pressure XPS (AP-XPS) endstation that is capable of detecting high kinetic energy photoelectrons (7?keV) at a pressure up to 110?Torr has been constructed and commissioned. Additionally, we have deployed a “dip & pull” method to create a stable nanometers-thick aqueous electrolyte on platinum working electrode surface. Combining the newly constructed AP-XPS system, “dip & pull” approach, with a “tender” X-ray synchrotron source (2?keV–7?keV), we are able to access the interface between liquid and solid dense phases with photoelectrons and directly probe important phenomena occurring at the narrow solid-liquid interface region in an electrochemical system. Using this approach, we have performed electrochemical oxidation of the Pt electrode at an oxygen evolution reaction (OER) potential. Under this potential, we observe the formation of both Pt2+ and Pt4+ interfacial species on the Pt working electrode in situ. We believe this thin-film approach and the use of “tender” AP-XPS highlighted in this study is an innovative new approach to probe this key solid-liquid interface region of electrochemistry.

  19. Using “Tender” x-ray ambient pressure x-Ray photoelectron spectroscopy as a direct probe of solid-liquid interface

    DOE PAGESBeta

    Axnanda, Stephanus [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Crumlin, Ethan J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mao, Baohua [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chinese Academy of Sciences, Shanghai (Republic of China); Rani, Sana [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chang, Rui [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chinese Academy of Sciences, Shanghai (Republic of China); Karlsson, Patrik G. [VG Scienta,Uppsala (Sweden); Edwards, Mårten O. M. [VG Scienta,Uppsala (Sweden); Lundqvist, Måns [VG Scienta,Uppsala (Sweden); Moberg, Robert [VG Scienta,Uppsala (Sweden); Ross, Phil [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hussain, Zahid [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Liu, Zhi [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chinese Academy of Sciences, Shanghai (Republic of China); Shanghai Tech Univ., Shanghai (China)

    2015-05-07

    We report a new method to probe the solid-liquid interface through the use of a thin liquid layer on a solid surface. An ambient pressure XPS (AP-XPS) endstation that is capable of detecting high kinetic energy photoelectrons (7 keV) at a pressure up to 110 Torr has been constructed and commissioned. Additionally, we have deployed a “dip & pull” method to create a stable nanometers-thick aqueous electrolyte on platinum working electrode surface. Combining the newly constructed AP-XPS system, “dip & pull” approach, with a “tender” X-ray synchrotron source (2 keV–7 keV), we are able to access the interface between liquid and solid dense phases with photoelectrons and directly probe important phenomena occurring at the narrow solid-liquid interface region in an electrochemical system. Using this approach, we have performed electrochemical oxidation of the Pt electrode at an oxygen evolution reaction (OER) potential. Under this potential, we observe the formation of both Pt²? and Pt?? interfacial species on the Pt working electrode in situ. We believe this thin-film approach and the use of “tender” AP-XPS highlighted in this study is an innovative new approach to probe this key solid-liquid interface region of electrochemistry.

  20. Thermodynamic and rheological properties of solid-liquid systems in coal processing. Final technical report

    SciTech Connect

    Kabadi, V.N.

    1995-06-30

    The work on this project was initiated on September 1, 1991. The project consisted of two different tasks: (1) Development of a model to compute viscosities of coal derived liquids, and (2) Investigate new models for estimation of thermodynamic properties of solid and liquid compounds of the type that exist in coal, or are encountered during coal processing. As for task 1, a model for viscosity computation of coal model compound liquids and coal derived liquids has been developed. The detailed model is presented in this report. Two papers, the first describing the pure liquid model and the second one discussing the application to coal derived liquids, are expected to be published in Energy & Fuels shortly. Marginal progress is reported on task 2. Literature review for this work included compilation of a number of data sets, critical investigation of data measurement techniques available in the literature, investigation of models for liquid and solid phase thermodynamic computations. During the preliminary stages it was discovered that for development of a liquid or solid state equation of state, accurate predictive models for a number of saturation properties, such as, liquid and solid vapor pressures, saturated liquid and solid volumes, heat capacities of liquids and solids at saturation, etc. Most the remaining time on this task was spent in developing predictive correlations for vapor pressures and saturated liquid volumes of organic liquids in general and coal model liquids in particular. All these developments are discussed in this report. Some recommendations for future direction of research in this area are also listed.

  1. Atomic Force Microscopy of Physical and Chemical Processes at the Solid-Liquid Interface

    NASA Astrophysics Data System (ADS)

    Manne, Srinivas

    This thesis describes research using atomic force microscopy (AFM) to study dynamics of solid surfaces in contact with liquids. Specifically, three applications are described: electrochemistry (Chapters 1-3), crystal growth (Chapters 4 and 5), and biomineralization (Chapter 6). Chapter 1 shows the feasibility of using AFM to image metal atoms in liquid, which sets the stage for high -resolution electrochemistry. Chapter 2 describes methods to convert the standard AFM liquid cell into an electrochemical cell and shows images of a gold electrode during oxidation/reduction cycling. Chapter 3 follows an electroplating cycle, wherein copper is deposited from electrolyte onto a gold electrode and then stripped off. The surface lattice is shown to change from that of bulk gold to bulk copper during plating, and back to bulk gold after stripping. Moreover, the first monolayer of copper--which deposits at an "underpotential", before the bulk deposition--is shown to have a lattice which differs from the bulk and is electrolyte dependent. Like electrochemistry, the study of crystal growth is also perfectly suited to a surface technique such as AFM. AFM makes it possible to image "elemental steps" (i.e., steps one unit cell thick) on a single crystal and quantify their motion during growth and dissolution. This is illustrated for the inorganic crystal calcite (Chapter 4) and the more fragile organic crystal L-leucine (Chapter 5). In both cases it is shown that step speed is independent of spacing between steps, indicating that motion occurs by direct interaction of the step-site molecules with the solvent. Chapter 5 also describes techniques for growing and imaging organic crystals. Living organisms also use crystal growth, modified by inorganic and organic additives, to grow mineralized structures such as bones, teeth and seashells. In Chapter 6, AFM reveals the three-dimensional structure of the nacreous or pearly layer of mollusc shells by slowly etching away successive mineral layers (in weak acid) while imaging. Etch figures on the mineral (aragonite) are correlated with crystallographic directions, revealing overall crystalline order on large scans. In bivalves, this order is observed both laterally across the layer and vertically between layers, whereas gastropod nacre is observed to be ordered only vertically.

  2. Order-parameter-aided temperature-accelerated sampling for the exploration of crystal polymorphism and solid-liquid phase transitions

    PubMed Central

    Yu, Tang-Qing; Chen, Pei-Yang; Chen, Ming; Samanta, Amit; Vanden-Eijnden, Eric; Tuckerman, Mark

    2014-01-01

    The problem of predicting polymorphism in atomic and molecular crystals constitutes a significant challenge both experimentally and theoretically. From the theoretical viewpoint, polymorphism prediction falls into the general class of problems characterized by an underlying rough energy landscape, and consequently, free energy based enhanced sampling approaches can be brought to bear on the problem. In this paper, we build on a scheme previously introduced by two of the authors in which the lengths and angles of the supercell are targeted for enhanced sampling via temperature accelerated adiabatic free energy dynamics [T. Q. Yu and M. E. Tuckerman, Phys. Rev. Lett. 107, 015701 (2011)]. Here, that framework is expanded to include general order parameters that distinguish different crystalline arrangements as target collective variables for enhanced sampling. The resulting free energy surface, being of quite high dimension, is nontrivial to reconstruct, and we discuss one particular strategy for performing the free energy analysis. The method is applied to the study of polymorphism in xenon crystals at high pressure and temperature using the Steinhardt order parameters without and with the supercell included in the set of collective variables. The expected fcc and bcc structures are obtained, and when the supercell parameters are included as collective variables, we also find several new structures, including fcc states with hcp stacking faults. We also apply the new method to the solid-liquid phase transition in copper at 1300 K using the same Steinhardt order parameters. Our method is able to melt and refreeze the system repeatedly, and the free energy profile can be obtained with high efficiency. PMID:24907992

  3. Protein allostery at the solid-liquid interface: endoglucanase attachment to cellulose affects glucan clenching in the binding cleft.

    PubMed

    Lin, Yuchun; Silvestre-Ryan, Jordi; Himmel, Michael E; Crowley, Michael F; Beckham, Gregg T; Chu, Jhih-Wei

    2011-10-19

    At phase boundaries, physical activities of enzymes such as substrate complexation play critical roles in driving biocatalysis. A prominent example is the cellulase cocktails secreted by fungi and bacteria for deconstructing crystalline cellulose in biomass into soluble sugars. At interfaces, molecular mechanisms of the physical steps in biocatalysis remain elusive due to the difficulties of characterizing protein action with high temporal and spatial resolution. Here, we focus on endoglucanase I (Cel7B) from the fungus Trichoderma reesei that hydrolyzes glycosidic bonds on cellulose randomly. We employ all-atom molecular dynamics (MD) simulations to elucidate the interactions of the catalytic domain (CD) of Cel7B with a cellulose microfibril before and after complexing a glucan chain in the binding cleft. The calculated mechanical coupling networks in Cel7B-glucan and Cel7B-microfibril complexes reveal a previously unresolved allosteric coupling at the solid-liquid interface: attachment of the Cel7B CD to the cellulose surface affects glucan chain clenching in the binding cleft. Alternative loop segments of the Cel7B CD were found to affix to intact or defective surface structures on the microfibril, depending on the complexation state. From a multiple sequence alignment, residues in surface-affixing segments show strong conservation, highlighting the functional importance of the physical activities that they facilitate. Surface-affixing residues also demonstrate significant sequence correlation with active-site residues, revealing the functional connection between complexation and hydrolysis. Analysis of the Cel7B CD exemplifies that the mechanical coupling networks calculated from atomistic MD simulations can be used to capture the conservation and correlation in sequence alignment. PMID:21877736

  4. Spectrofluorimetric determination of melatonin in kernels of four different Pistacia varieties after ultrasound-assisted solid-liquid extraction

    NASA Astrophysics Data System (ADS)

    Oladi, Elham; Mohamadi, Maryam; Shamspur, Tayebeh; Mostafavi, Ali

    2014-11-01

    Melatonin is normally consumed to regulate the body's biological cycle. However it also has therapeutic properties, such as anti-tumor, anti-aging and protects the immune system. There are some reports on the presence of melatonin in edible kernels such as walnuts, but the extraction of melatonin from pistachio kernels is reported here for the first time. For this, the methanolic extract of pistachio kernels was exposed to gas chromatography/mass spectrometry analysis which confirmed the presence of melatonin. A fluorescence-based method was applied for the determination of melatonin in different extracts. When excited at ? = 275 nm, the fluorescence emission intensity of melatonin was measured at ? = 366 nm. Ultrasound-assisted solid-liquid extraction was used for the extraction of melatonin from pistachio kernels prior to fluorimetric determination. To achieve the highest extraction recovery, the main parameters affecting the extraction efficiency such as extracting solvent type and volume, temperature, sonication time and pH were evaluated. Under the optimized conditions, a linear dependence of fluorescence intensity on melatonin concentration was observed in the range of 0.0040-0.160 ?g mL-1, with a detection limit of 0.0036 ?g mL-1. This method was applied successfully for measuring and comparing the melatonin content in the kernels of four different varieties of Pistacia including Ahmad Aghaei, Akbari, Kalle Qouchi and Fandoghi. In addition, the results obtained were compared with those obtained using GC/MS. A good agreement was observed indicating the reliability of the proposed method.

  5. Order-parameter-aided temperature-accelerated sampling for the exploration of crystal polymorphism and solid-liquid phase transitions

    SciTech Connect

    Yu, Tang-Qing, E-mail: tangqing.yu@nyu.edu; Vanden-Eijnden, Eric, E-mail: eve2@cims.nyu.edu [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States); Chen, Pei-Yang; Chen, Ming [Department of Chemistry, New York University, New York, New York 10003 (United States); Samanta, Amit [Program in Applied and Computational Mathematics, Princeton University, Princeton, New Jersey 08544, USA and Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Tuckerman, Mark, E-mail: mark.tuckerman@nyu.edu [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States); Department of Chemistry, New York University, New York, New York 10003 (United States); NYU-ECNU Center for Computational Chemistry at NYU Shanghai, Shanghai 200062 (China)

    2014-06-07

    The problem of predicting polymorphism in atomic and molecular crystals constitutes a significant challenge both experimentally and theoretically. From the theoretical viewpoint, polymorphism prediction falls into the general class of problems characterized by an underlying rough energy landscape, and consequently, free energy based enhanced sampling approaches can be brought to bear on the problem. In this paper, we build on a scheme previously introduced by two of the authors in which the lengths and angles of the supercell are targeted for enhanced sampling via temperature accelerated adiabatic free energy dynamics [T. Q. Yu and M. E. Tuckerman, Phys. Rev. Lett. 107, 015701 (2011)]. Here, that framework is expanded to include general order parameters that distinguish different crystalline arrangements as target collective variables for enhanced sampling. The resulting free energy surface, being of quite high dimension, is nontrivial to reconstruct, and we discuss one particular strategy for performing the free energy analysis. The method is applied to the study of polymorphism in xenon crystals at high pressure and temperature using the Steinhardt order parameters without and with the supercell included in the set of collective variables. The expected fcc and bcc structures are obtained, and when the supercell parameters are included as collective variables, we also find several new structures, including fcc states with hcp stacking faults. We also apply the new method to the solid-liquid phase transition in copper at 1300 K using the same Steinhardt order parameters. Our method is able to melt and refreeze the system repeatedly, and the free energy profile can be obtained with high efficiency.

  6. Solid-liquid separation method governs the in vitro bioaccessibility of metals in contaminated soil-like test materials.

    PubMed

    Laird, Brian D; Weiseth, Blake; Packull-McCormick, Sara R; Peak, Derek; Dodd, Matt; Siciliano, Steven D

    2015-09-01

    An in vitro gastrointestinal model was used to explore the role of solid-liquid separation method on the bioaccessibility of trace elements in a smelter-impacted soil (NIST-2711) from Helena, MT and a mine overburden from an open-pit gold and silver mine in Mount Nansen, YK (YK-OVB). Separation methods studied included centrifugation (5000g, 12000g), syringe microfiltration (0.45?m), and ultrafiltration (1000kDa, 50kDa, 30kDa, 10kDa, 3kDa). Results indicated that the use of syringe microfiltration generally yields the same bioaccessibility as the use of centrifugation and that the speed of centrifugation does not typically affect metal bioaccessibility. However, ultrafiltration consistently yields a significantly lower bioaccessibility than the use of centrifugation and syringe microfiltration. There are rarely any differences between bioaccessibility estimates generated using a low-resistance (1000kDa) and a high-resistance (3kDa) ultrafiltration membrane; therefore, under the in vitro gastrointestinal conditions modeled herein, negligible quantities of trace elements are complexed to small molecules between 3 and 1000kDa. The primary exceptions to these trends were observed for Pb in NIST-2711 (5000g>12000g>0.45?m>ultrafiltration) and for Tl in NIST-2711 and YK-OVB (5000g?12000g>0.45?m>ultrafiltration). These results provide valuable information to researchers attempting to expand the use of in vitro bioaccessibility beyond soil Pb and As. PMID:25600322

  7. Spectrofluorimetric determination of melatonin in kernels of four different Pistacia varieties after ultrasound-assisted solid-liquid extraction.

    PubMed

    Oladi, Elham; Mohamadi, Maryam; Shamspur, Tayebeh; Mostafavi, Ali

    2014-11-11

    Melatonin is normally consumed to regulate the body's biological cycle. However it also has therapeutic properties, such as anti-tumor, anti-aging and protects the immune system. There are some reports on the presence of melatonin in edible kernels such as walnuts, but the extraction of melatonin from pistachio kernels is reported here for the first time. For this, the methanolic extract of pistachio kernels was exposed to gas chromatography/mass spectrometry analysis which confirmed the presence of melatonin. A fluorescence-based method was applied for the determination of melatonin in different extracts. When excited at ?=275 nm, the fluorescence emission intensity of melatonin was measured at ?=366 nm. Ultrasound-assisted solid-liquid extraction was used for the extraction of melatonin from pistachio kernels prior to fluorimetric determination. To achieve the highest extraction recovery, the main parameters affecting the extraction efficiency such as extracting solvent type and volume, temperature, sonication time and pH were evaluated. Under the optimized conditions, a linear dependence of fluorescence intensity on melatonin concentration was observed in the range of 0.0040-0.160 ?g mL(-1), with a detection limit of 0.0036 ?g mL(-1). This method was applied successfully for measuring and comparing the melatonin content in the kernels of four different varieties of Pistacia including Ahmad Aghaei, Akbari, Kalle Qouchi and Fandoghi. In addition, the results obtained were compared with those obtained using GC/MS. A good agreement was observed indicating the reliability of the proposed method. PMID:24878439

  8. Ultra-fast liquid chromatography with tandem mass spectrometry determination of ochratoxin A in traditional Chinese medicines based on vortex-assisted solid-liquid microextraction and aptamer-affinity column clean-up.

    PubMed

    Yang, Xihui; Hu, Yichen; Kong, Weijun; Chu, Xianfeng; Yang, Meihua; Zhao, Ming; Ouyang, Zhen

    2014-11-01

    A rapid, selective, and sensitive ultra-fast liquid chromatography with tandem mass spectrometry method was developed for the determination of ochratoxin A in traditional Chinese medicines based on vortex-assisted solid-liquid microextraction and aptamer-affinity column clean-up. Through optimizing the sample pretreatment procedures and chromatographic conditions, good linearity (r(2) ? 0.9993), low limit of detection (0.5-0.8 ?g/kg), and satisfactory recovery (83.54-94.44%) expressed the good reliability and applicability of the established method in various traditional Chinese medicines. Moreover, the aptamer-affinity column, prepared in-house, showed an excellent feasibility owing to its specific identification of ochratoxin A in various kinds of selected traditional Chinese medicines. The maximum adsorption amount and applicability value were 188.96 ± 10.56 ng and 72.3%, respectively. The matrix effects were effectively eliminated, especially for m/z 404.2?358.0 of ochratoxin A. The application of the developed method for screening the natural contamination levels of ochratoxin A in 25 random traditional Chinese medicines on the market in China indicated that only eight samples were contaminated with low levels below the legal limit (5.0 ?g/kg) set by the European Union. This study provided a preferred choice for the rapid and accurate monitoring of ochratoxin A in complex matrices. PMID:25195673

  9. Aux\\/IAA Proteins Contain a Potent Transcriptional Repression Domain

    Microsoft Academic Search

    Shiv B. Tiwari; Gretchen Hagen; Tom J. Guilfoyle

    2004-01-01

    Aux\\/IAA proteins are short-lived nuclear proteins that repress expression of primary\\/early auxin response genes in protoplast transfection assays. Repression is thought to result from Aux\\/IAA proteins dimerizing with auxin response factor (ARF) transcriptional activators that reside on auxin-responsive promoter elements, referred to as AuxREs. Most Aux\\/IAA proteins contain four conserved domains, designated domains I, II, III, and IV. Domain II

  10. Jacquelin Charbonnel -ANF Mathrice -Angers 2012 Introduction aux expressions rgulires 1/21 Introduction aux expressions rgulires

    E-print Network

    Menichi, Luc

    Jacquelin Charbonnel - ANF Mathrice - Angers 2012 Introduction aux expressions régulières 1 Mathrice - Angers, mai 2012 #12;Jacquelin Charbonnel - ANF Mathrice - Angers 2012 Introduction aux expressions régulières 2/21 RE POSIX #12;Jacquelin Charbonnel - ANF Mathrice - Angers 2012 Introduction aux

  11. PENTOM 2005 Maintenance prdictive applique aux

    E-print Network

    Boyer, Edmond

    the signature of a health of a board. MOTS CLES : Maintenance proactive, diagnostic, surveillance, avionique KEYWORDS: Proactive maintenance, diagnostic, monitoring, avionics hal-00185497,version1-6Nov2007 ManuscritPENTOM 2005 Maintenance prédictive appliquée aux systèmes électroniques embarqués Samir Ghelam

  12. Prix Louis Dallves Appel aux candidatures

    E-print Network

    Rochaix, Jean-David

    Prix Louis Dallèves Appel aux candidatures Le Prix Louis Dallèves 2014 est mis au concours. Il est) Montant du prix : au maximum Frs 4000 (le montant est fixé par la Commission du Prix Louis Dallèves dividende le montant qui a permis d'instituer le Prix Louis Dallèves. Informée de ce geste émouvant, la

  13. Comparison of lab-scale and pilot-scale hybrid anaerobic solid–liquid systems operated in batch and semi-continuous modes

    Microsoft Academic Search

    J. Y. Wang; H. Zhang; O. Stabnikova; J. H. Tay

    2005-01-01

    The hybrid anaerobic solid–liquid (HASL) system was developed for food waste bioconversion. Lab-scale and pilot-scale HASL systems were operated in batch and semi-continuous modes. High efficiencies for conversion of food waste into biogas were shown for both the lab-scale and pilot-scale HASL systems. Semi-continuous mode of HASL system was more effective than batch process. Methane production was 0.49ll?1day?1 and 0.71ll?1day?1

  14. Etude Experimentale et Modelisation des Equilibres Solide—Liquide du Systeme Binaire H 2 O—UO 2 (NO 3 ) 2

    Microsoft Academic Search

    R. Tenu; S. Gentil; S. Baudu; J. J. Counioux

    1999-01-01

    The binary system H2O—UO2(NO3)2 was studied by solubility measurements and constant heat flow thermal analysis. Temperature and composition of the eutectic transformation between ice and uranyl nitrate hexahydrate were accurately defined. A new hydrate with 24 molecules of water decomposes at –21°C according to the peritectoid reaction2(NO3)2·24H2O> 2(NO3)2·6H2O> + 182O>The quasi-ideal model was applied to the solid—liquid equilibria, using the

  15. Investigating the influence of production conditions on the energy distribution between the solid, liquid and gaseous products of slow pyrolysis

    NASA Astrophysics Data System (ADS)

    Crombie, Kyle; Masek, Ondrej

    2013-04-01

    Slow pyrolysis is a well established technology for converting biomass into a more stable form of carbon (biochar) while also producing energy rich by-products of bio-oil and syngas. Biochar is the porous, carbonaceous material produced by thermo-chemical treatment of organic materials in an oxygen-limited environment. Biochar can be incorporated into soils to improve soil fertility, reduce greenhouse gas emissions as well as provide long term storage of carbon or alternatively it can also provide additional energy to a pyrolysis system through combustion. Biochar production conditions have a significant influence on the yield as well as physiochemical and functional properties of the final pyrolysis products, resulting in a selection process aimed towards either agricultural benefits and carbon mitigation or heat/energy generation. This work aimed to investigate the effect of temperature, residence time and gas flow rate on the product energy distribution as well as the physical, chemical and soil functional properties of biochar, in order to optimise conditions best suited to maximise both energy value and agronomic benefit. Biochar samples were produced from wood pellets (WP) and straw pellets (SP) at two temperatures (350 and 650oC), with three residence times (10, 20 and 40 minutes) and three carrier gas flow rates (0, 0.3 and 0.6 L min-1). The energy balance of the system was determined through the calorimetric analysis of biochar and bio-oil, while the higher heating value for the syngas was calculated from the gas composition measured via mass spectroscopy. Biochar was also analysed for the physiochemical properties of proximate analysis and ultimate analysis as well as the functional property of environmentally stable carbon (C) content. As expected the yield of biochar decreased with increasing temperature resulting in elevated yields of liquid and gas fractions. Increased temperature also resulted in higher values of fixed C, total C, stable C and calorific value due to the increased emission of volatiles. The higher heating value for the syngas was also shown to increase with temperature due to greater release of combustible gas species at higher temperatures. The impact of residence time and gas flow rate were not as clear as for temperature but still demonstrated decreasing biochar yields as the respective parameters were increased. However the greatest impact occurred at 350oC and diminished when temperature was increased to 650oC. An understanding of the influence that production conditions have on the long term stability of biochar as well as the energy content of the solid, liquid and gas fractions obtained from pyrolysis is critical towards the development of specifically engineered biochar to deliver a specific function be it for agricultural use, carbon storage, energy generation or combinations of the three.

  16. Determination of the Solid/Liquid Interface Shape and Resultant Radial Homogeneity in Directionally Solidified Hg(0.89)Mn(0.11)Te

    NASA Technical Reports Server (NTRS)

    Price, M. W.; Scripa, R. N.; Lehoczky, S. L.; Szofran, F. R.; Hanson, B.

    1999-01-01

    Directional solidification and interrupted directional solidification experiments were used to determine tile shape of the solid/liquid interface and the resultant radial homogeneity in Hg(0.89)Mg(0.11)Te. For directionally solidified samples solidified at a rate of 0.09 microns/sec in a thermal gradient of 83 C/cm, a maximum of 0.006 molar percent MnTe radial variation across the Hg0.89)Mn(0.11)Te boules at specific locations was determined using an FTIR technique. This FTIR evaluation of the radial homogeneity also indicated an asymmetrical, convex interface shape during solidification. The asymmetrical, convex shape of the growth interface was confirmed by interrupted directional solidification experiments. These were performed under the same growth conditions as the normally completed directional solidification experiments except that the samples were quenched before the final growth transient was reached. In these experiments, etching and scanning X-ray fluorescence were used to reveal the shape of the solid/liquid interface. Microprobe analysis of composition gradients across the interface was used to confirm the authors' previous work in evaluating the segregation coefficient of Hg(0.89)Mn(0.11)Te alloy. Microprobe analysis of the interface region of the interrupted growth sample revealed a dendritic structure containing secondary and tertiary dendritic arms.

  17. Collaborateurs aux lignes directrices en soins primaires

    PubMed Central

    Allan, G. Michael; Kraut, Roni; Crawshay, Aven; Korownyk, Christina; Vandermeer, Ben; Kolber, Michael R.

    2015-01-01

    Résumé Objectif Déterminer la profession des collaborateurs scientifiques aux lignes directrices, les variables associées aux différences de participation des collaborateurs et si oui ou non les lignes directrices en soins primaires fournissent un énoncé sur les conflits d’intérêts. Type d’étude Analyse rétrospective des lignes directrices en soins primaires affichées sur le site web de l’Association médicale canadienne. Deux extracteurs de données indépendants ont examiné les lignes directrices et ont extrait les données pertinentes. Contexte Canada Principaux paramètres à l’étude Commanditaires des lignes directrices, territoire (national ou provincial) visé par les lignes directrices, profession des collaborateurs scientifiques aux lignes directrices et énoncés de conflits d’intérêts rapportés dans les lignes directrices. Résultats Sur les 296 lignes directrices de pratique clinique trouvées dans la section de la médecine familiale de l’Infobanque AMC, 65 apparaissaient en double et 35 se rapportaient de façon limitée à la médecine familiale. Vingt ne fournissaient aucune information sur les collaborateurs scientifiques, ce qui laissait 176 lignes directrices propices à l’analyse. Au total, il y avait 2495 collaborateurs (auteurs et membres de comité) : 1343 (53,8 %) spécialistes autres que des médecins de famille, 423 (17,0 %) médecins de famille, 141 (5,7 %) infirmières, 75 (3,0 %) pharmaciens, 269 (10,8 %) autres cliniciens, 203 (8,1 %) scientifiques non cliniciens et 41 (1,6 %) collaborateurs de profession inconnue. La proportion des collaborateurs de ces professions différait significativement entre les lignes directrices nationales et provinciales, de même qu’entre les lignes directrices financées par l’industrie et celles qui ne l’étaient pas (p < 0,001 dans les 2 cas). Dans le cas des lignes directrices de pratique clinique provinciales, 30,8 % des collaborateurs étaient des médecins de famille et 37,3 % étaient d’autres spécialistes, comparativement à 13,9 % et à 57,4 %, respectivement, dans le cas des lignes directrices nationales. Parmi les lignes directrices financées par l’industrie, 7,8 % des collaborateurs étaient des médecins de famille et 68,6 % étaient d’autres spécialistes, comparativement à 19,4 % et à 49,9 %, respectivement, parmi les lignes directrices qui n’étaient pas financées par l’industrie. Les conflits d’intérêts n’étaient pas rapportés dans 68,9 % des cas. Lorsqu’ils l’étaient, les énoncés sur les conflits d’intérêts se rapportaient à 48,6 % aux spécialistes autres que les médecins de famille, à 30,0 % aux pharmaciens, à 27,7 % aux médecins de famille et à 10,0 % ou moins aux autres groupes; les différences étaient statistiquement significatives (p < 0,001). Conclusion Les spécialistes autres que les médecins de famille sont plus nombreux que tous les autres fournisseurs de soins de santé et sont plus de 3 fois plus enclins à collaborer aux lignes directrices en soins primaires que ne le sont les médecins de famille. Les énoncés sur les conflits d’intérêts n’apparaissaient que dans une minorité de lignes directrices, et lorsqu’ils apparaissaient, les spécialistes autres que les médecins de famille étaient plus enclins à les rapporter. Les lignes directrices ciblant les médecins de famille devraient compter plus de médecins de famille et de soins primaires et moins de collaborateurs en conflit d’intérêts.

  18. Transition aux normes comptables IAS/IFRS, discipline de march et adquation des fonds

    E-print Network

    Paris-Sud XI, Université de

    Transition aux normes comptables IAS/IFRS, discipline de marché et adéquation des fonds propres aux comptables IAS/IFRS a contraint les banques à assurer une meilleure adéquation des fonds propres aux risques contribuer à étendre aux banques la littérature empirique traitant des effets économiques du passage aux IAS/IFRS

  19. L'Anse Aux Meadows, Newfoundland

    NASA Technical Reports Server (NTRS)

    2008-01-01

    L'Anse aux Meadows is a site on the northernmost tip of the island of Newfoundland, located in the Province of Newfoundland and Labrador, Canada, where the remains of a Viking village were discovered in 1960 by the Norwegians Helge and Anne Ingstad. The only authenticated Viking settlement in North America outside Greenland, it was the site of a multi-year archaeological dig that found dwellings, tools and implements that verified its time frame. The settlement, dating more than five hundred years before Christopher Columbus, contains the earliest European structures in North America. Named a World Heritage site by UNESCO, it is thought by many to be the semi-legendary 'Vinland' settlement of explorer Leif Ericson around AD 1000. The settlement at L'Anse aux Meadows consisted of at least eight buildings, including a forge and smelter, and a lumber yard that supported a shipyard. The largest house measured 28.8 by 15.6 m and consisted of several rooms. Sewing and knitting tools found at the site indicate women were present at L'Anse aux Meadows

    The image was acquired on September 14, 2007, covers an area of 14.2 x 14.6 km, and is located at 51.5 degrees north latitude, 55.6 degrees west longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  20. Performance and techno-economic assessment of several solid-liquid separation technologies for processing dilute-acid pretreated corn stover.

    PubMed

    Sievers, David A; Tao, Ling; Schell, Daniel J

    2014-09-01

    Solid-liquid separation of pretreated lignocellulosic biomass slurries is a critical unit operation employed in several different processes for production of fuels and chemicals. An effective separation process achieves good recovery of solute (sugars) and efficient dewatering of the biomass slurry. Dilute acid pretreated corn stover slurries were subjected to pressure and vacuum filtration and basket centrifugation to evaluate the technical and economic merits of these technologies. Experimental performance results were used to perform detailed process simulations and economic analysis using a 2000 tonne/day biorefinery model to determine differences between the various filtration methods and their process settings. The filtration processes were able to successfully separate pretreated slurries into liquor and solid fractions with estimated sugar recoveries of at least 95% using a cake washing process. A continuous vacuum belt filter produced the most favorable process economics. PMID:24995879

  1. In situ infrared monitoring of the solid/liquid catalyst interface during the three-phase hydrogenation of nitrobenzene over nanosized Au on TiO2.

    PubMed

    Richner, Gilles; van Bokhoven, Jeroen A; Neuhold, Yorck-Michael; Makosch, Martin; Hungerbühler, Konrad

    2011-07-21

    The three-phase hydrogenation of nitrobenzene catalysed by nanosized gold over titania was investigated in a slurry. Simultaneous in situ ATR-FTIR monitoring of the liquid phase and at the solid/liquid catalyst interface identified the species adsorbed on the catalyst and those in the liquid phase during the reaction. Nitrosobenzene was not detected analytically while the spectroscopic measurements strongly indicated phenylhydroxylamine as an intermediate reacting before desorbing from the catalyst surface. Under the same reaction conditions, azobenzene and hydrazobenzene were identified as intermediates during the hydrogenation of azoxybenzene to aniline. When nitrosobenzene or phenylhydroxylamine was alternately fed as reactant, azoxybenzene was produced via a disproportionation route. With the former, azoxybenzene was not further reduced by hydrogen because nitrosobenzene deactivated the catalyst. Combined with H(2) uptake, the spectroscopic measurements provided new insights into the reaction mechanism of the gold catalysed hydrogenation of nitrobenzene and an update of the corresponding kinetics. PMID:21660327

  2. Solid-liquid extraction laser excited time-resolved Shpol'skii spectrometry: a facile method for the direct detection of 15 priority pollutants in water samples.

    PubMed

    Bystol, A J; Whitcomb, J L; Campiglia, A D

    2001-06-15

    A unique method for monitoring polycyclic aromatic hydrocarbons is reported for routine analysis of water samples. The assay consists of a three-step procedure. One hundred milliliters of water is processed through an octadecyl extraction membrane via solid-liquid extraction. The pollutants are eluted with 5 mL of n-hexane and directly determined in the eluting solvent by laser excited time-resolved Shpol'skii spectrometry. Seventy-seven K fluorescence measurements are made with the aid of an optical fiber probe that avoids the complications of classical low-temperature methodology. The total analysis time from the extraction to PAH identification is approximately 5 min per sample. Limits of detection are at the subparts per billion levels. The simplicity of the experimental procedure, the short analysis time, the selectivity, and the excellent analytical figures of merit demonstrate the advantages of this approach for routine analysis of water samples. PMID:11432565

  3. Structure, morphology and cell affinity of poly(L-lactide) films surface-functionalized with chitosan nanofibers via a solid-liquid phase separation technique.

    PubMed

    Zhao, Jianhao; Han, Wanqing; Tang, Minjian; Tu, Mei; Zeng, Rong; Liang, Zhihong; Zhou, Changren

    2013-04-01

    Poly(L-lactide) films with a nano-structured surface by immobilizing chitosan nanofibers (CSNFs) for improving the cell affinity were fabricated via a solid-liquid phase separation technique. The successful grafting of CSNFs on the surface of poly(L-lactide) films was confirmed by the binding energy of N1s at 398.0 eV in the X-ray photoelectron spectroscopy and the amide I and II bands of chitosan at 1650 and 1568 cm(-1) in the Fourier transform infrared spectroscopy. Compared with the poly(L-lactide) film, the hydrophilicity was improved with a lower water contact angle of 83.3±1.9° and 75.3±2.5° for the CSNFs-grafted and CSNFs-grafted/anchored poly(L-lactide) films respectively. The scanning electron microscopy and atomic force microscopy analyses showed that the grafted CSNFs with 50-500 nm in diameter were randomly arranged on the film surface and entangled with the anchored CSNFs on the outermost layer. The 3T3 fibroblasts culture indicated cells tended to attach and stretch along the CSNFs on the film surface. The cell viability measurement revealed that among all the samples, the film with both grafted and anchored CSNFs exhibited the highest cell proliferation rate that was twice as much of the poly(L-lactide) film at 7 d. Herein, engineering a nano-structured surface by solid-liquid phase separation will be a promising tool for surface modification of biomaterials. PMID:23827607

  4. Numerical investigation of solid-liquid two phase flow in a non-clogging centrifugal pump at off-design conditions

    NASA Astrophysics Data System (ADS)

    Zhao, B. J.; Huang, Z. F.; Chen, H. L.; Hou, D. H.

    2012-11-01

    The solid-liquid two-phase flow fields in the non-clogging centrifugal pump with a double-channel impeller have been investigated numerically for the design condition and also off-design conditions, in order to study the solid-liquid two-phase flow pattern and non-clogging mechanism in non-clogging centrifugal pumps. The main conclusions include: The sand volume fraction distribution is extremely inhomogeneous in the whole flow channel of the pump at off-design conditions. In the impeller, particles mainly flow along the pressure surface and hub; In the volute, particles mainly accumulate in the region near to the exit of volute, the largest sand volume fraction is observed at the tongue, and a large number of particles collide with volute wall and exit the volute after circling around the volute for several times. When the particle diameter increases, particles tend to accumulate on the pressure side of the impeller, and more particles crash with the pressure side of the blade. And larger sand volume fraction gratitude is also observed in the whole flow channel of the pump. With the decrease of the inlet sand volume fraction, particles tend to accumulate on the suction side of the blade. Compared with the particle diameter, the inlet sand volume fraction has less influence on the sand volume fraction gratitude in the whole channel of the pump. At the large flow rate, the minimum and maximum sand volume fraction in the whole flow channel of the model pump tends to be smaller than that at the small flow rate. Thus, it is concluded that the water transportation capacity increases with the flow rate. This research will strengthen people's understanding of the multiphase flow pattern in non-clogging centrifugal pumps, thus provides a theoretical basis for the optimal design of non-clogging centrifugal pumps.

  5. DIVULGATION FINANCIERE ET TRANSITION AUX IAS-IFRS

    E-print Network

    Paris-Sud XI, Université de

    1 DIVULGATION FINANCIERE ET TRANSITION AUX IAS-IFRS CONTENU ET DETERMINANTS La mise en place progressive du nouveau référentiel comptable communément appelé IAS-IFRS a imposé aux sociétés concernées un. The progressive installation of the new acounting framework commonly called IAS-IFRS requires from the companies

  6. DIVULGATION FINANCIERE ET TRANSITION AUX IAS-IFRS

    E-print Network

    Boyer, Edmond

    DIVULGATION FINANCIERE ET TRANSITION AUX IAS-IFRS LE ROLE DU COMITE D'AUDIT ET DES AUDITEURS Le passage au nouveau référentiel IFRS a imposé aux sociétés concernées un important effort de communication of the new accounting framework commonly called IAS-IFRS requires from the companies concerned

  7. Des pionniers autoconstructeurs aux cooprateurs : histoire des Castors en Aquitaine

    E-print Network

    Boyer, Edmond

    Des pionniers autoconstructeurs aux coopérateurs : histoire des Castors en Aquitaine Julie ­ Histoire des Castors en Aquitaine - 2010 2 Préambule Ce travail est un manuscrit en cours de travail. Il Castors en Aquitaine, des pionniers autoconstructeurs aux coopérateurs (1948-1970) initialement traité

  8. MASTER RECHERCHE EN Littrature franaise : de la Renaissance aux Lumires

    E-print Network

    Gutkin, Boris

    1 MASTER RECHERCHE EN Littérature française : de la Renaissance aux Lumières ENSPARIS 3PARIS 4 Master de littérature française ­ De la Renaissance aux Lumières Département Littérature et Langages : Date et signature : #12;2 MASTER RECHERCHE EN Littérature française : de la Renaissance

  9. Bioproduction of the aroma compound 2-phenylethanol in a solid-liquid two-phase partitioning bioreactor system by Kluyveromyces marxianus.

    PubMed

    Gao, Fang; Daugulis, Andrew J

    2009-10-01

    The rose-like aroma compound 2-phenylethanol (2-PE) is an important fragrance and flavor ingredient. Several yeast strains are able to convert l-phenylalanine (l-phe) to 2-PE among which Kluyveromyces marxianus has shown promising results. The limitation of this process is the low product concentration and productivity primarily due to end product inhibition. This study explored the possibility and benefits of using a solid-liquid Two-Phase Partition Bioreactor (TPPB) system as an in situ product removal technique. The system applies polymer beads as the sequestering immiscible phase to partition 2-PE and reduce the aqueous 2-PE concentration to non-inhibitory levels. Among six polymers screened for extracting 2-PE, Hytrel 8206 performed best with a partition coefficient of 79. The desired product stored in the polymer was ultimately extracted using methanol. A 3 L working volume solid-liquid batch mode TPPB using 500 g Hytrel as the sequestering phase generated a final overall 2-PE concentration of 13.7 g/L, the highest reported in the current literature. This was based on a polymer phase concentration of 88.74 g/L and aqueous phase concentration of 1.2 g/L. Even better results were achieved via contact with more polymers (approximately 900 g) with the aqueous phase applying a semi-continuous reactor configuration. In this system, a final 2-PE concentration (overall) of 20.4 g/L was achieved with 1.4 g/L in the aqueous and 97 g/L in the polymer phase. The overall productivities of these two reactor systems were 0.38 and 0.43 g/L h, respectively. This is the first report in the literature of the use of a polymer sequestering phase to enhance the bioproduction of 2-PE, and exceeds the performance of two-liquid phase systems in terms of productivity as well as ease of operation (no emulsions) and ultimate product recovery. PMID:19517523

  10. Understanding the relationship between biotherapeutic protein stability and solid-liquid interfacial shear in constant region mutants of IgG1 and IgG4.

    PubMed

    Tavakoli-Keshe, Roumteen; Phillips, Jonathan J; Turner, Richard; Bracewell, Daniel G

    2014-02-01

    Relative stability of therapeutic antibody candidates is currently evaluated primarily through their response to thermal degradation, yet this technique is not always predictive of stability in manufacture, shipping, and storage. A rotating disk shear device is proposed that produces defined shear conditions at a known solid-liquid interface to measure stability in this environment. Five variants of IgG1 and IgG4 antibodies were created using combinations of two discrete triple amino acid sequence mutations denoted TM and YTE. Antibodies were ranked for stability based on shear device output (protein decay coefficient, PDC), and compared with accelerated thermal stability data and the melting temperature of the CH2 domain (Tm 1) from differential scanning calorimetry to investigate technique complimentarity. Results suggest that the techniques are orthogonal, with thermal methods based on intramolecular interaction and shear device stability based on localized unfolding revealing less stable regions that drive aggregation. Molecular modeling shows the modifications' effects on the antibody structures and indicates a possible role for Fc conformation and Fab-Fc docking in determining suspended protein stability. The data introduce the PDC value as an orthogonal stability indicator, complementary to traditional thermal methods, allowing lead antibody selection based on a more full understanding of process stability. PMID:24357426

  11. High quality, giant crystalline-Ge stripes on insulating substrate by rapid-thermal-annealing of Sn-doped amorphous-Ge in solid-liquid coexisting region

    NASA Astrophysics Data System (ADS)

    Matsumura, Ryo; Kai, Yuki; Chikita, Hironori; Sadoh, Taizoh; Miyao, Masanobu

    2015-06-01

    Formation of large-grain (?30 ?m) Ge crystals on insulating substrates is strongly desired to achieve high-speed thin-film transistors. For this purpose, we propose the methods of Sn-doping into amorphous-Ge combined with rapid-thermal-annealing (RTA) in the solid-liquid coexisting temperature region for the Ge-Sn alloy system. The densities of micro-crystal-nuclei formed in this temperature region become low by tuning the RTA temperature close to the liquidus curve, which enhances the lateral growth of GeSn. Thanks to the very small segregation coefficient of Sn, almost all Sn atoms segregate toward edges of the stripes during growth. Agglomeration of GeSn degrades the surface morphologies; however, it is significantly improved by lowering the initial Sn concentration. As a result, pure Ge with large crystal grains (˜40 ?m) with smooth surface are obtained by optimizing the initial Sn concentration as low as 3 ˜ 5%. Lateral growth lengths are further increased through decreasing the number of nuclei in stripes by narrowing stripe width. In this way, high-crystallinity giant Ge crystals (˜200 ?m) are obtained for the stripe width of 3 ?m. This "Si-seed free" technique for formation of large-grain pure Ge crystals is very useful to realize high-performance thin-film devices on insulator.

  12. Solid-liquid-solid extraction of heavy metals (Cr, Cu, Cd, Ni and Pb) in aqueous systems of zeolite-sewage sludge.

    PubMed

    Sprynskyy, Myroslav

    2009-01-30

    This paper presents results of kinetic and equilibrium studies of the removal of heavy metals (Cr, Cu, Cd, Ni and Pb) from the sewage sludge using a new technique of solid-liquid-solid extraction with the adsorption-diffusion column filled by the zeolite. The metal extraction onto the zeolite from aqueous solution of the clinoptilolite and the sludge composition is characterized by three stages: intensive extraction, inversion and stabilization with the moderate extraction increase. Addition of 25% of the zeolite provides extraction efficiency of cadmium and lead of about 84%, chromium, copper and nickel of 66%, 61% and 50%, respectively. The estimated values of Gibbs free energy change DeltaG show that the metals extraction by the clinoptilolite may be considered as a physical adsorption. The negative values of DeltaG testify to an exothermic nature of the process. The difference between energetic potentials of the components is a driving force of the metal redistribution in the system "clinoptilolite-water-sludge". PMID:18538472

  13. Nanopatterning of Surfaces with Monometallic and Heterobimetallic 1D Coordination Polymers: A Molecular Tectonics Approach at the Solid/Liquid Interface.

    PubMed

    El Garah, Mohamed; Marets, Nicolas; Mauro, Matteo; Aliprandi, Alessandro; Bonacchi, Sara; De Cola, Luisa; Ciesielski, Artur; Bulach, Véronique; Hosseini, Mir Wais; Samorì, Paolo

    2015-07-01

    The self-assembly of multiple molecular components into complex supramolecular architectures is ubiquitous in nature and constitutes one of the most powerful strategies to fabricate multifunctional nanomaterials making use of the bottom-up approach. When spatial confinement in two dimensions on a solid substrate is employed, this approach can be exploited to generate periodically ordered structures from suitably designed molecular tectons. In this study we demonstrate that physisorbed directional periodic arrays of monometallic or heterobimetallic coordination polymers can be generated on a highly oriented pyrolitic graphite surface by combinations of a suitably designed directional organic tecton or metallatecton based on a porphyrin or nickel(II) metalloporphyrin backbone bearing both a pyridyl unit and a terpyridyl unit acting as coordinating sites for CoCl2. The periodic architectures were visualized at the solid/liquid interface with a submolecular resolution by scanning tunneling microscopy and corroborated by combined density functional and time-dependent density functional theory calculations. The capacity to nanopattern the surface for the first time with two distinct metallic centers exhibiting different electronic and optical properties is a key step toward the bottom-up construction of robust multicomponent and, thus, multifunctional molecular nanostructures and nanodevices. PMID:26076095

  14. Numerical research on the effects of impeller pump-out vanes on axial force in a solid-liquid screw centrifugal pump

    NASA Astrophysics Data System (ADS)

    Cheng, X. R.; Li, R. N.; Gao, Y.; Guo, W. L.

    2013-12-01

    A commercial CFD code has been used to predict the performance of a screw centrifugal pump with pump-out vanes, especially when changing regularity of impeller axial force based on the solid-liquid two-phase flow. The Unsteady Reynolds Averaged Navier-Stokes (URANS) approach has been applied to solve the unsteady, incompressible, three-dimensional turbulent. The SIMPLEC algorithm, standard wall functions and mix two-phase flow model were applied. The RNG k ?-model was used to account the turbulence effects. By changing the number of impeller pump-out vanes and width, six different screw centrifugal pump numerical simulation projects were given, and each scheme in the different solid volume fraction were calculated respectively. The change rules of axial force, velocity and pressure distribution of flow field were obtained on the different condition and different volume fraction. The results showed that the axial forces values based solid-fluid two-phase greater than based single-phase clear water, but both changing regularity of the axial force were consistent; as same condition, the same solid-phase volume concentration, with the increase of pump-out vanes number or width, the impeller axial force increased as well. Meanwhile the number of the pump-out vanes and the width of pump-out vanes in balancing the impeller axial force, there are the most optimal value.

  15. High pressure in situ x-ray absorption spectroscopy cell for studying simultaneously the liquid phase and the solid/liquid interface

    NASA Astrophysics Data System (ADS)

    Grunwaldt, Jan-Dierk; Ramin, Michael; Rohr, Markus; Michailovski, Alexej; Patzke, Greta R.; Baiker, Alfons

    2005-05-01

    A high pressure in situ x-ray absorption spectroscopy cell with two different path lengths and path positions is presented for studying element-specifically both the liquid phase and the solid/liquid interface at pressures up to 250 bar and temperatures up to 220 °C. For this purpose, one x-ray path probes the bottom, while the other x-ray path penetrates through the middle of the in situ cell. The basic design of the cell resembles a 10 ml volume batch reactor, which is equipped with in- and outlet lines to dose compressed gases and liquids as well as a stirrer for good mixing. Due to the use of a polyetheretherketone inset it is also suitable for measurements under corrosive conditions. The characteristic features of the cell are illustrated using case studies from catalysis and solid state chemistry: (a) the ruthenium-catalyzed formylation of an amine in "supercritical" carbon dioxide in the presence of hydrogen; (b) the cycloaddition of carbon dioxide to propylene oxide in the presence of a solid Zn-based catalyst, and (c) the solvothermal synthesis of MoO3 nanorods from MoO3•2H2O.

  16. Low energy electron diffraction (LEED) and sum frequency generation (SFG) vibrational spectroscopy studies of solid-vacuum, solid-air and solid-liquid interfaces

    SciTech Connect

    Hoffer, Saskia

    2002-08-19

    Electron based surface probing techniques can provide detailed information about surface structure or chemical composition in vacuum environments. The development of new surface techniques has made possible in situ molecular level studies of solid-gas interfaces and more recently, solid-liquid interfaces. The aim of this dissertation is two-fold. First, by using novel sample preparation, Low Energy Electron Diffraction (LEED) and other traditional ultra high vacuum (UHV) techniques are shown to provide new information on the insulator/vacuum interface. The surface structure of the classic insulator NaCl has been determined using these methods. Second, using sum frequency generation (SFG) surface specific vibrational spectroscopy studies were performed on both the biopolymer/air and electrode/electrolyte interfaces. The surface structure and composition of polyetherurethane-silicone copolymers were determined in air using SFG, atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). SFG studies of the electrode (platinum, gold and copper)/electrolyte interface were performed as a function of applied potential in an electrochemical cell.

  17. Understanding the Relationship Between Biotherapeutic Protein Stability and Solid–Liquid Interfacial Shear in Constant Region Mutants of IgG1 and IgG4

    PubMed Central

    Tavakoli-Keshe, Roumteen; Phillips, Jonathan J; Turner, Richard; Bracewell, Daniel G

    2014-01-01

    Relative stability of therapeutic antibody candidates is currently evaluated primarily through their response to thermal degradation, yet this technique is not always predictive of stability in manufacture, shipping, and storage. A rotating disk shear device is proposed that produces defined shear conditions at a known solid–liquid interface to measure stability in this environment. Five variants of IgG1 and IgG4 antibodies were created using combinations of two discrete triple amino acid sequence mutations denoted TM and YTE. Antibodies were ranked for stability based on shear device output (protein decay coefficient, PDC), and compared with accelerated thermal stability data and the melting temperature of the CH2 domain (Tm1) from differential scanning calorimetry to investigate technique complimentarity. Results suggest that the techniques are orthogonal, with thermal methods based on intramolecular interaction and shear device stability based on localized unfolding revealing less stable regions that drive aggregation. Molecular modeling shows the modifications’ effects on the antibody structures and indicates a possible role for Fc conformation and Fab-Fc docking in determining suspended protein stability. The data introduce the PDC value as an orthogonal stability indicator, complementary to traditional thermal methods, allowing lead antibody selection based on a more full understanding of process stability. © 2013 The Authors. Journal of Pharmaceutical Sciences published by Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:437–444, 2014 PMID:24357426

  18. Guy Michelat Croyances aux parasciences : dimensions sociales et culturelles

    E-print Network

    Boyer, Edmond

    -2969_1986_num_27_2_2302 #12;Résumé L'essor des parasciences au sein de nos sociétés semble constituer un fait MICHELAT Croyances aux parasciences : dimensions sociales et culturelles* Résumé L'essor des parasciences

  19. Étude des équilibres solide-liquide du système quaternaire réciproque H 2O?UO 2(NO 3) 2, H 2 O 2 ( HNO 3) 2 , UO 4. Partie 1. Méthodes et techniques d'étude

    Microsoft Academic Search

    J. J Counioux; S Gentil; R Tenu

    1995-01-01

    Hydrated uranium peroxide (UO4 · nH2O with n = 2, 4 or 92) can be obtained by the reaction between hydrogen peroxide and uranyl nitrate. The optimal conditions for obtaining these compounds in a nitric medium require knowledge of the solid-liquid equilibrium of the reciprocal quaternary system H2O?UO2(NO3)2, H2O2(HNO3)2, UO4. The spontaneous decomposition of hydrogen peroxide into water and oxygen

  20. Solid-liquid extraction studies of Zn(II), Cu(II) and Cd(II) from chloride media with impregnated resins containing mixtures of organophosphorus compounds immobilized on to Amberlite XAD2

    Microsoft Academic Search

    J. L. Cortina; N. Miralles; A. M. Sastre; M. Aguilar

    1995-01-01

    The solid-liquid extraction of Zn(II), Cu(II) and Cd(II) from chloride medium at 0.1 and 0.5 M inonic strength and 25°C by impregnated resins containing mixtures of di(2-ethylhexyl)phosphoric acid (DEHPA = HL) and tri-n-octylphosphine oxide (TOPO = S) was studied. Impregnated resins containing TOPO and mixtures of DEHPA and TOPO, by direct adsorption of both extractants into a styrene\\/divinylbenzene macroporous support,

  1. BEHAVIOR OF SURFACTANT MIXTURE AT SOLID/LIQUID AND OIL/LIQUID INTERFACE IN CHEMICAL FLOODING SYSTEMS

    SciTech Connect

    Prof. P. Somasundaran

    2002-03-01

    The aim of the project is to develop and evaluate efficient novel surfactant mixtures for enhanced oil recovery. Preliminary ultra-filtration tests suggest that two kinds of micelles may exist in binary surfactant mixtures at different concentrations. Due to the important role played in interfacial processes by micelles as determined by their structures, focus of the current work is on the delineation of the relationship between such aggregate structures and chemical compositions of the surfactants. A novel analytical centrifuge application is explored to generate information on structures of different surfactants aggregates. In this report, optical systems, typical output of the analytical ultracentrifuge results and four basic experiments are discussed. Initial sedimentation velocity investigations were conducted using nonyl phenol ethoxylated decyl ether (NP-10) to choose the best analytical protocol, calculate the partial specific volume and obtain information on sedimentation coefficient, aggregation mass of micelles. The partial specific volume was calculated to be 0.920. Four softwares: Optima{trademark} XL-A/XL-I data analysis software, DCDT+, Svedberg and SEDFIT, were compared for the analysis of sedimentation velocity experimental data. The sedimentation coefficient and aggregation number of NP-10 micelles obtained using the first three softwares at 25 C are 209, 127, and 111, respectively. The last one is closest to the result from Light Scattering. The reason for the differences in numbers obtained using the three softwares is discussed. Based on these tests, Svedberg and SEDFIT analysis are chosen for further studies. This approach using the analytical ultracentrifugation offers an unprecedented opportunity now to obtain important information on mixed micelles and their role in interfacial processes.

  2. BEHAVIOR OF SURFACTANT MIXTURES AT SOLID/LIQUID AND OIL/LIQUID INTERFACES IN CHEMICAL FLOODING SYSTEMS

    SciTech Connect

    Prof. P. Somasundaran

    2002-09-30

    The aim of the project is to develop and evaluate efficient novel surfactant mixtures for enhanced oil recovery. Surfactant loss by adsorption or precipitation depends to a great extent on the type of surfactant complexes and aggregates formed. Such information as well as techniques to generate the information is lacking currently particularly for surfactant mixtures and surfactant/polymer systems. A novel analytical centrifuge application is explored during the last period to generate information on structures-performance relationship for different surfactant aggregates in solution and, in turn, at interfaces. To use analytical untracentrifuge for surfactant mixtures, information on partial specific volumes of single surfactants and their mixtures is required. Towards this purpose, surface tension and density measurements were performed to determine critical micellar concentrations (cmc), partial specific volumes of n-dodecyl-{beta}-Dmaltoside (DM), nonyl phenol ethoxylated decyl ether (NP-10) and their 1:1 mixtures at 25 C. Durchschlag's theoretical calculation method was adopted to calculate the partial specific volumes. Effects of temperature and mixing, as well as methods used for estimation on micellization and partial specific volumes were studied during the current period. Surface tension results revealed no interaction between the two surfactants in mixed micelles. Partial specific volume measurements also indicated no interaction in mixed micelles. Maximum adsorption density, area per molecule and free energy of micellization were also calculated. Partial specific volumes were estimated by two experimental methods: d{sub {rho}}/dc and V{sub {sigma}}. The difference between the results of using the two methods is within 0.5% deviation. It was found that the partial specific volume is concentration dependent and sensitive to changes in temperature. The information generated in this study will be used for the study of surfactant aggregate mass distribution in mixed systems. Such information will in future be used to identify optimum surfactant.

  3. Soins Aux Brules Apres Un Accident Nucleaire

    PubMed Central

    Bargues, L.; Donat, N.; Jault, P.; Leclerc, T.

    2010-01-01

    Summary Les lésions radiques sont dues le plus souvent à des radio-isotopes utilisés dans l’industrie. L’explosion d’un réacteur nucléaire, les armes nucléaires ou une attaque terroriste constituent un risque d’afflux massif de victimes brûlées. Les radiations ionisantes occasionnent des brûlures thermiques, des syndromes d’irradiation aiguë avec pancytopénie et des signes cutanés retardés. Après une période de latence, des symptômes cutanés apparaissent et leur profondeur est proportionnelle à la dose reçue. Les protocoles habituels de réanimation des brûlés s’appliquent ici. Les soins aux irradiés nécessitent aussi une mesure de l’irradiation et une décontamination par des personnels entraînés. En cas de catastrophe nucléaire, la priorité est d’optimiser les structures existantes et de préserver les moyens pour les patients ayant la plus forte probabilité de survie. Après un accident nucléaire isolé, les difficultés dans les centres de brûlés sont l’évaluation de la profondeur et les techniques chirurgicales de couverture cutanée. La préparation des moyens médicaux et des centres de brûlés est nécessaire pour faire face à la prise en charge de ces brûlures différentes et complexes. PMID:21991218

  4. Simultaneous multi-mycotoxin determination in nutmeg by ultrasound-assisted solid-liquid extraction and immunoaffinity column clean-up coupled with liquid chromatography and on-line post-column photochemical derivatization-fluorescence detection.

    PubMed

    Kong, Wei-Jun; Liu, Shu-Yu; Qiu, Feng; Xiao, Xiao-He; Yang, Mei-Hua

    2013-05-01

    A simple and sensitive analytical method based on ultrasound-assisted solid-liquid extraction and immunoaffinity column clean-up coupled with high performance liquid chromatography and on-line post-column photochemical derivatization-fluorescence detection (USLE-IAC-HPLC-PCD-FLD) has been developed for simultaneous multi-mycotoxin determination of aflatoxins B1, B2, G1, G2 (AFB1, AFB2, AFG1, AFG2) and ochratoxin A (OTA) in 13 edible and medicinal nutmeg samples marketed in China. AFs and OTA were extracted from nutmeg samples by ultrasonication using a methanol?:?water (80?:?20, v/v) solution, followed by an IAC clean-up step. Different USL extraction conditions, pre-processing ways for nutmeg sample and clean-up columns for mycotoxins, as well as HPLC-PCD-FLD parameters (mobile phase, column temperature, elution procedure, excitation and emission wavelengths) were optimized. This method, which was appraised for analyzing nutmeg samples, showed satisfactory results with reference to limits of detection (LODs) (from 0.02 to 0.25 ?g kg(-1)), limits of quantification (LOQs) (from 0.06 to 0.8 ?g kg(-1)), linear ranges (up to 30 ng mL(-1) for AFB1, AFG1 and OTA and 9 ng mL(-1) for AFB2 and AFG2), intra- and inter-day variability (all <2%) and average recoveries (from 79.6 to 90.8% for AFs and from 93.6 to 97.3% for OTA, respectively). The results of the application of developed method in nutmeg samples have elucidated that four samples were detected with contamination of AFs and one with OTA. AFB1 was the most frequently found mycotoxin in 30.8% of nutmeg samples at contamination levels of 0.73-16.31 ?g kg(-1). At least two different mycotoxins were co-occurred in three samples, and three AFs were simultaneously detected in one sample. PMID:23486692

  5. Fundamentals and Applications of Laser-Induced Breakdown Spectroscopy

    Microsoft Academic Search

    D. A. Rusak; B. C. Castle; B. W. Smith; J. D. Winefordner

    1997-01-01

    Laser-induced breakdown spectroscopy is reviewed by dividing the literature into three categories according to target phase: solid, liquid, or gas. Within each category, the literature is further divided into a fundamental studies section and an analytical results and applications section.

  6. Enhanced biotransformation of 2-phenylethanol with ethanol oxidation in a solid-liquid two-phase system by active dry yeast.

    PubMed

    Rong, Shaofeng; Ding, Baomei; Zhang, Xiaoli; Zheng, Xuesong; Wang, Yifei

    2011-11-01

    2-Phenylethanol (2-PE) can be produced from L: -phenylalanine (L: -Phe) with the oxidation degradation of ethanol by active dry yeast. In this study, the catalysis effect of ethanol on biotransforming L: -Phe into 2-PE by yeast was evaluated and optimized. The results indicated that increasing ethanol concentration was beneficial for enhancing 2-PE concentration but lowered the 2-PE productivity. Initial ethanol concentration above 25 g/l could strongly inhibit the 2-PE production. To obtain 2-PE with desirable concentrations with an economical operation mode, three fed-batch biotransformation operation methods using ethanol or/and glucose were carried out in a solid-liquid two-phase system. When using ethanol alone with the initial concentration of 10 g/l, the total concentration and overall productivity of 2-PE were 7.6 g/l and 0.065 g l(-1) h(-1), respectively. Furthermore, an experiment with controlled glucose solely (higher than 2 g/l) was finished. In this case, phenylacetaldehyde (PA) was detected along with ethanol accumulation, suggesting that reaction of PA ? 2-PE in Ehrlich pathway was inhibited. To further enhance 2-PE production by using glucose only, a novel operation strategy to simultaneously control rates of glucose glycolysis and ethanol oxidative degradation with the aid of ISPR techniques was developed. With this strategy, 2-PE concentration and yield based on glucose consumption reached a higher level of 14.8 g/l and 0.12 g-PE/g-glucose, respectively, and these are the highest values reported up to date with the fed-batch biotransformation operation mode. PMID:21910022

  7. Determination of caffeoylquinic acids in feed and related products by focused ultrasound solid-liquid extraction and ultra-high performance liquid chromatography-mass spectrometry.

    PubMed

    Tena, M T; Martínez-Moral, M P; Cardozo, P W

    2015-06-26

    A method to determine caffeoylquinic acids (CQAs) in three sources (herbal extract, feed additive and finished feed) using for the first time focused ultrasound solid-liquid extraction (FUSLE) followed by ultra-high performance liquid chromatography (UPLC) coupled to quadrupole-time of flight mass spectrometry is presented. Pressurized liquid extraction (PLE) was also tested as extraction technique but it was discarded because cynarin was not stable under temperature values used in PLE. The separation of the CQAs isomers was carried out in only seven minutes. FUSLE variables such as extraction solvent, power and time were optimized by a central composite design. Under optimal conditions, FUSLE extraction was performed with 8mL of an 83:17 methanol-water mixture for 30s at a power of 60%. Only two extraction steps were found necessary to recover analytes quantitatively. Sensitivity, linearity, accuracy and precision were established. Matrix effect was studied for each type of sample. It was not detected for mono-CQAs, whereas the cynarin signal was strongly decreased due to ionization suppression in presence of matrix components; so the quantification by standard addition was mandatory for the determination of di-caffeoylquinic acids. Finally, the method was applied to the analysis of herbal extracts, feed additives and finished feed. In all samples, chlorogenic acid was the predominant CQA, followed by criptochlorogenic acid, neochlorogenic acid and cynarin. The method allows an efficient determination of chlorogenic acid with good recovery rates. Therefore, it may be used for screening of raw material and for process and quality control in feed manufacture. PMID:25981290

  8. The coupling of surface charge and boundary slip at the solid-liquid interface and their combined effect on fluid drag: A review.

    PubMed

    Jing, Dalei; Bhushan, Bharat

    2015-09-15

    Fluid drag of micro/nano fluidic systems has inspired wide scientific interest. Surface charge and boundary slip at the solid-liquid interface are believed to affect fluid drag. This review summarizes the recent studies on the coupling of surface charge and slip, and their combined effect on fluid drag at micro/nano scale. The effect of pH on surface charge of borosilicate glass and silica surfaces in deionized (DI) water and saline solution is discussed using a method based on colloidal probe atomic force microscopy (AFM). The boundary slip of various oil-solid interfaces are discussed for samples with different degrees of oleophobicity prepared by nanoparticle-binder system. By changing the pH of solution or applying an electric field, effect of surface charge on slip of a smooth hydrophobic octadecyltrichlorosilane (OTS) in DI water and saline solution is studied. A theoretical model incorporating the coupling relationship between surface charge and slip is used to discuss the combined effect of surface charge-induced electric double layer (EDL) and slip on fluid drag of pressure-driven flow in a one-dimensional parallel-plates microchannel. A theoretical method is used to reduce the fluid drag. The studies show that the increasing magnitude of surface charge density leads to a decrease in slip length. The surface charge results in a larger fluid drag, and the coupling of surface charge and slip can further increase the fluid drag. Surface charge-induced EDLs with asymmetric zeta potentials can effectively reduce the fluid drag. PMID:26021432

  9. ASSIMILATION DES EXPRIENCES DE HALL ET FARADAY AUX EFFETS DU GYROSCOPE;

    E-print Network

    Paris-Sud XI, Université de

    269 ASSIMILATION DES EXPÉRIENCES DE HALL ET FARADAY AUX EFFETS DU GYROSCOPE; PAR 31. B. ÉLIE. L élémentaires suivant O.x, c'est-à-dire perpendiculaires aux deux premières. Or le gyroscope présente le fait

  10. Solid-liquid extraction and cation-exchange solid-phase extraction using a mixed-mode polymeric sorbent of Datura and related alkaloids.

    PubMed

    Mroczek, Tomasz; G?owniak, Kazimierz; Kowalska, Joanna

    2006-02-24

    Tropane alkaloids solid-liquid extraction methods were developed and comprised ambient pressure ones: extraction with hot solvent, extraction at room temperature, on ultrasonic bath as well as pressurised liquid extraction (PLE) techniques. The highest yields of l-hyoscyamine in methanol PLE method (3 x 5 min, 110 degrees C) and scopolamine extracted with 1% tartaric acid in methanol (15 min, 90 degrees C) were determined. A mixed-mode reversed-phase cation-exchange solid-phase extraction (SPE) procedure was optimised for simultaneous recoveries of L-hyoscyamine, scopolamine, scopolamine-N-oxide from plant extracts as well as quaternary alkaloid representative: scopolamine-N-methyl bromide. First three alkaloids were efficiently eluted (recoveries 80-100%) from an Oasis MCX cartridge with methanol-10% ammonia (3:1, v/v) solution, whereas for the quaternary salt tetrahydrofuran-methanol-25% ammonia (6:1:3, v/v) was used with recoveries 52-6%. HPTLC-densitometric assay on silica gel plates was elaborated at 205 nm without derivatization and included: single development (over a distance 9.5 cm) with acetone-methanol-water-25% ammonia (85:5:5:8, v/v) mobile phase for L-hyoscyamine and scopolamine separation, whereas for scopolamine-N-oxide and scopolamine-N-methyl bromide a second development (to a distance 5.5 cm) with acetonitrile-methanol-85% formic acid (120:5:5, v/v) was applied. Newly elaborated RP-HPLC-diode array detection method was performed on Waters XTerra RP-18 column with gradient of acetonitrile in 15 mM ammonia solution and alkaloids were baseline separated within 20 min. Both chromatographic methods were validated and their quantitative results were compared. Good correlation between HPLC and HPTLC quantitative results was measured (correlation coefficients of mean values were 0.92086 and 0.99995 for L-hyoscyamine and scopolamine, respectively). In the RP-HPLC method, which was from 1.5- up to 7-fold more sensitive than HPTLC, limits of detection (LOD) and limits of quantitation (LOQ, in bracket) were (in ng/microl) as follows: 0.25 (0.82) for L-hyoscyamine, 0.29 (0.97) for scopolamine, 0.13 (0.45) for scopolamine-N-oxide and 0.58 (1.91) for scopolamine-N-methyl bromide. By the use of the optimised chromatographic methods, 14 various samples from the leaves and fruits of Datura sp. were screened for L-hyoscyamine and scopolamine contents and the most promising samples were established. PMID:16388811

  11. Document1 Bordigoni 04/07/05 1 Sara aux Saintes-Maries-de-la-Mer,

    E-print Network

    Boyer, Edmond

    Document1 Bordigoni 04/07/05 1 Sara aux Saintes-Maries-de-la-Mer, métaphore de la présence gitane dans le " monde des Gadjé " Le pèlerinage des Gitans aux Saintes-Maries-de-la-Mer est devenu, au XXe'affirmation de leur foi chrétienne. En 1955, la revue Études tsiganes consacre son numéro 4 aux Saintes-Maries-de-la-Mer

  12. Phenomena associated with melting and supercooling in aluminum and the solid-liquid interface in an aluminum-silicon base alloy investigated by in-situ analytical transmission electron microscopy

    NASA Astrophysics Data System (ADS)

    Palanisamy, Prakash

    Crystal growth is an important technique for controlling the microstructure of materials, and hence, studies pertaining to crystal growth are crucial for developing new materials with novel properties. The present research explores the behavior of the core and valence electrons, and the nearest-neighbor atomic distance during heating and cooling of pure Al through the melting temperature, as well as the properties associated with the solid-liquid interface in a commercially important Al-Si-Cu-Mg alloy, using in-situ analytical transmission electron microscopy (TEM). Electron energy-loss spectroscopy (EELS) in a TEM was used to follow changes in the valence electron density through the melting temperature and during supercooling in pure Al particles. A non-linear plasmon energy change observed during heating solid Al is due to a phonon anharmonicity that is not present in liquid Al during heating. Similarly, a non-linear plasmon behavior observed during supercooling liquid Al could due to local ordering in the liquid. Comparing the full-width at half-maximum of the plasmon peaks show that damping of plasmons is faster in liquid than in solid Al due to electron-phonon interactions and/or Anderson localization. The extended energy-loss fine structure (EXEFLS) in the EELS spectrum is sensitive to the nearest-neighbor atomic distance and coordination in a material. A comparison of the nearest-neighbor distance and the inverse volume plasmon energy change through the melting temperature shows good agreement in the solid Al, whereas the correlation is less good in liquid Al because thermal vibrations (Debye-Waller factor) dampen the EXELFS oscillation at high temperatures. A qualitative comparison of the energy-loss near edge spectra (ELNES) of solid and liquid Al in both superheated and supercooled states shows that their partial electron density of states are quantitatively different and that the presence or absence of crystallinity is the most important factor contributing to the ELNES. The partitioning of solute elements was investigated by measuring the Cu concentrations in solid Si, liquid Al and at the solid-liquid interface at 585 °C, where the particle is partially molten, and subsequently undercooling to 565 and 470 °C. The Cu concentration after fluorescence correction was compared with thermodynamic calculations. The results shows that Cu segregation during undercooling assists in nucleating Al2Cu prior to Mg 2Si phase at a high-index Si facet-liquid Al interface under non-equilibrium conditions. The heterogeneous segregation of Cu at the interface was determined to be a thermodynamically driven process by measuring the Cu concentration in liquid Al and at the solid-liquid interface for prolonged times at temperature. The plasmon at a solid-liquid interface in an Al-Si alloy particle was investigated by stepping a 0.6 nm diameter electron beam at 0.8 nm increments across a singular Si{111}-liquid Al interface in sub-eV, sub-A microscope (SESAM). Low energy-loss spectra acquired across solid-liquid interface were compared with calculations using dielectric theory. The result shows that a unique plasmon resonance is present at the interface between the crystalline Si and liquid Al, thereby giving rise to a plasmon peak at 15.5 eV between the Si (16.3 eV) and liquid Al (14.2 eV) plasmons in the experimental EEL spectra. This result was corroborated with energy-filtered TEM. The intensity profile across the solid-liquid interface in the energy-filtered image shows that the interface plasmon signal is delocalized to within ˜5.5 nm of the interface.

  13. Simultaneous C- and N-Alkylation of 2Oxo4,6-diaryl-1,2,3,4-tetrahydropyridine-3-carbonitrile Under Solid–Liquid Phase-Transfer Conditions

    Microsoft Academic Search

    Hetal C. Shah; Vaishali H. Shah; Nirmal D. Desai

    2010-01-01

    The alkylation of 2-oxo-4,6-diaryl-1,2,3,4-tetrahydropyridine-3-carbonitrile 1 has been carried out using different alkyl\\/arylating agents in solid–liquid phase-transfer catalysis conditions. The aim was to study the effect of steric hindrance offered by the aryl group in the sixth position of the pyridine ring on the ambient N- vs. O-alkylation ratio. Simultaneous C- and N-alkylation was encountered and confirmed by x-ray crystallography. Our

  14. POLYMORPHISME DU COMPOS DFINI Mn Bi AUX TEMPRATURES

    E-print Network

    Paris-Sud XI, Université de

    143 POLYMORPHISME DU COMPOSÉ DÉFINI Mn Bi AUX TEMPÉRATURES DE DISPARITION ET DE RÉAPPARITION DE L correspond à la disparition de l'aimantation spontanée de l'alliage MnBi, une variation brusque du paramètre à l'antiferroma- gnétisme. Le composé défini MnBi est ferromagnétique; l'aimantation spontanée

  15. Plant embryogenesis requires AUX/LAX-mediated auxin influx.

    PubMed

    Robert, Hélène S; Grunewald, Wim; Sauer, Michael; Cannoot, Bernard; Soriano, Mercedes; Swarup, Ranjan; Weijers, Dolf; Bennett, Malcolm; Boutilier, Kim; Friml, Ji?í

    2015-02-15

    The plant hormone auxin and its directional transport are known to play a crucial role in defining the embryonic axis and subsequent development of the body plan. Although the role of PIN auxin efflux transporters has been clearly assigned during embryonic shoot and root specification, the role of the auxin influx carriers AUX1 and LIKE-AUX1 (LAX) proteins is not well established. Here, we used chemical and genetic tools on Brassica napus microspore-derived embryos and Arabidopsis thaliana zygotic embryos, and demonstrate that AUX1, LAX1 and LAX2 are required for both shoot and root pole formation, in concert with PIN efflux carriers. Furthermore, we uncovered a positive-feedback loop between MONOPTEROS (ARF5)-dependent auxin signalling and auxin transport. This MONOPTEROS-dependent transcriptional regulation of auxin influx (AUX1, LAX1 and LAX2) and auxin efflux (PIN1 and PIN4) carriers by MONOPTEROS helps to maintain proper auxin transport to the root tip. These results indicate that auxin-dependent cell specification during embryo development requires balanced auxin transport involving both influx and efflux mechanisms, and that this transport is maintained by a positive transcriptional feedback on auxin signalling. PMID:25617434

  16. PASSAGE OBLIGATOIRE AUX NORMES COMPTABLES IAS/IFRS, CONTRAINTES EN

    E-print Network

    Paris-Sud XI, Université de

    PASSAGE OBLIGATOIRE AUX NORMES COMPTABLES IAS/IFRS, CONTRAINTES EN LIQUIDITE ET RATIONNEMENT DU'adoption obligatoire par les banques des normes comptables IAS/IFRS, réputées d'une qualité supérieure pour la prise de obligatoire des normes comptables IAS/IFRS, conséquences économiques, banques, rationnement du crédit Abstract

  17. CULTURE IN VITRO DU ROTAVIRUS ASSOCI AUX DIARRHES

    E-print Network

    Paris-Sud XI, Université de

    CULTURE IN VITRO DU ROTAVIRUS ASSOCIÉ AUX DIARRHÉES NÉONATALES DU VEAU R. L'HARIDON R. SCHERRER) RÉSUMÉ Une cinquantaine d'échantillons de fèces diarrhéiques, contenant le rotavirus du veau en quantité. INTRODUCTION I,'association d'un rotavirus avec un fort pourcentage de cas de diarrhées néo- natales du veau en

  18. Bienvenue aux gays du monde entier . Tourisme gay et mondialisation

    E-print Network

    Paris-Sud XI, Université de

    - 1 - « Bienvenue aux gays du monde entier ». Tourisme gay et mondialisation Emmanuel JAURAND-94010 CRETEIL Résumé Le tourisme gay est le tourisme identitaire et communautaire des homosexuels rapport à la globalisation, le tourisme gay peut apparaître paradoxal. Il repose en partie sur des

  19. Application of a new Raman microprobe spectrometer to nondestructive analysis of sulfate and other ions in individual phases in fluid inclusions in minerals

    Microsoft Academic Search

    Gregory J. Rosasco; Edwin Roedder

    1979-01-01

    et al . (1975), reported the first successful application of laser-excited Raman spectroscopy for the identification and nondestructive partial analysis of individual solid, liquid, and gaseous phases in selected fluid inclusions. We report here the results of the application of a new instrument, based on back-scattering, that eliminates many of the previous stringent sample limitations and hence greatly expands the

  20. Extraction and preconcentration of tylosin from milk samples through functionalized TiO? nanoparticles reinforced with a hollow fiber membrane as a novel solid/liquid-phase microextraction technique.

    PubMed

    Sehati, Negar; Dalali, Nasser; Soltanpour, Shahla; Dorraji, Mir Saeed Seyed

    2014-08-01

    The aim of this study was to introduce a novel, simple, and highly sensitive preparation method for determination of tylosin in different milk samples. In the so-called functionalized TiO2 hollow fiber solid/liquid-phase microextraction method, the acceptor phase is functionalized TiO2 nanoparticles that are dispersed in the organic solvent and held in the pores and lumen of a porous polypropylene hollow fiber membrane. An effective functionalization of TiO2 nanoparticles has been done in the presence of aqueous H2 O2 and a mild acidic ambient under UV irradiation. This novel extraction method showed excellent extraction efficiency and a high enrichment factor (540.2) in comparison with conventional hollow fiber liquid-phase microextraction. All the experiments were monitored at ?max = 284 nm using a simple double beam UV-visible spectrophotometer. A Taguchi orthogonal array experimental design with an OA16 (4(5) ) matrix was employed to optimize the factors affecting the efficiency of hollow fiber solid/liquid-phase microextraction such as pH, stirring rate, salt addition, extraction time, and the volume of donor phase. This developed method was successfully applied for the separation and determination of tylosin in milk samples with a linear concentration range of 0.51-7000 ?g/L (r(2) = 0.991) and 0.21 ?g/L as the limit of detection. PMID:24890459

  1. Etude numrique des convertisseurs hliothermiques tubulaires. Application aux capteurs THEK

    E-print Network

    Paris-Sud XI, Université de

    ), des phénomènes de réflexions multiples tant pour le rayonnement solaire incident que pour le tubes, peints en noir, présentent un facteur d'absorption élevé pour le rayonnement solaire ; à « l'évaluation du champ des températures dans les absorbeurs placés au foyer de concentrateurs solaires de type THEK

  2. Expression and regulation of the early auxin-responsive Aux\\/IAA genes during strawberry fruit development

    Microsoft Academic Search

    Du-juan LiuJian-ye; Jian-ye Chen; Wang-jin Lu

    2011-01-01

    The plant hormone auxin transcriptionally activates Aux\\/IAA genes. Auxin plays an important role in regulating fruit growth and ripening of strawberry and Aux\\/IAA genes have been extensively studied in Arabidopsis, rice and tomato, but little information is available on strawberry fruit. In the present work, two full-length of early\\u000a auxin-responsive Aux\\/IAA genes, termed FaAux\\/IAA1 and FaAux\\/IAA2 respectively, were isolated and

  3. I -INTRODUCTION AUX STATISTIQUES J-P. Croisille

    E-print Network

    Croisille, Jean-Pierre

    I - INTRODUCTION AUX STATISTIQUES J-P. Croisille Universit´e de Lorraine UEL - Ann´ee 2012/2013 Jean-Pierre CROISILLE - Laboratoire LMAM UEL: L'influence des math´ematiques sur la soci´et´e #12´ees/multivari´ees Jean-Pierre CROISILLE - Laboratoire LMAM UEL: L'influence des math´ematiques sur la soci´et´e #12;Donn

  4. Introduction aux probabilites -L2 -annee 2004-2005

    E-print Network

    Pellier, Damien

    proc´eder par tirage au sort parmi tous les candidats, en attribuant un num´ero `a chacun d'entre eux. Les num´eros de de 1 `a n1 correspondent aux candidats de sexe f´eminin (masculin respectivement), les probabilit´e uniforme; la probabilit´e de tout ´ev´enement B de est donn´ee par P[B] = cardB card . A

  5. Structural characterization of the voltage sensor domain and voltage-gated K+- channel proteins vectorially-oriented within a single bilayer membrane at the solid/vapor and solid/liquid interfaces via neutron interferometry

    PubMed Central

    Gupta, S.; Dura, J.A.; Freites, J.A.; Tobias, D.J.; Blasie, J. K.

    2012-01-01

    The voltage-sensor domain (VSD) is a modular 4-helix bundle component that confers voltage sensitivity to voltage-gated cation channels in biological membranes. Despite extensive biophysical studies and the recent availability of x-ray crystal structures for a few voltage-gated potassium (Kv-) channels and a voltage-gate sodium (Nav-) channel, a complete understanding of the cooperative mechanism of electromechanical coupling, interconverting the closed-to-open states (i.e. non-conducting to cation conducting) remains undetermined. Moreover, the function of these domains is highly dependent on the physical-chemical properties of the surrounding lipid membrane environment. The basis for this work was provided by a recent structural study of the VSD from a prokaryotic Kv-channel vectorially-oriented within a single phospholipid (POPC; 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) membrane investigated by x-ray interferometry at the solid/moist He (or solid/vapor) and solid/liquid interfaces thus achieving partial to full hydration, respectively (Gupta et. al. Phys. Rev E. 2011, 84). Here, we utilize neutron interferometry to characterize this system in substantially greater structural detail at the sub-molecular level, due to its inherent advantages arising from solvent contrast variation coupled with the deuteration of selected sub-molecular membrane components, especially important for the membrane at the solid/liquid interface. We demonstrate the unique vectorial orientation of the VSD and the retention of its molecular conformation manifest in the asymmetric profile structure of the protein within the profile structure of this single bilayer membrane system. We definitively characterize the asymmetric phospholipid bilayer solvating the lateral surfaces of the VSD protein within the membrane. The profile structures of both the VSD protein and phospholipid bilayer depend upon the hydration state of the membrane. We also determine the distribution of water and exchangeable hydrogen throughout the profile structure of both the VSD itself and the VSD:POPC membrane. These two experimentally-determined water and exchangeable hydrogen distribution profiles are in good agreement with molecular dynamics simulations of the VSD protein vectorially-oriented within a fully hydrated POPC bilayer membrane, supporting the existence of the VSD’s water pore. This approach was extended to the full-length Kv-channel (KvAP) at solid/liquid interface, providing the separate profile structures of the KvAP protein and the POPC bilayer within the reconstituted KvAP:POPC membrane. PMID:22686684

  6. Des furoncles résistants aux antibiotiques: penser à la myiase !!

    PubMed Central

    Ajili, Faida; Abid, Rim; Bousseta, Najeh; Mrabet, Ali; Karoui, Ghazi; Louzir, Bassem; Battikh, Riadh; Othmani, Salah

    2013-01-01

    Les myiases sont des infections parasitaires par des larves de mouches. La localisation cutanée doit être évoquée de retour d'un pays tropical devant une évolution inhabituelle de lésions cutanées. Nous rapportons une observation d'un militaire tunisien, ayant séjourné en République Démocratique du Congo. Il était atteint de myiase cutanée simulatrice d'une furonculose résistante aux antibiotiques. L'intérêt de cette observation est de souligner l'importance d’évoquer la myiase dont le traitement est simple et rapide chez un patient de retour de zone d'endémie. PMID:24106569

  7. CIEAEM 57 Italie Italy Foire aux ides, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session

    E-print Network

    Spagnolo, Filippo

    CIEAEM 57 ­ Italie ­ Italy Foire aux idées, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session July 23-29, 2005 Foire aux idées, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session July 23-29, 2005

  8. CIEAEM 57 Italie Italy Foire aux ides, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session

    E-print Network

    Spagnolo, Filippo

    CIEAEM 57 ­ Italie ­ Italy Foire aux idées, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session July 23-29, 2005 ­ Italie ­ Italy Foire aux idées, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session July 23

  9. CIEAEM 57 Italie Italy Foire aux ides, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session

    E-print Network

    Spagnolo, Filippo

    CIEAEM 57 ­ Italie ­ Italy Foire aux idées, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session July 23-29, 2005: Solution 2: #12;CIEAEM 57 ­ Italie ­ Italy Foire aux idées, Session de Poster Piazza Armerina, Forum

  10. EFFET KERR ET LECTROSTRICTION DANS DES VERRES AUX SILICATES DE PLOMB

    E-print Network

    Paris-Sud XI, Université de

    855 EFFET KERR ET ÉLECTROSTRICTION DANS DES VERRES AUX SILICATES DE PLOMB M. PAILLETTE LaboratoireHz) et haute fréquence (5MHz) d'une série de verres aux silicates de plomb et de la silice vitreuse ont été mesurées à 6 328 Å et à température ambiante. Hormis deux verres, l'écart entre ces valeurs

  11. RICHARD SIMON ET LES JUIFS DU 17E SICLE Les juifs prsents aux chrtiens

    E-print Network

    Paris-Sud XI, Université de

    1 RICHARD SIMON ET LES JUIFS DU 17E SIÈCLE «Les juifs présentés aux chrétiens» Paul PAUMIER Professeur agrégé de l'Université de Rouen (GRHIS) Colloque Richard Simon (Rouen, samedi 13 octobre 2012) Dans cette communication je vais m'intéresser aux relations entre Richard SIMON 1 et les Juifs de son

  12. CHOIX D'OPTIONS COMPTABLES LORS DE LA TRANSITION AUX NORMES IAS/IFRS

    E-print Network

    Paris-Sud XI, Université de

    CHOIX D'OPTIONS COMPTABLES LORS DE LA TRANSITION AUX NORMES IAS/IFRS Samira DEMARIA et Dominique, intervenus lors de la transition aux normes comptables IAS/IFRS. Les apports de la Théorie Positive de la'hypothèses issues de la TPC. La méthode d'analyse statistique utilisée est la régression logistique. Mots clés : IAS/IFRS

  13. Publi dans Tiberghien, G. (1999). La psychologie cognitive survivra-t-elle aux sciences

    E-print Network

    Paris-Sud XI, Université de

    1999-01-01

    Publié dans Tiberghien, G. (1999). La psychologie cognitive survivra-t-elle aux sciences cognitives), 265-283. La psychologie cognitive survivra-t-elle aux sciences cognitives ? Guy Tiberghien Institut des Sciences Cognitives, Lyon · Bien que les sciences cognitives aient atteint en quelques décennies

  14. ducation aux TIC, cultures informatique et du numrique : quelques repres historiques

    E-print Network

    Paris-Sud XI, Université de

    Éducation aux TIC, cultures informatique et du numérique : quelques repères historiques Béatrice aussi au coeur de l'informatique. Si l'éducation aux technologies de l'information et de la, la définir aujourd'hui demande aussi de mieux cerner l' « objet » informatique, en l'ancrant dans une

  15. Several applications of a model for dense granular flows

    E-print Network

    Cawthorn, Christopher John

    2011-03-15

    aggregates. Furthermore, few children (at least in developed countries) will not, at some point in their lives, have sculpted castles, faces, or animals out of sand or snow. There are countless engineering applications involving granular materials, some... of granular flow by their analogy with solid, liquide, and gas-like behaviour, as appropriate. For example, a dense packing of grains exhibits the kind of structural rigidity commonly found in solid materials, yet grains poured vertically onto a surface can...

  16. Conséquences comportementales de la violence faite aux enfants

    PubMed Central

    Al Odhayani, Abdulaziz; Watson, William J.; Watson, Lindsay

    2013-01-01

    Résumé Objectif Discuter des répercussions de la violence sur le développement comportemental durant l’enfance, mettre en évidence certains signes comportementaux susceptibles d’alerter les médecins à la présence d’une maltraitance continue d’un enfant et explorer le rôle précis du médecin de famille dans une telle situation clinique. Sources des données Une recension systématique a servi à examiner la recherche pertinente, les articles de révision clinique et les sites web des organismes de protection de la jeunesse. Message principal Le comportement d’un enfant est une manifestation extériorisée de sa stabilité et de sa sécurité intérieures. C’est une lentille au travers de laquelle le médecin de famille peut observer le développement de l’enfant pendant toute sa vie. Tous les genres de violence sont dommageables pour les enfants, qu’elle soit physique, affective ou psychologique, et peuvent causer des problèmes à long terme dans le développement du comportement et de la santé mentale. Les médecins de famille doivent connaître les indices de maltraitance et de négligence envers les enfants et être aux aguets de ces derniers afin d’entreprendre les interventions appropriées et améliorer les résultats pour ces enfants. Conclusion La violence faite aux enfants peut causer un développement psychologique désordonné et des problèmes de comportement. Les médecins de famille exercent un rôle important dans la reconnaissance des signes comportementaux laissant présager une maltraitance, ainsi que pour offrir de l’aide afin de protéger les enfants.

  17. Ajustements nationaux de mcanismes prix face aux fluctuations du prix mondial : les leons du coton en Afrique Zone Franc

    E-print Network

    Paris-Sud XI, Université de

    Ajustements nationaux de mécanismes prix face aux fluctuations du prix mondial : les leçons du, à l'instauration d'un mécanisme de prix d'achat aux paysans intégrant l'adaptation aux fluctuations du prix mondial. Depuis 1985, la résurgence de baisses du prix mondial, de grande ampleur et à grande

  18. Doping effect on the Janus-like structure of a copper-iron bimetallic nanocluster and its solid-liquid phase transition

    NASA Astrophysics Data System (ADS)

    Taherkhani, Farid; Seresht, Pegah Freshteh

    2015-04-01

    A molecular dynamics simulation with a new-application potential model has been explored for melting temperature, radial distribution of iron-copper bimetallic nanoclusters, and their bulk for the first time. At low copper weight percentages, the melting temperature changes a little for the bulk structures; however, for nanostructures, the variation of melting temperature is significant. At medium copper-doping values, there is a melting-temperature plateau in bimetallic nanoclusters. For many catalysis applications, Janus-like structures are considered, which occur at around 53% iron weight in copper at room temperature, when copper-iron bimetallic nanoclusters clearly consist of two distinct faces. Our result for the melting temperature of the bulk alloy confirms the experimental result.

  19. AUX/LAX genes encode a family of auxin influx transporters that perform distinct functions during Arabidopsis development.

    PubMed

    Péret, Benjamin; Swarup, Kamal; Ferguson, Alison; Seth, Malvika; Yang, Yaodong; Dhondt, Stijn; James, Nicholas; Casimiro, Ilda; Perry, Paula; Syed, Adnan; Yang, Haibing; Reemmer, Jesica; Venison, Edward; Howells, Caroline; Perez-Amador, Miguel A; Yun, Jeonga; Alonso, Jose; Beemster, Gerrit T S; Laplaze, Laurent; Murphy, Angus; Bennett, Malcolm J; Nielsen, Erik; Swarup, Ranjan

    2012-07-01

    Auxin transport, which is mediated by specialized influx and efflux carriers, plays a major role in many aspects of plant growth and development. AUXIN1 (AUX1) has been demonstrated to encode a high-affinity auxin influx carrier. In Arabidopsis thaliana, AUX1 belongs to a small multigene family comprising four highly conserved genes (i.e., AUX1 and LIKE AUX1 [LAX] genes LAX1, LAX2, and LAX3). We report that all four members of this AUX/LAX family display auxin uptake functions. Despite the conservation of their biochemical function, AUX1, LAX1, and LAX3 have been described to regulate distinct auxin-dependent developmental processes. Here, we report that LAX2 regulates vascular patterning in cotyledons. We also describe how regulatory and coding sequences of AUX/LAX genes have undergone subfunctionalization based on their distinct patterns of spatial expression and the inability of LAX sequences to rescue aux1 mutant phenotypes, respectively. Despite their high sequence similarity at the protein level, transgenic studies reveal that LAX proteins are not correctly targeted in the AUX1 expression domain. Domain swapping studies suggest that the N-terminal half of AUX1 is essential for correct LAX localization. We conclude that Arabidopsis AUX/LAX genes encode a family of auxin influx transporters that perform distinct developmental functions and have evolved distinct regulatory mechanisms. PMID:22773749

  20. TUDE DES TRANSITIONS ENTRE TATS MTALLIQUES ET ISOLANTS. APPLICATION AUX BANDES D'IMPURET ET AUX ANTIFERROMAGNTIQUES. II.

    E-print Network

    Paris-Sud XI, Université de

    Under definite assumptions, an electron gas in a solid may behave as an insulator, in contradiction'hamil- tonien diagonal. Comme nous le verrons, tout se passe comme si notre transformation antiferro- magnétique

  1. Function of the aux and rol genes of the Ri plasmid in plant cell division in vitro.

    PubMed

    Nemoto, Keiichirou; Hara, Masamitsu; Suzuki, Masashi; Seki, Hikaru; Oka, Atsuhiro; Muranaka, Toshiya; Mano, Yoshihiro

    2009-12-01

    Auxin-autonomous growth in vitro may be related to the integration and expression of the aux and rol genes from the root-inducing (Ri) plasmid in plant cells infected by agropine-type Agrobacterium rhizogenes. To elucidate the functions of the aux and rol genes in plant cell division, plant cell lines transformed with the aux1 and aux2 genes or with the rolABCD genes were established using tobacco (Nicotiana tabacum) Bright Yellow-2 (BY-2) cells. The introduction of the aux1 and aux2 genes enabled the auxin-autonomous growth of BY-2 cells, but the introduction of the rolABCD genes did not affect the auxin requirement of the BY-2 cells. The results clearly show that the aux genes are necessary for auxinautotrophic cell division, and that the rolABCD genes are irrelevant in auxin autotrophy. PMID:20514230

  2. Function of the aux and rol genes of the Ri plasmid in plant cell division in vitro

    PubMed Central

    Nemoto, Keiichirou; Hara, Masamitsu; Suzuki, Masashi; Seki, Hikaru; Oka, Atsuhiro; Muranaka, Toshiya

    2009-01-01

    Auxin-autonomous growth in vitro may be related to the integration and expression of the aux and rol genes from the root-inducing (Ri) plasmid in plant cells infected by agropine-type Agrobacterium rhizogenes. To elucidate the functions of the aux and rol genes in plant cell division, plant cell lines transformed with the aux1 and aux2 genes or with the rolABCD genes were established using tobacco (Nicotiana tabacum) Bright Yellow-2 (BY-2) cells. The introduction of the aux1 and aux2 genes enabled the auxin-autonomous growth of BY-2 cells, but the introduction of the rolABCD genes did not affect the auxin requirement of the BY-2 cells. The results clearly show that the aux genes are necessary for auxinautotrophic cell division, and that the rolABCD genes are irrelevant in auxin autotrophy. PMID:20514230

  3. Enzymatic probe sonication as a tool for solid–liquid extraction for total selenium determination by electrothermal-atomic absorption spectrometry

    Microsoft Academic Search

    G. Vale; S. Pereira; A. Mota; L. Fonseca; J. L. Capelo

    2007-01-01

    A new fast and reproducible approach is described for the application of the enzymatic probe sonication (EPS) methodology [J.L. Capelo, P. Ximénez-Embún, Y. Madrid-Albarrán, C. Cámara, Anal. Chem. 76 (2004) 233–237] for total selenium determination by electrothermal atomic absorption spectrometry, ET-AAS. Ni(NO3)2 and Pd(NO3)2 were studied as matrix modifiers in conjunction with H2O2, being best results obtained with Pd(NO3)2 plus

  4. Separation-preconcentration of nickel and lead in food samples by a combination of solid-liquid-solid dispersive extraction using SiO2 nanoparticles, ionic liquid-based dispersive liquid-liquid micro-extraction.

    PubMed

    Jalbani, Nusrat; Soylak, Mustafa

    2015-01-01

    A microextraction method for the determination of nickel and lead using solid-liquid-solid dispersive extraction followed by ionic liquid-based dispersive liquid-liquid microextraction (SLSDE-ILDLLME) was presented. It was applied to the extraction of nickel and lead from food samples. Ammonium pyrrolidine dithiocarbamate (APDC) as complexing agent, [C4MIM][PF6] as ionic liquid, SiO2 as nanoparticles and 2 mol L(-1) HNO3 as eluent were used. Several important parameters such as amount of IL, extraction time, pH and volume of the complexing agent were investigated. The quantitative recoveries were obtained at pH 7.0 for analytes. Under the optimum conditions, the limits of detection (LODs) calculated using 3(Sd)blank/m were 0.17 for Ni(II) and 0.79 µg L(-1) for Pb(II) for aqueous solutions with 125 enrichment factor (EF). The limit of detections of the analyte ions (3(Sd)blank/m) for solid samples were 0.09 µg g(-1) (Ni) and 0.40 µg g(-1) (Pb). The accuracy of the proposed method was confirmed by the analysis of standard reference material (1577c bovine liver) and spiked recovery test. The proposed method was applied to determine nickel and lead levels in chicken, fish and meat samples. PMID:25281115

  5. Determination of perfluorinated alkyl acids in corn, popcorn and popcorn bags before and after cooking by focused ultrasound solid-liquid extraction, liquid chromatography and quadrupole-time of flight mass spectrometry.

    PubMed

    Moreta, Cristina; Tena, María Teresa

    2014-08-15

    An analytical method is proposed to determine ten perfluorinated alkyl acids (PFAAs) [nine perfluorocarboxylic acids (PFCAs) and perfluorooctane sulfonate (PFOS)] in corn, popcorn and microwave popcorn packaging by focused ultrasound solid-liquid extraction (FUSLE) and ultra high performance liquid chromatography (UHPLC) coupled to quadrupole-time of flight mass spectrometry (QTOF-MS/MS). Selected PFAAs were extracted efficiently in only one 10-s cycle by FUSLE, a simple, safe and inexpensive technique. The developed method was validated for microwave popcorn bags matrix as well as corn and popcorn matrices in terms of linearity, matrix effect error, detection and quantification limits, repeatability and recovery values. The method showed good accuracy with recovery values around 100% except for the lowest chain length PFAAs, satisfactory reproducibility with RSDs under 16%, and sensitivity with limits of detection in the order of hundreds picograms per gram of sample (between 0.2 and 0.7ng/g). This method was also applied to the analysis of six microwave popcorn bags and the popcorn inside before and after cooking. PFCAs contents between 3.50ng/g and 750ng/g were found in bags, being PFHxA (perfluorohexanoic acid) the most abundant of them. However, no PFAAs were detected either corn or popcorn, therefore no migration was assumed. PMID:24986069

  6. Preliminary paleogeographic reconstruction of the Illinois basin during deposition of the Mississippian Aux Vases Formation: Implications for hydrocarbon recovery

    SciTech Connect

    Cole, R.D. (Illinois State Geological Survey, Champaign (United States))

    1991-03-01

    Extensive outcrop investigation and selective subsurface study allow definition of Illinois basin paleogeography during deposition of the Mississippian (Valmeyeran-Meramecian) Aux Vases Formation. The results incorporate an integrated approach utilizing field observations and petrographic analysis, wireline logs, subsurface maps, and cores. The Aux Vases Formation depositional system has been determined to be composed of subtidal to intertidal facies. Depositional facies in outcrop are based on rock body geometries, sedimentary structure assemblages, paleocurrent analysis, paleontology of body and trace fossils, facies relationships, and petrography. Depositional facies determined from subsurface data are based on correlation of lithologic interpretations from wireline logs, sand body geometries form isopach maps, and petrography. Specific depositional facies observed in outcrop and core and inferred from wireline logs and isopach maps are offshore bars and tidal channel complexes, extensive subtidal to lower intertidal, ripple-laminated, fine-grained quartzose sandstone. Carbonate facies occur as subtidal grainstones at or near the base of a sequence, or as high energy deposits which have been tidally reworked. This depositional system produces reservoir heterogeneities that complicate efficient hydrocarbon recovery. This diverse facies architecture is modified by tectonic and diagenetic overprinting, further segregating potential producing zones. To significantly improve recovery efficiency, predictions regarding compartmentalization can be used prior to designing a drilling program, an infill drilling program, or an application of enhanced recovery techniques.

  7. Enzymatic probe sonication as a tool for solid-liquid extraction for total selenium determination by electrothermal-atomic absorption spectrometry.

    PubMed

    Vale, G; Pereira, S; Mota, A; Fonseca, L; Capelo, J L

    2007-11-30

    A new fast and reproducible approach is described for the application of the enzymatic probe sonication (EPS) methodology [J.L. Capelo, P. Ximénez-Embún, Y. Madrid-Albarrán, C. Cámara, Anal. Chem. 76 (2004) 233-237] for total selenium determination by electrothermal atomic absorption spectrometry, ET-AAS. Ni(NO3)2 and Pd(NO3)2 were studied as matrix modifiers in conjunction with H2O2, being best results obtained with Pd(NO3)2 plus H2O2. The presence of H2O2 as matrix modifier increases up to 66% the time-life of the graphite tubes, by avoiding the building-up of carbonaceous residues. BCR-414 plankton and ERM-CE 278 mussel tissue reference materials were used for proof-of-the-methodology. Different enzymes, protease XIV, substilisin and trypsin were studied. The use of fresh enzyme was found critical. Good Se recoveries were obtained for oyster tissue, 111%; BCR-414 plankton, 106% and ERM-CE 278 mussel tissue, 93%, when protease XIV was used. Data regarding microwave digestion versus EPS methodology is also presented and discussed. PMID:18371630

  8. A Mn-54 radiotracer study of Mn isotope solid-liquid exchange during reductive transformation of vernadite (?-MnO2) by aqueous Mn(II).

    PubMed

    Elzinga, Evert J; Kustka, Adam B

    2015-04-01

    We employed Mn-54 radiotracers to characterize the extent and dynamics of Mn atom exchange between aqueous Mn(II) and vernadite (?-Mn(IV)O2) at pH 7.5 under anoxic conditions. Exchange of Mn atoms between the solid and liquid phase is rapid, reaching dynamic equilibrium in 2-4 days. We propose that during the initial stages of reaction, Mn atom exchange occurs through consecutive comproportionation-disproportionation reactions where interfacial electron transfer from adsorbed Mn(II) to lattice Mn(IV) generates labile Mn(III) cations that rapidly disproportionate to reform aqueous Mn(II) and solid-phase Mn(IV). Following nucleation of Mn(III)OOH phases, additional exchange likely occurs through electron transfer from aqueous Mn(II) to solid-phase Mn(III). Our results provide evidence for the fast and extensive production of transient Mn(III) species at the vernadite surface upon contact of this substrate with dissolved Mn(II). We further show that HEPES buffer is a reductant of lattice Mn(IV) in the vernadite structure in our experiments. The methods and results presented here introduce application of Mn-54 tracers as a facile tool to further investigate the formation kinetics of labile Mn(III) surface species and their impacts on Mn-oxide structure and reactivity over a range of environmentally relevant geochemical conditions. PMID:25751090

  9. A gas-diffusion flow injection method coupled with online solid-liquid extraction for the determination of ammonium in solid samples.

    PubMed

    Timofeeva, Irina I; Bulatov, Andrey V; Moskvin, Aleksey L; Kolev, Spas D

    2015-09-01

    A simple, rapid and reliable gas-diffusion flow injection (GD-FI) method for ammonium determination in building materials has been developed. It is based on leaching ammonium from a ground solid sample into an alkaline solution with subsequent ammonia gas generation. Ammonia is then transported in a nitrogen stream to the GD cell of the FI system where it is absorbed into its acceptor solution containing a mixture of the acid-base indicators cresol red and thymol blue. The maximum increase in the absorbance of the acceptor solution at 580nm is related to the ammonium concentration in the solid sample. The proposed method is characterized by a linear concentration range of 0.1-5.0mgNH4(+)kg(-1), a limit of detection of 8?gNH4(+)kg(-1) and a sample throughput of 10h(-1). A successful application of this method for the determination of ammonium in building materials such as concrete, cement and sand is reported. PMID:26003703

  10. Outils d'acces aux donnees d'un PLC "Automate Web Access (AWA)"

    E-print Network

    Palluel, J; CERN. Geneva. AB Department

    2004-01-01

    Cette note presente un moniteur d'acces aux donnees d'un PLC Schneider ou Siemens, pouvant fonctionner sur n'importe quelle plateforme (Windows, Linux...) equipee d'un navigateur WEB sans telechargement de logiciel ("Applets").

  11. L'EUROPE CENTRALE AUX XVIIE-XIXE SICLES : REPRSENTATIONS ET ENJEUX AU XXE SICLE

    E-print Network

    Paris-Sud XI, Université de

    ------------------------------------------------------------------------------------- L'EUROPE Gradvohl (dir.), L'Europe médiane au XXe siècle. Fractures, décompositions ­ recompositions-80-86311-23-4 ------------------------------------------------------------------------------------- Pour citer cet article : François PERNOT, « L'Europe centrale aux XVIIe-XIXe siècles : représentations

  12. Protein-protein interaction and gene co-expression maps of ARFs and Aux/IAAs in Arabidopsis.

    PubMed

    Piya, Sarbottam; Shrestha, Sandesh K; Binder, Brad; Stewart, C Neal; Hewezi, Tarek

    2014-01-01

    The phytohormone auxin regulates nearly all aspects of plant growth and development. Based on the current model in Arabidopsis thaliana, Auxin/indole-3-acetic acid (Aux/IAA) proteins repress auxin-inducible genes by inhibiting auxin response transcription factors (ARFs). Experimental evidence suggests that heterodimerization between Aux/IAA and ARF proteins are related to their unique biological functions. The objective of this study was to generate the Aux/IAA-ARF protein-protein interaction map using full length sequences and locate the interacting protein pairs to specific gene co-expression networks in order to define tissue-specific responses of the Aux/IAA-ARF interactome. Pairwise interactions between 19 ARFs and 29 Aux/IAAs resulted in the identification of 213 specific interactions of which 79 interactions were previously unknown. The incorporation of co-expression profiles with protein-protein interaction data revealed a strong correlation of gene co-expression for 70% of the ARF-Aux/IAA interacting pairs in at least one tissue/organ, indicative of the biological significance of these interactions. Importantly, ARF4-8 and 19, which were found to interact with almost all Aux-Aux/IAA showed broad co-expression relationships with Aux/IAA genes, thus, formed the central hubs of the co-expression network. Our analyses provide new insights into the biological significance of ARF-Aux/IAA associations in the morphogenesis and development of various plant tissues and organs. PMID:25566309

  13. Le succès des cultures transgéniques aux États-Unis: facteurs agro-économiques et perspectives

    Microsoft Academic Search

    Sylvie Bonny

    2002-01-01

    [fre] A partir du cas du soja tolérant à l'herbicide gly- phosate, l'article analyse un certain nombre de facteurs expliquant la progression rapide des cultures transgéniques aux USA. Après avoir passé en revue leurs surfaces dans le monde et aux USA, on examine divers facteurs agro-économiques à l'origine de la diffusion rapide du soja tolérant au glyphosate dans les exploitations

  14. Prospects for laser-induced breakdown spectroscopy for biomedical applications: a review

    Microsoft Academic Search

    Vivek Kumar Singh; Awadhesh Kumar Rai

    2011-01-01

    We review the different spectroscopic techniques including the most recent laser-induced breakdown spectroscopy (LIBS) for\\u000a the characterization of materials in any phase (solid, liquid or gas) including biological materials. A brief history of the\\u000a laser and its application in bioscience is presented. The development of LIBS, its working principle and its instrumentation\\u000a (different parts of the experimental set up) are

  15. In Situ Adsorption Studies at the Solid/Liquid Interface:Characterization of Biological Surfaces and Interfaces Using SumFrequency Generation Vibrational Spectroscopy, Atomic Force Microscopy,and Quartz Crystal Microbalance

    SciTech Connect

    Phillips, D.C.

    2006-05-16

    Sum frequency generation (SFG) vibrational spectroscopy, atomic force microscopy (AFM), and quartz crystal microbalance (QCM) have been used to study the molecular surface structure, surface topography and mechanical properties, and quantitative adsorbed amount of biological molecules at the solid-liquid interface. The molecular-level behavior of designed peptides adsorbed on hydrophobic polystyrene and hydrophilic silica substrates has been examined as a model of protein adsorption on polymeric biomaterial surfaces. Proteins are such large and complex molecules that it is difficult to identify the features in their structure that lead to adsorption and interaction with solid surfaces. Designed peptides which possess secondary structure provide simple model systems for understanding protein adsorption. Depending on the amino acid sequence of a peptide, different secondary structures ({alpha}-helix and {beta}-sheet) can be induced at apolar (air/liquid or air/solid) interfaces. Having a well-defined secondary structure allows experiments to be carried out under controlled conditions, where it is possible to investigate the affects of peptide amino acid sequence and chain length, concentration, buffering effects, etc. on adsorbed peptide structure. The experiments presented in this dissertation demonstrate that SFG vibrational spectroscopy can be used to directly probe the interaction of adsorbing biomolecules with a surface or interface. The use of well designed model systems aided in isolation of the SFG signal of the adsorbing species, and showed that surface functional groups of the substrate are sensitive to surface adsorbates. The complementary techniques of AFM and QCM allowed for deconvolution of the effects of surface topography and coverage from the observed SFG spectra. Initial studies of biologically relevant surfaces are also presented: SFG spectroscopy was used to study the surface composition of common soil bacteria for use in bioremediation of nuclear waste.

  16. Enzyme adsorption at solid-liquid interfaces

    Microsoft Academic Search

    S. Duinhoven

    1992-01-01

    Enzymes are proteins with the capacity of catalysing various reactions. Nowadays two types of enzymes, proteases and lipases, are available for use in detergent formulations for household and industrial laundry washing. Proteases are capable of catalysing the hydrolysis of proteins while lipases enable the hydrolysis of glycerol esters, the main component in fats and non-mineral oils. In this study, two

  17. Penny Perfect Properties (Solid-Liquid Interactions)

    NSDL National Science Digital Library

    CREAM GK-12 Program, Engineering Education Research Center, College of Engineering and Architecture,

    Students investigate the property dependence between liquid and solid interfaces and determine observable differences in how liquids react to different solid surfaces. They compare copper pennies and plastic "coins" as the two test surfaces. Using an eye dropper to deliver various fluids onto the surfaces, students determine the volume and mass of a liquid that can sit on the surface. They use rulers, scales, equations of volume and area, and other methods of approximation and observation, to make their own graphical interpretations of trends. They apply what they learned to design two super-surfaces (from provided surface treatment materials) that arecapable of holding the most liquid by volume and by mass. Cost of materials is a parameter in their design decisions.

  18. Ultrasonic characterisation of solid-liquid suspensions

    Microsoft Academic Search

    G. Guidarelli; F. Craciun; C. Galassi; E. Roncari

    1998-01-01

    Results on ultrasonic attenuation in suspensions of alumina powder in water at high concentration (40% vol.) are presented. When high concentrations of solid material in the host liquid are desired, it is very important to keep the solid particles well separated (deflocculated). This property is achieved by using a dispersant, whose concentration is critical for obtaining a good particle separation.

  19. Copolymers at the solid-liquid interface

    Microsoft Academic Search

    C. M. Wijmans

    1994-01-01

    Copolymers consisting of both adsorbing and nonadsorbing segments can show an adsorption behaviour which is very different from that of homopolymers. We have mainly investigated the adsorption of AB diblock copolymers, which have one adsorbing block (anchor) and one nonadsorbing block (buoy). The anchors adsorb from solution onto a surface and the buoys protrude into the solution, Thus, a polymer

  20. Simultaneous determination of a variety of endocrine disrupting compounds in carrot, lettuce and amended soil by means of focused ultrasonic solid-liquid extraction and dispersive solid-phase extraction as simplified clean-up strategy.

    PubMed

    Mijangos, L; Bizkarguenaga, E; Prieto, A; Fernández, L A; Zuloaga, O

    2015-04-10

    The present study is focused on the development of an analytical method based on focused ultrasonic solid-liquid extraction (FUSLE) followed by dispersive solid-phase extraction (dSPE) clean-up and liquid chromatography-triple quadrupole tandem mass spectrometry (LC-MS/MS) optimised for the simultaneous analysis of certain endocrine disrupting compounds (EDCs), including alkylphenols (APs), bisphenol A (BPA), triclosan (TCS) and several hormones and sterols in vegetables (lettuce and carrot) and amended soil samples. Different variables affecting the chromatographic separation, the electrospray ionisation and mass spectrometric detection were optimised in order to improve the sensitivity of the separation and detection steps. Under the optimised extraction conditions (sonication of 5min at 33% of power with pulse times on of 0.8s and pulse times off of 0.2s in 10mL of n-hexane:acetone (30:70, v:v) mixture using an ice bath), different dSPE clean-up sorbents, such as Florisil, Envi-Carb, primary-secondary amine bonded silica (PSA) and C18, or combinations of them were evaluated for FUSLE extracts before LC-MS/MS. Apparent recoveries and precision in terms of relative standard deviation (RSDs %) of the method were determined at two different fortification levels (according to the matrix and the analyte) and values in the 70-130% and 2-27% ranges, respectively, were obtained for most of the target analytes and matrices. Matrix-matched calibration approach and the use of labelled standards as surrogates were needed for the properly quantification of most analytes and matrices. Method detection limits (MDLs), estimated with fortified samples, in the ranges of 0.1-100ng/g for carrot, 0.2-152ng/g for lettuce and 0.9-31ng/g for amended soil were obtained. The developed methodology was applied to the analysis of 11 EDCs in both real vegetable bought in a local market and in compost (from a local wastewater treatment plant, WWTP) amended soil samples. PMID:25746759

  1. Evidence supporting an intentional Neandertal burial at La Chapelle-aux-Saints

    PubMed Central

    Rendu, William; Beauval, Cédric; Crevecoeur, Isabelle; Bayle, Priscilla; Balzeau, Antoine; Bismuth, Thierry; Bourguignon, Laurence; Delfour, Géraldine; Faivre, Jean-Philippe; Lacrampe-Cuyaubère, François; Tavormina, Carlotta; Todisco, Dominique; Turq, Alain; Maureille, Bruno

    2014-01-01

    The bouffia Bonneval at La Chapelle-aux-Saints is well known for the discovery of the first secure Neandertal burial in the early 20th century. However, the intentionality of the burial remains an issue of some debate. Here, we present the results of a 12-y fieldwork project, along with a taphonomic analysis of the human remains, designed to assess the funerary context of the La Chapelle-aux-Saints Neandertal. We have established the anthropogenic nature of the burial pit and underlined the taphonomic evidence of a rapid burial of the body. These multiple lines of evidence support the hypothesis of an intentional burial. Finally, the discovery of skeletal elements belonging to the original La Chapelle aux Saints 1 individual, two additional young individuals, and a second adult in the bouffia Bonneval highlights a more complex site-formation history than previously proposed. PMID:24344286

  2. Sections efficaces absolues de l'ozone 298 K aux longueurs d'onde de la lampe au mercure

    E-print Network

    Boyer, Edmond

    for the absorption cross- sections of ozone at the mercury lamp wavelengths, specially for the calibrationL-105 Sections efficaces absolues de l'ozone à 298 K aux longueurs d'onde de la lampe au mercure'importance que présente la connaissance des sections efficaces de l'ozone aux longueurs d'onde de la lampe au

  3. Analyse texturale de l'criture Arabe multifonte de Gabor aux contourlets Analyse texturale de l'criture Arabe multifonte

    E-print Network

    Paris-Sud XI, Université de

    Analyse texturale de l'écriture Arabe multifonte de Gabor aux contourlets Analyse texturale de l'écriture Arabe multifonte de Gabor aux Contourlets Nadia Ben Amor1 ­ Najoua Essoukri Ben Amara2 1 Ecole Nationale.benamara@eniso.rnu.tn Résumé : La reconnaissance automatique de l'écriture Arabe reste encore un domaine intéressant d

  4. Principes fondamentaux de la nouvelle politique slave Appel aux peuples slaves par un patriote russe (et variantes)

    E-print Network

    Paris-Sud XI, Université de

    Annexes : Principes fondamentaux de la nouvelle politique slave Appel aux peuples slaves par un patriote russe (et variantes) Appel aux Slaves par un patriote russe La situation en Russie Ma défense halshs-00394269,version1-12May2010 #12;[1] Principes fondamentaux de la nouvelle politique slave1 Après

  5. Les choix d'options comptables lors de la transition aux normes IAS/IFRS : quel rle pour la prudence ?

    E-print Network

    Paris-Sud XI, Université de

    1 Les choix d'options comptables lors de la transition aux normes IAS/IFRS : quel rôle pour la comptables, des groupes du SBF 120, intervenus lors de la transition aux normes comptables IAS/IFRS. Les la régression logistique. Mots clés : IAS/IFRS, Transition, Choix d'options comptables, Théorie

  6. (Solid + liquid) equilibria and solid compound formation in ( N -methyl-2-pyrrolidinone + benzene, or toluene, or 1,3,5-trimethylbenzene, or ethylbenzene, or chlorobenzene, or 1,2-dichlorobenzene, or 1,2,4-trichlorobenzene, or 1,1,1-trichloroethane, or dichloromethane)

    Microsoft Academic Search

    Trevor M. Letcher

    2000-01-01

    (Solid + liquid) phase diagrams have been determined for (N -methyl-2-pyrrolidinone + benzene, or toluene, or 1,3,5-trimethylbenzene, or ethylbenzene, or chlorobenzene, or 1,2-dichlorobenzene, or 1,2,4-trichlorobenzene, or 1,1,1-trichloroethane, or dichloromethane). Solid addition compounds form with the empirical formulae: { (C5H9NO)2· C6H6}, (C5H9NO · 2ClC6H5),(C5H6NO · Cl2C6H4) ,(2C5H9NO · Cl3C6H3) . All are congruently melting compounds. Compound formation is attributed to a

  7. Mmoire prsent dans le cadre du chantier sur l'aide financire aux

    E-print Network

    Charette, André

    l'enseignement supérieur au Québec, notre population étudiante est en effet devenue de plus en plus'améliorer plus globalement le fonctionnement de l'AFE. Enfin, dans une troisième section, nous aborderons les'accessibilité financière aux études. Bien qu'un peu plus éloigné du mandat de 1 Ministère de l'enseignement supérieur, de

  8. Liaison spcifique du cortisol aux protines plasmatiques chez le Cobaye, de la naissance au sevrage

    E-print Network

    Boyer, Edmond

    Liaison spécifique du cortisol aux protéines plasmatiques chez le Cobaye, de la naissance au Aubière, France. Summary. Specific binding of cortisol to plasma protein in the guinea-pig from birth : - the concentration of plasma cortisol by competitive binding to protein ; - the association constant, Ka, and total

  9. Modelisation des Co-Expositions aux Pesticides : une Approche Bayesienne Nonparametrique

    E-print Network

    Paris-Sud XI, Université de

    Modelisation des Co-Expositions aux Pesticides : une Approche Bay´esienne Nonparam´etrique Am analysis framework. The goal is to determine mixture of pesticides residues which are simultaneously of pesticides is assessed from the available consumption data and contamination analyses. We propose to model

  10. Apport de l'ingnierie ontologique aux environnements de formation distance

    E-print Network

    Paris-Sud XI, Université de

    for ontological engineering. MOTS-CLES. ontologie, ingénierie ontologique, formation à distance, KEYWORDS.ontology, ontological engineering, distance education #12;STICEF/Hors série 2003, Technologies et formation à distance 11 Apport de l'ingénierie ontologique aux environnements de formation à distance Contribution

  11. Aide aux dplacements l'tranger des enseignants-chercheurs de l'Universit du Maine

    E-print Network

    Di Girolami, Cristina

    Aide aux déplacements à l'étranger des enseignants-chercheurs de l'Université du Maine retour'Université du Maine Le Service Recherche et le Service des Relations Internationales ont mis en place un-chercheurs, chercheurs et doctorants des laboratoires de l'Université du Maine. Il s'agit d'une aide strictement soumise

  12. SIMULATION DE L'VOLUTION DU CLIMAT AUX CHELLES GLOBALES ET RGIONALES

    E-print Network

    Boyer, Edmond

    SIMULATION DE L'ÉVOLUTION DU CLIMAT AUX ÉCHELLES GLOBALES ET RÉGIONALES Climate change at global exercice coordonné de simulation de l'évolution du climat au cours du 20e et du 21e siècle. Nous Panel on Climate Change (IPCC) that should appear in early 2007, modelling groups worldwide have

  13. Graphisme tactile appliqu aux illustrations de manuels scolaires l'usage d'enfants

    E-print Network

    Hayward, Vincent

    Graphisme tactile appliqué aux illustrations de manuels scolaires à l'usage d'enfants ayant une illustrations de manuels scolaires. Le logiciel MaskGen a été développé afin de transformer interactivement ces illustrations en graphiques tactiles. Une méthodologie a été développée pour transposer ces graphiques et les

  14. Simulation et prvision de la qualit de l'air aux chelles continentale et rgionale.

    E-print Network

    Ribes, Aurélien

    Simulation et prévision de la qualité de l'air aux échelles continentale et régionale. Anne Dufour ............ Episode de pollution à l'ozone en PACA 14 au 17 juillet 2006 Observations BASTER et Prévisions MOCAGE 40 problproblproblproblèèèèmemememe local etlocal etlocal etlocal et planplanplanplanéééétairetairetairetaire Episode de pollution à

  15. LE RECOURS CROISSANT AUX EVALUATEURS EXTERNES DANS LE CADRE DES NORMES IFRS : CONSEQUENCES POURL'AUDITEUR

    E-print Network

    Paris-Sud XI, Université de

    1 LE RECOURS CROISSANT AUX EVALUATEURS EXTERNES DANS LE CADRE DES NORMES IFRS : CONSEQUENCES POURL des normes IFRS pour les grands groupes cotés français, a provoqué l'apparition d'un nouvel acteur : l : auditeurs, évaluateurs externes, indépendance, allocation du coût d'acquisition, normes IFRS. Abstract

  16. Financiarisation, Evaluation et Information Comptable : De la cration de valeur aux IFRS

    E-print Network

    Paris-Sud XI, Université de

    1 Financiarisation, Evaluation et Information Comptable : De la création de valeur aux IFRS Journée IFRS Keywords : Financialization, shareholders value creation, EVA, IFRS standards Les règles normes IFRS fondées sur la valorisation des actifs à la valeur de marché. Une telle cohérence peut être

  17. L'apport d'internet aux Petites Entreprises (PE) touristiques dans la construction de leur

    E-print Network

    Paris-Sud XI, Université de

    RIPME L'apport d'internet aux Petites Entreprises (PE) touristiques dans la construction de leur Entreprises (PE) touristiques dans la construction de leur positionnement stratégique : le cas des hébergeurs les PE demeure faible (Eurostat 2010) et pourtant parmi les ap- plications IT, internet est pour les

  18. Le passage aux Normes internationales : de nouvelles options pour la gestion du résultat ?

    Microsoft Academic Search

    Karim Kharrat

    2006-01-01

    Les sociétés européenne cotées ont dû adopter au premier janvier 2005 toutes les Normes et interprétations de l'IASB (Normes IAS \\/ IFRS ). Le passage à ces Normes offre aux entreprises plusieurs options comptables et maintient une large part d'interprétation. Ces options et estimations se sont manifestées soit pour les besoins de la transition (retraitement ou non des acquisitions antérieures,

  19. Effet Mssbauer et techniques complmentaires : L'EXAFS appliqu aux dterminations structurales de milieux

    E-print Network

    Paris-Sud XI, Université de

    1079- Effet Mössbauer et techniques complémentaires : III. 2014 L'EXAFS appliqué aux déterminations synchrotron, l'EXAFS devient une technique de plus en plus utilisée pour l'étude de l'ordre local dans les système complexe, l'EXAFS peut donner l'ordre local autour de chacun des constituants. Cependant, l

  20. Frottement interne dans le zirconium irradie aux neutrons A 77 K

    Microsoft Academic Search

    R. Pichon; E. Bisognis; P. Mosek

    1973-01-01

    Le zirconium présente après irradiation neutronique à 77 K sept pics de frottement interne. Les deux premiers correspondent à la réorientation complexe de ?interstitiel libre migrant à trois dimensions en fin de stade I. Le dipole élastique créé par cet interstitiel est monoclinique et sa réorientation complexe donne lieu à un pic dissocié conforme aux prévisions de Nowick. Ce défaut

  1. La privatisation en Pologne : d'une approche plurielle aux difficultés de la privatisation de masse

    Microsoft Academic Search

    Jean-François Nivet

    1994-01-01

    [fre] La privatisation en Pologne : d'une approche plurielle aux difficultés de la privatisation de masse . La part du secteur privé dans le PIB polonais a franchi depuis 1 993 le seuil des 50 %. Cette progression provient en premier lieu du dynamisme de l'initiative privée qui s'est manifestée par la création ex nihilo de nouvelles entreprises. Le succès

  2. La dama boba de Lope de Vega adapte aux enfants Florence RAYNI

    E-print Network

    Paris-Sud XI, Université de

    1 « La dama boba de Lope de Vega adaptée aux enfants » Florence RAYNIÉ Université de Toulouse II-Le Mirail La dama boba, l'une des comedias les plus connues et les plus représentées de Lope de Vega a été Vega. Cette adaptation, publiée dans la collection Araluce Las obras maestras al alcance de los niños

  3. L'ethnologue face aux racismes : l'exemple tsigane** Patrick Williams*

    E-print Network

    Paris-Sud XI, Université de

    L'ethnologue face aux racismes : l'exemple tsigane** Patrick Williams* Ayant fait depuis des majoritaire. The ethnologist and racisms : the example of gipsies Victims of exclusion for centuries, gipsy française, 1988/2 (Ethnologie et racismes, ss la dir. Jacques Gutwirth et Jean-Claude Schmitt), pp. 173

  4. Coring Performance to Characterise the Geology in the ``Cran aux Iguanodons'' of Bernissart (Belgium)

    Microsoft Academic Search

    Jean-Pierre Tshibangu; Fabrice Dagrain; Hughes Legrain; Benoît Deschamps

    2004-01-01

    The Cran aux iguanodons of Bernissart is a sinkhole (or chimney caving) with a valuable paleontological deposit due to the exceptional quantity and diversity of fossils found during the excavation conducted from 1878 to 1881. In fact, bones have been discovered in a clayey geological formation when digging à mine gallery at the -322 m level. A subsequent extraction gave

  5. DPARTEMENT DE PHYSIQUE Politique de financement des tudiants aux cycles suprieurs,

    E-print Network

    Parrott, Lael

    DÉPARTEMENT DE PHYSIQUE Politique de financement des étudiants aux cycles supérieurs, adoptée par l étudiants et étudiantes des cycles supérieurs du département de physique; toute dérogation nécessite une physique : bourses d'admission de 10 000 $ par année pour un an à la maîtrise (deux ans pour la maîtrise en

  6. Dpartement*de*physique**Universit*de*Montral* Plan*d'tudes*aux*cycles*suprieurs*

    E-print Network

    Parrott, Lael

    1" " Département*de*physique*­*Université*de*Montréal* Plan*d'études*aux*cycles*supérieurs* * L*d'étude* Maîtrise"en"physique" Avec"mémoire" Avec"stage" Doctorat"en"physique"" Régulier" Passage"et"durée":" ___________________________________________" Complément"du"directeur"de"recherche":" _________________________" Bourse"du"Département"de"physique

  7. Reflets de la Physique n414 Pour donner une meilleure visibilit aux femmes physiciennes,

    E-print Network

    van Tiggelen, Bart

    Reflets de la Physique n°414 Pour donner une meilleure visibilité aux femmes physiciennes, la Commission Femmes & Physique de la SFP a proposé à la rédaction de Reflets de la physique de publier un, puis vivement soutenue au CNRS par la Mission pour la place des femmes et par l'Institut de physique

  8. Dpartement d'informatique -Facult des sciences Activits offertes aux tudes suprieures

    E-print Network

    Spino, Claude

    Département d'informatique - Faculté des sciences Activités offertes aux études supérieures 2013-2014 AUTOMNE 2013 Sigle Titre Gr Prof(s) Horaire Local IFT703 Informatique cognitive 1-51 Pigot, Hélène LU 1430 2014 Sigle Titre Gr Prof(s) Horaire Local IFT821 Méthodologie de communication en informatique51 IGL821

  9. Objectifs de la formation Former des professionnels de l'informatique aux nouvelles

    E-print Network

    Chaine, Raphaëlle

    Objectifs de la formation Former des professionnels de l'informatique aux nouvelles technologies de'infrastructures ou consultant. Master Professionnel GE Informatique EN APPRENTISSA Conditions d'accès Être titulaire d'un Master 1ère année informatique ou de formation équivalente (Bac+4) Avoir moins de 26 ans

  10. Rencontres halieutiques -Rsum Session 1 -La pche et l'aquaculture face aux enjeux

    E-print Network

    Paris-Sud XI, Université de

    Rencontres halieutiques - Résumé Session 1 - La pêche et l'aquaculture face aux enjeux du écosystèmes (ESE), AGROCAMPUS OUEST Pêche et aquaculture : les enjeux environnementaux Le secteur des pêches et de l'aquaculture est aujourd'hui un secteur en pleine mutation. L'enjeu est de placer ces

  11. L'INDEPENDANCE DU COMMISSAIRE AUX COMPTES : UNE ANALYSE EMPIRIQUE BASEE

    E-print Network

    Boyer, Edmond

    de contrôle ­ Niveau de croyance dans un monde juste. Abstract Three psychological components of auditor behaviour confronted with an audit conflict situation have been studied. The most independent'indépendance correspond à la capacité de résistance de l'auditeur aux pressions des dirigeants de l'entreprise (Watts et

  12. CARACTRISTIQUES DES SOURCES A PLASMAS NCESSAIRES AUX PROCESSUS CHIMIQUES (*)

    E-print Network

    Paris-Sud XI, Université de

    , corona and glow discharges). The application of the sources to chemical engineering introduces two effet thermique (arc, torche) et source à excitation sélective (laser, décharge couronne...). Toutefois possible. Abstract. 2014 Plasma source studies have permitted classification of electrical discharges

  13. CIEAEM 57 Italie Italy Foire aux ides, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session

    E-print Network

    Spagnolo, Filippo

    CIEAEM 57 ­ Italie ­ Italy Foire aux idées, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session July 23-29, 2005, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session July 23-29, 2005

  14. CIEAEM 57 Italie Italy Foire aux ides, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session

    E-print Network

    Spagnolo, Filippo

    CIEAEM 57 ­ Italie ­ Italy Foire aux idées, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session July 23-29, 2005. The contribution will be organised as a poster and will present illustrations of the way student teachers meet

  15. CIEAEM 57 Italie Italy Foire aux ides, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session

    E-print Network

    Spagnolo, Filippo

    CIEAEM 57 ­ Italie ­ Italy Foire aux idées, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session July 23-29, 2005 with his education. In this poster, we study the students' personal school-routes as a variable

  16. CENTRE DE RADAPATION LUCIE-BRUNEAU Le Centre de radaptation Lucie-Bruneau offre aux personnes ayant une dficience

    E-print Network

    Parrott, Lael

    neuropsychologue évalue les fonctions cognitives de la clientèle, puisque pour s'adapter, il faut intégrer de'interventions de nature cognitive et en faisant équipe avec l'usager qui est souvent aux prises avec des troubles

  17. A combinatorial TIR1/AFB-Aux/IAA co-receptor system for differential sensing of auxin.

    PubMed

    Calderón Villalobos, Luz Irina A; Lee, Sarah; De Oliveira, Cesar; Ivetac, Anthony; Brandt, Wolfgang; Armitage, Lynne; Sheard, Laura B; Tan, Xu; Parry, Geraint; Mao, Haibin; Zheng, Ning; Napier, Richard; Kepinski, Stefan; Estelle, Mark

    2012-05-01

    The plant hormone auxin regulates virtually every aspect of plant growth and development. Auxin acts by binding the F-box protein transport inhibitor response 1 (TIR1) and promotes the degradation of the AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) transcriptional repressors. Here we show that efficient auxin binding requires assembly of an auxin co-receptor complex consisting of TIR1 and an Aux/IAA protein. Heterologous experiments in yeast and quantitative IAA binding assays using purified proteins showed that different combinations of TIR1 and Aux/IAA proteins form co-receptor complexes with a wide range of auxin-binding affinities. Auxin affinity seems to be largely determined by the Aux/IAA. As there are 6 TIR1/AUXIN SIGNALING F-BOX proteins (AFBs) and 29 Aux/IAA proteins in Arabidopsis thaliana, combinatorial interactions may result in many co-receptors with distinct auxin-sensing properties. We also demonstrate that the AFB5-Aux/IAA co-receptor selectively binds the auxinic herbicide picloram. This co-receptor system broadens the effective concentration range of the hormone and may contribute to the complexity of auxin response. PMID:22466420

  18. MISB40Y -Series chronologiques Feuille d'exercices n1 : Introduction aux series chronologiques

    E-print Network

    Lagnoux, Agnès

    M1 ISMAG MISB40Y - S´eries chronologiques Feuille d'exercices n°1 : Introduction aux s´eries´ethodes. 2 #12;M1 ISMAG MISB40Y - S´eries chronologiques Feuille d'exercices n°2 : Moyennes mobiles et d chronologique (avec p´eriodes superpos´ees puis avec p´eriodes successives). Commenter. 2. Calculer la s´erie

  19. Synthesis, self-assembly, and magnetic properties of [FePt]1-xAux nanoparticles

    Microsoft Academic Search

    Shishou Kang; Zhiyong Jia; David E. Nikles; J. W. Harrell

    2003-01-01

    [FePt]1-xAux nanoparticles were prepared by the simultaneous polyol reduction of platinum acetylacetonate and gold acetate and the thermal decomposition of iron pentacarbonyl, giving 3.5-nm-diameter FePt particles with gold atoms substituted in the lattices. The addition of gold promoted the face-centered cubic to tetragonal phase transition, thereby reducing the temperature required for this transition by more than 150°C compared with FePt

  20. Actualit scientifiqueActualit scientifique L'ADN : de la biologie aux

    E-print Network

    Ingrand, François

    Actualité scientifiqueActualité scientifique L'ADN : de la biologie aux technologies, un nouveau efforts pour séquencer l'ADN à travers un nanopore ou, plus récemment, par manipulation mécanique. Si l ont permis de mettre au point une filière industrielle de synthèse d'ADN,des méthodes de modifi

  1. Auxin-responsive grape Aux/IAA9 regulates transgenic Arabidopsis plant growth.

    PubMed

    Fujita, Keiko; Horiuchi, Haruka; Takato, Haruka; Kohno, Minako; Suzuki, Shunji

    2012-07-01

    We report the characterization of VvIAA9, an auxin/indole-3-acetic acid (Aux/IAA) protein, in grapevine (Vitis vinifera L.). VvIAA9 was expressed abundantly in leaves and berries. VvIAA9 transcription was drastically upregulated from anthesis to onset of ripening (termed véraison), in which berry diameter rapidly increased. Treatment with exogenous IAA induced VvIAA9 expression in grape leaves, suggesting that VvIAA9 is an auxin-responsive Aux/IAA protein. The overexpression of VvIAA9 in Arabidopsis thaliana promoted plant growth, including rapid floral transition. However, no morphological differences were observed between the control plant and the VvIAA9-overexpressing plant. The overexpression of VvIAA9 in Arabidopsis plants rendered the plants hyposensitive to exogenous IAA. The exogenous IAA treatment did not induce VvIAA9-overexpressing Arabidopsis plant growth and expression of IAA-responsive HAT2. Taken together, we conclude that grape Aux/IAA9 protein is likely to play a crucial role as a plant growth regulator. PMID:22535320

  2. Approche aux soins en milieu communautaire à des adultes ayant une déficience développementale

    PubMed Central

    Osmun, W.E.; Chan, Nelson; Solomon, Robert

    2015-01-01

    Résumé Objectif Passer en revue les obligations d’ordre médical, éthique et juridique dans les soins aux adultes ayant une déficience développementale (DD) qui vivent dans la communauté. Sources des données Des recherches ont été faites dans Google et MEDLINE à l’aide des mots disabled, disability, vulnerable et community. Les lois pertinentes ont fait l’objet d’un examen. Message principal Le traitement d’un patient ayant une DD varie en fonction de facteurs comme la pathogenèse du problème actuel du patient, ses affections concomitantes, la gravité de ses déficiences et ses soutiens sociaux habituels. Bien que l’on s’entende sur les bienfaits du transfert des soins institutionnels vers des soins communautaires pour les patients ayant une DD, il s’est révélé difficile de leur dispenser des soins de grande qualité en milieu communautaire. Par ailleurs, il existe peu de travaux de recherche sur les façons d’offrir efficacement des soins aux adultes ayant une DD. En tant que professionnels des soins primaires, les médecins de famille sont souvent le premier point de contact pour les patients et sont à la fois responsables de la coordination et de la continuité des soins. Compte tenu de l’importance accrue accordée aux soins préventifs et à la détection précoce des maladies, la participation active du patient revêt aussi une grande importance. Les valeurs et les objectifs du patient sont des éléments essentiels à prendre en compte, même s’ils vont à l’encontre de la bonne santé du patient ou des propres valeurs du clinicien. Les lois s’appliquant aux personnes vulnérables varient d’une province à l’autre. Par conséquent, l’obligation de signaler des mauvais traitements suspectés pourrait différer selon que la personne vulnérable habite dans un centre de soins ou la communauté, que la personne qui soupçonne le comportement abusif est un fournisseur de services ou un professionnel de la santé ou encore que les circonstances spécifiques répondent à la définition légale de mauvais traitement ou de négligence. Conclusion Les professionnels des soins primaires doivent dispenser aux adultes ayant une DD des soins empreints de compassion qui respectent les souhaits du patient.

  3. The Morne Aux Diables volcano, Dominica, Lesser Antilles: A stratigraphic and petrologic study.

    NASA Astrophysics Data System (ADS)

    Daly, G. L.; Smith, A. L.; Rheubottom, A. N.; Fryxell, J. E.

    2008-12-01

    Morne Aux Diables is a topographically distinct stratovolcano located at the northernmost end of the island of Dominica, Lesser Antilles. In 2007, observations were conducted, and over 3,000 digital photographs were taken, of the well-exposed sea cliffs around Dominica. These observations, together with photogeological analysis of approximately 500 of these digital photographs of sea cliffs around the northern part of Dominica, have significantly improved our understanding of the geology of Morne aux Diables volcano, which previously had been based on scattered land exposures. The photographs were used to identify genetic packages of strata related to volcanogenic events and trace them around large sectors of the volcano's flanks. Based on these new studies, together with previous data, Morne aux Diables appears to have undergone two periods of activity, an older period dated between 2.1-1.5 Ma and a younger period dated at around 50,000 years B.P. Deposits associated with the older cone-forming activity are primarily composed of block and ash flows and surges associated with Pelean-style activity. These can be subdivided into a number of sequences based on the presence of paleosols. Domes associated with these eruptions are found both in the central vent area as well as around the flanks of the volcano. The upper deposits in the sea cliffs on the eastern, northern and western flanks are a thick sequence of surges that have been provisionally correlated with a well-exposed sequence of semi-vesicular block and ash flows and surge deposits at Morne a Louis on the west coast. The presence of these surge deposits at the top of the sea cliffs suggests that the older period of activity ended with open-crater Asama-style eruptions. Following an extensive quiescent period, renewed Pelean-style activity produced valley-fill block and ash flow and surge deposits, exposed on both the eastern and western sides of the volcano, together with associated domes (both central and parasitic). Petrographic studies show that Morne Aux Diables volcano is composed of andesites and dacites with a mineral assemblage of plagioclase+augite±hypersthene with minor hornblende and quartz. Geochemically both the older and younger volcanic rocks show trends, especially in terms of alkalis, that are slightly lower and cross- cut from those shown by the other centers on Dominica. These stratigraphic and petrologic studies will help further elucidate the volcanic history of Morne aux Diables and allow a petrologic-stratigraphic model of its formation.

  4. Méthode de calcul des antennes linéaires symétriques. applications au doublet, au doublet replié, a l’Antenne Yagi

    Microsoft Academic Search

    Louis Guillou; Jean-Pierre Daniel; Gérard Dubost

    1974-01-01

    \\u000a Résumé  Une étude théorique sur le doublet a amené les auteurs à élaborer une méthode numérique spécifique aux éléments rayonnants\\u000a linéaires symétriques. Des confrontations avec l’expérience sur les cas bien connus du doublet de longueur moyenne et du doublet\\u000a replié sont suivies d’une application aux antennes de type « Yagi ».

  5. Principe d'alimentation par convertisseurs multiniveaux à stockage intégré - Application aux accélérateurs de particules

    Microsoft Academic Search

    Claude Fahrni; A Rufer

    2008-01-01

    Facilities operating in cycles, such as particles accelerators, require pulsed power. Directly drawing this pulsed power from the industrial network is generally not acceptable. A system with a local energy storage system lessens the impact on the network. In this work, a power supply is proposed that allows pulsed operation of a proton synchrotron without disturbing the industrial network with

  6. Modèles animaux d’allergie alimentaire. Application aux protéines de blé

    Microsoft Academic Search

    M. Bodinier; M. Leroy; K. Adel-Patient

    2008-01-01

    The allergens responsible for wheat food allergy are beginning to be characterized. Nevertheless, animal models that produce highly-specific IgE and clinical symptoms comparable to those observed in allergic patients are of great interest for precise studies of allergens and of the mechanisms involved in wheat allergy. The aim of our research was to develop, in the first instance, a mouse

  7. INSTRUMENTATION DE L'UTILISATION D'UN OUTIL METHODOLOGIQUE : APPLICATION AUX 9 ECRANS DE LA

    E-print Network

    Paris-Sud XI, Université de

    METHODE TRIZ. Thierry Chambon, Denis Choulier, Alain-Jérôme Fougères, Pierre-Alain Weite Laboratoire M3M réflexion et d'instrumentation de la démarche «9 écrans» de TRIZ, qui propose de questionner l méthodologique TRIZ, 9 écrans, scénarisation, activité réflexive. 1 Introduction : 9 écrans, quoi et pourquoi Le

  8. La théorie de la sous-alimentation en lubrification elastohydrodynamique: application aux graisses et emulsions

    NASA Astrophysics Data System (ADS)

    Lubrecht, Ton; Mazuyer, Denis; Cann, Philippa

    2001-07-01

    In classical fluid lubrication the film thickness is mainly determined by entrainment velocity and oil viscosity. At high pressure, elastic deformation occurs changing the local geometry: this is the elastohydrodynamic lubrication regime (EHL). When a limited amount of lubricant is available to the contact, a component failure due to lubricant starvation can result. A new starvation model is presented, using the amount of oil on the surfaces as the key parameter controlling starvation. It is successfully applied to describe the contacts lubricated with multi-phase fluids such as emulsions and greases, which combine starvation with a very complex rheology.

  9. Vers une méthode de réglage expérimentale des commandes PID floues : application aux systèmes électromécaniques

    NASA Astrophysics Data System (ADS)

    Maussion, P.; Hissel, D.

    1998-08-01

    Electrical and electromechanical systems have to satisfy to more and more constrained specifications. Therefore, non-linear control structures must be spread out. Among them, fuzzy logic control can be one interessant and performant alternative. The main handicap of this kind of stucture resides in the fact that the tuning parameters are very numerous. In this paper, we first propose an on-site tuning strategy of this set of parameters in the case of a fuzzy proportionnal-integrative controller based on the experimental designs methodology and on a limited number of pre-defined closed-loop experiments. Then, a complete set of predetermined parameters for a fuzzy proportionnal-integrative-derivative controller will be given. These parameters have been optimized on a specified benchmark according to an IAE criterion. They are calculated like the Ziegler-Nichols or Broïda methodology on conventional controllers; that is, using a single open-loop step response to obtain a model of a first-order plus delay transfert function. Validity limits for this method are provided. Les systèmes électriques ou électromécaniques doivent satisfaire à des spécifications de plus en plus contraignantes qui nécessitent la mise au point de structures de commande non linéaires. Parmi celles-ci, la commande par logique floue constitue une alternative intéressante et performante. Son principal handicap réside dans le nombre très important de paramètres à régler. Dans cet article, nous nous proposons de systématiser ces réglages dans deux cas de figure. Tout d'abord nous utiliserons la méthodologie des plans d'expérimentations pour effectuer un réglage sur site d'un contrôleur flou de type proportionnel-intégral. Ce réglage sera obtenu en ne réalisant qu'un nombre limité d'essais expérimentaux en boucle fermée avec des combinaisons prédéfinies des paramètres à régler. La combinaison optimale de ces paramètres au sens d'un critère de type IAE (Intégrale de la valeur Absolue de l'Erreur) sera déduite de l'exploitation des résultats des essais. Dans un deuxième temps, nous proposerons des réglages prédéfinis et optimisés (au sens du même critère) d'un contrôleur flou de type proportionnel-intégral-dérivé. Ces réglages préétablis ne nécessiteront qu'un seul essai d'identification du système à contrôler en boucle ouverte et peuvent donc se rapprocher des méthodologies classiques et éprouvées de réglage sur site que constituent les réglages de Ziegler-Nichols ou de Broïda pour des contrôleurs conventionnels. Dans cet article, les jeux de paramètres préétablis que nous fournirons seront valables pour des systèmes dont la réponse indicielle en boucle ouverte est modélisable sous la forme d'une fonction de transfert du premier ordre plus un retard pur. Les limites de validité de cette méthode seront précisées.

  10. Morne aux Diables. a potentially active volcano in northern Dominica, Lesser Antilles

    NASA Astrophysics Data System (ADS)

    Rheubottom, A. N.; Smith, A. L.; Roobol, M. J.

    2005-12-01

    The island of Dominica, which is located near the center of the Lesser Antilles island arc, comprises at least 8 potentially active volcanoes. One of these is Morne aux Diables, an isolated composite cone situated at the extreme northern end of the island. Age dating suggests that the main cone building activity occurred between 1.5 and 1.0 million years ago. Exposed on the volcano's flanks however are a number of unconsolidated valley-fill block and ash flow deposits suggesting more recent activity. One of these deposits, on the north-east flank of the volcano, has been recently dated at > 46,000 years B.P. Other evidence of potential activity from this center includes the presence of warm (27°C), acidic (pH 1.6), sulfate-rich springs on the summit of the volcano, hot springs on the coast, and the occurrence in 2002 and 2003 of shallow earthquake swarms partially located beneath the volcano. Morne aux Diables is dominantly composed of deposits of block and ash flows and associated domes from Pelean-style activity, however, semi-vesicular andesite block and ash flows and surges (Asama-style activity) and pumiceous lapilli falls (Plinian-style activity) are locally abundant. The Pelean domes are located both in the summit region and along the southern flanks of the volcano. Petrologically, the volcano is composed of a monotonous series of porphyritic andesites and dacites containing phenocrysts of plagioclase+augite-hypersthene with very sparse crystals of hornblende and quartz. Petrological models suggest the Morne aux Diables andesites and dacites can be produced by fractional crystallization of basaltic magma (such as those erupted from centers such as Morne Anglais and Morne Plat Pays in the south). Minor variations within this suite of andesites and dacites can be related to upper crustal fractionation of phenocryst phases.

  11. Genome-Wide Identification and Expression Profiling Analysis of the Aux/IAA Gene Family in Medicago truncatula during the Early Phase of Sinorhizobium meliloti Infection

    PubMed Central

    Zhang, Lei; Sun, Tao; Xu, Luqin; Tie, Shuanggui; Wang, Huizhong

    2014-01-01

    Background Auxin/indoleacetic acid (Aux/IAA) genes, coding a family of short-lived nuclear proteins, play key roles in wide variety of plant developmental processes, including root system regulation and responses to environmental stimulus. However, how they function in auxin signaling pathway and symbiosis with rhizobial in Medicago truncatula are largely unknown. The present study aims at gaining deeper insight on distinctive expression and function features of Aux/IAA family genes in Medicago truncatula during nodule formation. Principal Findings Using the latest updated draft of the full Medicago truncatula genome, a comprehensive identification and analysis of IAA genes were performed. The data indicated that MtIAA family genes are distributed in all the M. truncatula chromosomes except chromosome 6. Most of MtIAA genes are responsive to exogenous auxin and express in tissues-specific manner. To understand the biological functions of MtIAA genes involved in nodule formation, quantitative real-time polymerase chain reaction (qRT-PCR) was used to test the expression profiling of MtIAA genes during the early phase of Sinorhizobium meliloti (S. meliloti) infection. The expression patterns of most MtIAA genes were down-regulated in roots and up-regulated in shoots by S. meliloti infection. The differences in expression responses between roots and shoots caused by S. meliloti infection were alleviated by 1-NOA application. Conclusion The genome-wide identification, evolution and expression pattern analysis of MtIAA genes were performed in this study. The data helps us to understand the roles of MtIAA-mediated auxin signaling in nodule formation during the early phase of S. meliloti infection. PMID:25226164

  12. J. Gervais -Le corps des Ponts et Chausses aux prises avec le dbat public Dans : LE BIANIC Thomas et VION Antoine, Action publique et lgitimits

    E-print Network

    Paris-Sud XI, Université de

    J. Gervais - Le corps des Ponts et Chaussées aux prises avec le débat public 134 Dans : LE BIANIC société », 2008. Chapitre 10 Le corps des Ponts et Chaussées aux prises avec le débat public L'action publique de l'École nationale des Ponts et Chaussées, le 21/10/2004. Longtemps, l'appartenance au corps des

  13. Introduction Restriction aux ordres totaux Dveloppement algbrique Passage du 2D au 3D Caractrisation 3D Conclusion Dtermination du chirotope d'une base en fonction

    E-print Network

    Pocchiola, Michel

    Introduction Restriction aux ordres totaux Développement algébrique Passage du 2D au 3D Caractérisation 3D Conclusion Détermination du chirotope d'une base en fonction d'ordres sur les coordonnées de;Introduction Restriction aux ordres totaux Développement algébrique Passage du 2D au 3D Caractérisation 3D

  14. Diversity of Stability, Localization, Interaction and Control of Downstream Gene Activity in the Maize Aux/IAA Protein Family

    PubMed Central

    Ludwig, Yvonne; Berendzen, Kenneth W.; Xu, Changzheng; Piepho, Hans-Peter; Hochholdinger, Frank

    2014-01-01

    AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) proteins are central regulators of auxin signal transduction. They control many aspects of plant development, share a conserved domain structure and are localized in the nucleus. In the present study, five maize Aux/IAA proteins (ZmIAA2, ZmIAA11, ZmIAA15, ZmIAA20 and ZmIAA33) representing the evolutionary, phylogenetic and expression diversity of this gene family were characterized. Subcellular localization studies revealed that ZmIAA2, ZmIAA11 and ZmIAA15 are confined to the nucleus while ZmIAA20 and ZmIAA33 are localized in both the nucleus and the cytoplasm. Introduction of specific point mutations in the degron sequence (VGWPPV) of domain II by substituting the first proline by serine or the second proline by leucine stabilized the Aux/IAA proteins. While protein half-life times between ?11 min (ZmIAA2) to ?120 min (ZmIAA15) were observed in wild-type proteins, the mutated forms of all five proteins were almost as stable as GFP control proteins. Moreover, all five maize Aux/IAA proteins repressed downstream gene expression in luciferase assays to different degrees. In addition, bimolecular fluorescence complementation (BiFC) analyses demonstrated interaction of all five Aux/IAA proteins with RUM1 (ROOTLESS WITH UNDETECTABLE MERISTEM 1, ZmIAA10) while only ZmIAA15 and ZmIAA33 interacted with the RUM1 paralog RUL1 (RUM-LIKE 1, ZmIAA29). Moreover, ZmIAA11, ZmIAA15 ZmIAA33 displayed homotypic interaction. Hence, despite their conserved domain structure, maize Aux/IAA proteins display a significant variability in their molecular characteristics which is likely associated with the wide spectrum of their developmental functions. PMID:25203637

  15. Auxin-nonresponsive grape Aux/IAA19 is a positive regulator of plant growth.

    PubMed

    Kohno, Minako; Takato, Haruka; Horiuchi, Haruka; Fujita, Keiko; Suzuki, Shunji

    2012-02-01

    We report the characterization of VvIAA19, an auxin/indole-3-acetic acid (Aux/IAA) protein, in grapevine (Vitis vinifera L.). VvIAA19 was expressed abundantly in berries. VvIAA19 transcription was rapidly increased at pre-anthesis and then decreased during fruit set. Before véraison, however, VvIAA19 gene expression was upregulated again and maximum expression was maintained until the end of ripening. Exogenous IAA did not induce VvIAA19 expression in grape leaves, suggesting that VvIAA19 might be auxin-nonresponsive. The overexpression of VvIAA19 in Arabidopsis thaliana had a notable effect on plant growth. Although no morphological changes were observed, transgenic Arabidopsis plants overexpressing VvIAA19 exhibited faster growth, including root elongation and floral transition, than the control plant, suggesting that the constitutive expression of VvIAA19 protein resulted in increased growth rates without any detectable harm. Taken together, we conclude that grape Aux/IAA19 protein is likely to play a crucial role as a plant growth regulator. PMID:21562765

  16. Morphological variations in AuxSiy nanostructures under variable pressure and annealing conditions

    NASA Astrophysics Data System (ADS)

    Rath, A.; Dash, J. K.; Juluri, R. R.; Satyam, P. V.

    2015-03-01

    Well-ordered, substrate symmetry-driven, AuxSiy structures of average size ~25 nm were formed under ultra-high vacuum (UHV) conditions using molecular beam epitaxy method. Post-annealing was done at 500 °C in three different vacuum conditions: (1) low vacuum (LV) (10-2 mbar), (2) high vacuum (HV) (10-5 mbar) and (3) UHV (10-10 mbar) (MBE chamber). For both HV and LV cases, the AuxSiy nanostructures were found to have their corners rounded unlike in UHV case where the structures have sharp edges. In all the above three cases, samples were exposed to air before annealing. In situ annealing inside UHV chamber without exposing to air resulted in well-aligned rectangles with sharp corners, while sharp but irregular island structures were found for air exposed and UHV annealing system. The role of residual gases present in LV and HV annealing environment and inhibition of lateral surface diffusion due to the presence of surface oxide (through air exposure) would be discussed. Annealing at various conditions yielded variation in the coverage and correspondingly, the average area of nanostructures varied from a ~329 nm2 (as deposited) to ~2,578 nm2 (at high temperature). High-resolution transmission electron microscopy (planar and cross section) has been utilized to study the morphological variations.

  17. Identification de ligands des enzymes de rsistance aux aminoglycosides par RMN. NMR identification of ligands of aminoglycoside resistance enzymes.

    E-print Network

    Paris-Sud XI, Université de

    - 1 - Identification de ligands des enzymes de résistance aux aminoglycosides par RMN. NMR identification of ligands of aminoglycoside resistance enzymes. Frédérique Maurice1 , Guillaume Bégis2 , Laurent principalement la conséquence de l'action d'enzymes qui modifient chimiquement ces antibiotiques et les empêchent

  18. CIEAEM 57 Italie Italy Foire aux ides, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session

    E-print Network

    Spagnolo, Filippo

    CIEAEM 57 ­ Italie ­ Italy Foire aux idées, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session July 23-29, 2005 will have a format of a poster. It will focus on the illustrations of the above goals. Problems from

  19. CIEAEM 57 Italie Italy Foire aux ides, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session

    E-print Network

    Spagnolo, Filippo

    CIEAEM 57 ­ Italie ­ Italy Foire aux idées, Session de Poster Piazza Armerina, Forum of Ideas, Poster Session July 23-29, 2005. Kiliskiego 12, piotr@wlodkowic.pl The poster is to present the first results of research made among teachers

  20. Du suicide de Mme Follin en 1828 aux suicides du dbut du XXe sicle: pour une tude

    E-print Network

    Paris-Sud XI, Université de

    Du suicide de Mme Follin en 1828 aux suicides du début du XXe siècle: pour une étude des violences'extinction du suicide, Revue de Rouen, 1844). Introduction Le 16 décembre 1828 le préfet de la Seine « suicide » chez les aliénés « fous moraux » ou suicidaires. L'ouverture des cerveaux permettrait de définir

  1. CONTRIBUTION A L'TUDE DU DURCISSEMENT DU NIOBIUM ET DE CERTAINS DE SES ALLIAGES LIS AUX INTERSTITIELS,

    E-print Network

    Paris-Sud XI, Université de

    387 CONTRIBUTION A L'ÉTUDE DU DURCISSEMENT DU NIOBIUM ET DE CERTAINS DE SES ALLIAGES LIÉS AUX traction effectués sous vide entre 20 et 1 200 °C sur divers alliages de Niobium ont permis de distinguer. Abstract. 2014 Tensile tests were run on different Niobium alloys from 20 to 1 200 °C in high vacuum

  2. Etude du vieillissement de la glace Ih par mesures de frottement interne et par observation en topographie aux rayons X

    E-print Network

    Paris-Sud XI, Université de

    1473 Etude du vieillissement de la glace Ih par mesures de frottement interne et par observation en par mesures de frottement interne et par des observations en topographie aux rayons X. Ces mesures défauts de réseau. En effet, nos études antérieures [11, 14, 17] portant sur le frottement interne de la

  3. APPLICATION DE L'ANALYSE THERMIQUE DIFFRENTIELLE A L'TUDE DES VERRES

    E-print Network

    Paris-Sud XI, Université de

    647 APPLICATION DE L'ANALYSE THERMIQUE DIFFÉRENTIELLE A L'ÉTUDE DES VERRES M. PROD'HOMME C. N. R. S., Institut du Verre, 34, rue Michel-Ange, 75016 Paris, France Résumé. 2014 L'analyse thermique différentielle'application de cette méthode simple au verre s'est déve- loppée grâce aux travaux de Tool et ses collaborateurs

  4. Le système opioïde endogène et l’addiction aux drogues1

    PubMed Central

    Maldonado, Rafael

    2010-01-01

    Résumé L’addiction aux drogues est une maladie psychiatrique chronique qui conduit à d’importantes altérations adaptatives dans les circuits de récompense du cerveau. Plusieurs systèmes de neurotransmission sont impliqués dans ces modifications. Cependant, un des systèmes neurochimiques qui joue un rôle essentiel dans l’addiction est le système opioïde endogène. Les récepteurs opioïdes et les peptides opioïdes endogènes sont très largement présents dans les structures cérébrales qui contrôlent les phénomènes de récompense, en particulier le système mésolimbique. Ces récepteurs et peptides opioïdes participent d’une manière sélective à plusieurs aspects des processus addictifs induits par les opiacés, les cannabinoïdes, les psychostimulants, l’alcool et la nicotine. Cette revue rend compte de l’état actuel des connaissances sur la participation de chaque composante du système opioïde endogène dans les propriétés addictives des différentes drogues. PMID:20176158

  5. H:\\INST\\AUXBGT\\FY13UWM\\Kickoff Info\\Kickoff Packet\\1213 Aux Kickoff Agenda.doc University of Wisconsin Milwaukee

    E-print Network

    Saldin, Dilano

    \\Internal Aux Financing\\Fund 128 Proj Cash Bal_as of 9-23-11.xls *NOTE: Cash balances shown do not include Cash Bal_as of 9-23-11.xls #12;SCHEDULE 2 Projected Cash Balance - (In Thousands $) Funds 123, 128/7/2011 H:\\INST\\AUXBGT\\FY13UWM\\Internal Aux Financing\\Fund 128 Proj Cash Bal_as of 9-23-11.xls #12;SCHEDULE

  6. CONDUCTION THERMIQUE DES VERRES AUX BASSES TEMPRATURES A. J. LEADBETTER (*), A. P. JEAPES et C. G. WATERFIELD

    E-print Network

    Paris-Sud XI, Université de

    95 CONDUCTION THERMIQUE DES VERRES AUX BASSES TEMPÉRATURES A. J. LEADBETTER (*), A. P. JEAPES et C. 2014 Les conductions thermiques des verres GeO2, B2O3, BeF2, As2S3, As2Se3, GeS2, CaMgSi2O6, verre et phonons sur les frontières des cristallites. Tous les verres présentent un épaulement dans les courbes K

  7. The Tomato Aux/IAA Transcription Factor IAA9 Is Involved in Fruit Development and Leaf MorphogenesisW?

    PubMed Central

    Wang, Hua; Jones, Brian; Li, Zhengguo; Frasse, Pierre; Delalande, Corinne; Regad, Farid; Chaabouni, Salma; Latché, Alain; Pech, Jean-Claude; Bouzayen, Mondher

    2005-01-01

    Auxin/indole-3-acetic acid (Aux/IAA) proteins are transcriptional regulators that mediate many aspects of plant responses to auxin. While functions of most Aux/IAAs have been defined mainly by gain-of-function mutant alleles in Arabidopsis thaliana, phenotypes associated with loss-of-function mutations have been scarce and subtle. We report here that the downregulation of IAA9, a tomato (Solanum lycopersicum) gene from a distinct subfamily of Aux/IAA genes, results in a pleiotropic phenotype, consistent with its ubiquitous expression pattern. IAA9-inhibited lines have simple leaves instead of wild-type compound leaves, and fruit development is triggered before fertilization, giving rise to parthenocarpy. This indicates that IAA9 is a key mediator of leaf morphogenesis and fruit set. In addition, antisense plants displayed auxin-related growth alterations, including enhanced hypocotyl/stem elongation, increased leaf vascularization, and reduced apical dominance. Auxin dose–response assays revealed that IAA9 downregulated lines were hypersensitive to auxin, although the only early auxin-responsive gene that was found to be upregulated in the antisense lines was IAA3. The activity of the IAA3 promoter was stimulated in the IAA9 antisense genetic background, indicating that IAA9 acts in planta as a transcriptional repressor of auxin signaling. While no mutation in any member of subfamily IV has been reported to date, the phenotypes associated with the downregulation of IAA9 reveal distinct and novel roles for members of the Aux/IAA gene family. PMID:16126837

  8. Niveau socioéconomique et processus du recours aux soins par les familles de patients souffrant de troubles psychiques au Burkina Faso

    PubMed Central

    Yaogo, Ahmed; Sommer, Alain; Moulaï, Pierre; Chebili, Saïd; Abaoub-Germain, Agnès

    2014-01-01

    Introduction Le Burkina Faso a connu une amélioration constante depuis deux décennies de l'offre de soins en psychiatrie. De même, le taux d'alphabétisation sans cesse croissant s'accompagne d'une profonde modification des conceptions et des comportements. La présente étude visait à déterminer l?impact des déterminants socioéconomiques sur le processus du recours aux soins par les familles. Méthodes Il s'est agi d'une enquête transversale portant sur 200 familles, menée dans le service de psychiatrie du Centre Hospitalier Universitaire Yalgado Ouédraogo de Ouagadougou. Variable à expliquer: premier recours aux soins par les familles (guérisseur traditionnel ou prières religieuses vs. consultations psychiatrique ou médicale). Variable explicative: catégorie socioprofessionnelle classée en suivant la nomenclature des professions et catégories socioprofessionnelles; niveau d’études. L'analyse statistique a été effectuée à l'aide du logiciel SAS version 9.2. Le test du Khi deux a été utilisé. Résultats Il existait une association entre le choix du premier recours et la Profession et la catégorie socioprofessionnelledu « décideur » (p = 0.0006) ainsi que leniveau d’études du « décideur » (p = 0.0001). Conclusion La Profession et Catégorie Sociale et le niveau d'instruction scolaire pourraient être un marqueur important dans les politiques visant à optimiser les processus de recours aux soins des patients dans le circuit de soins. PMID:25161751

  9. Xe{sup +} formation following photolysis of Au-Xe: A velocity map imaging study

    SciTech Connect

    Hopkins, W. Scott; Woodham, Alex P.; Mackenzie, Stuart R. [Department of Chemistry, University of Oxford, Physical and Theoretical Chemistry Laboratory, South Parks Road, Oxford OX1 3QZ (United Kingdom); Plowright, Richard J.; Wright, Timothy G. [School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom)

    2011-03-07

    The photodissociation dynamics of Au-Xe leading to Xe{sup +} formation via the {Xi}{sub 1/2}-X{sup 2}{Sigma}{sup +} (v{sup '}, 0) band system (41 500-41 800 cm{sup -1}) have been investigated by velocity map imaging. Five product channels have been indentified, which can be assigned to photoinduced charge transfer followed by photodissociation in either the neutral or the [Au-Xe]{sup +} species. For the neutral species, charge transfer occurs via a superexcited Rydberg state prior to dissociative ionization, while single-photon excitation of the gold atom in Au{sup +}-Xe accesses an (Au{sup +})*-Xe excited state that couples to a dissociative continuum in Au-Xe{sup +}. Mechanisms by which charge transfer occurs are proposed, and branching ratios for Xe{sup +} formation via the superexcited Rydberg state are reported. The bond dissociation energy for the first excited state of Au{sup +}-Xe is determined to be {approx}9720 {+-} 110 cm{sup -1}.

  10. Electrofiltration: An Energy Efficient Alternative in Solid-Liquid Separations 

    E-print Network

    Bollinger, J. M.; Adams, R. A.

    1984-01-01

    unit opera tion in ultrafine particle dewatering. The Dorr-Oliver Electrofilter combines vacuum cake filtration with electro phoresis and electroosmosis. This results in an order of magnitude drop in energy use when compared to traditional dewater... of solids content and particle size. As particle size falls below ten microns, conventional mechanical dewatering such as vacuum filtration or centrifugation is limited in its water removal capability. The alter natives are: (1) flocculation...

  11. Adsorption of nanoparticles at the solid-liquid interface.

    PubMed

    Brenner, Thorsten; Paulus, Michael; Schroer, Martin A; Tiemeyer, Sebastian; Sternemann, Christian; Möller, Johannes; Tolan, Metin; Degen, Patrick; Rehage, Heinz

    2012-05-15

    The adsorption of differently charged nanoparticles at liquid-solid interfaces was investigated by in situ X-ray reflectivity measurements. The layer formation of positively charged maghemite (?-Fe(2)O(3)) nanoparticles at the aqueous solution-SiO(2) interface was observed while negatively charged gold nanoparticles show no adsorption at this interface. Thus, the electrostatic interaction between the particles and the charged surface was determined as the driving force for the adsorption process. The data analysis shows that a logarithmic particle size distribution describes the density profile of the thin adsorbed maghemite layer. The size distribution in the nanoparticle solution determined by small angle X-ray scattering shows an average particle size which is similar to that found for the adsorbed film. The formed magehemite film exhibits a rather high stability. PMID:22386203

  12. Intermetallic phase formation in thin solid-liquid diffusion couples

    Microsoft Academic Search

    F. Bartels; J. W. Jr. Morris; G. Dalke; W. Gust

    1994-01-01

    Conducting joints with low fabrication temperatures and high thermal stability are useful in modern electronics. This paper\\u000a discusses the potential use of intermetallic phases in making such joints. Thin interconnection layers that consist entirely\\u000a of intermetallic phases have been produced by joining planar Cu substrates that are coated with thin films of Sn. Thin layers\\u000a (1-5 m) of intermetallic phase

  13. Supersonic air flow due to solid-liquid impact.

    PubMed

    Gekle, Stephan; Peters, Ivo R; Gordillo, José Manuel; van der Meer, Devaraj; Lohse, Detlef

    2010-01-15

    A solid object impacting on liquid creates a liquid jet due to the collapse of the impact cavity. Using visualization experiments with smoke particles and multiscale simulations, we show that in addition, a high-speed air jet is pushed out of the cavity. Despite an impact velocity of only 1 m/s, this air jet attains supersonic speeds already when the cavity is slightly larger than 1 mm in diameter. The structure of the air flow closely resembles that of compressible flow through a nozzle-with the key difference that here the "nozzle" is a liquid cavity shrinking rapidly in time. PMID:20366598

  14. Continuous or catastrophic solid-liquid transition in jammed systems

    NASA Astrophysics Data System (ADS)

    Coussot, P.; Roussel, N.; Jarny, S.; Chanson, H.

    2005-01-01

    Pasty materials encountered in industry and in earth science are intermediate between solids and liquids either in terms of their internal structure (disordered but jammed) or from a mechanical point of view. Our results indicate that the apparent behavior of a particulate system (soils, suspensions, clays, etc.) can range from liquid-like to soil or solid-like depending on the relative importance of the energy supplied to it and its "state of jamming" which evolves in time, and the transition from one state to another may appear either continuous or catastrophic.

  15. Expression of wild-type PtrIAA14.1, a poplar Aux/IAA gene causes morphological changes in Arabidopsis

    PubMed Central

    Liu, Shanda; Hu, Qingnan; Luo, Sha; Li, Qianqian; Yang, Xiyu; Wang, Xianling; Wang, Shucai

    2015-01-01

    Aux/IAA proteins are transcriptional repressors that control auxin signaling by interacting with auxin response factors (ARFs). So far all of the identified Aux/IAA mutants with auxin-related phenotypes in Arabidopsis and rice (Oryza sativa) are dominant gain-of-function mutants, with mutations in Domain II that affected stability of the corresponding Aux/IAA proteins. On the other hand, morphological changes were observed in knock-down mutants of Aux/IAA genes in tomato (Solanum lycopersicum), suggesting that functions of Aux/IAA proteins may be specific for certain plant species. We report here the characterization of PtrIAA14.1, a poplar (Populus trichocarpa) homolog of IAA7. Bioinformatics analysis showed that PtrIAA14.1 is a classic Aux/IAA protein. It contains four conserved domains with the repressor motif in Domain I, the degron in Domain II, and the conserved amino acid signatures for protein–protein interactions in Domain III and Domain IV. Protoplast transfection assays showed that PtrIAA14.1 is localized in nucleus. It is unable in the presence of auxin, and it represses auxin response reporter gene expression. Expression of wild-type PtrIAA14.1 in Arabidopsis resulted in auxin-related phenotypes including down-curling leaves, semi-draft with increased number of branches, and greatly reduced fertility, but expression of the Arabidopsis Aux/IAA genes tested remain largely unchanged in the transgenic plants. Protein–protein interaction assays in yeast and protoplasts showed that PtrIAA14.1 interacted with ARF5, but not other ARFs. Consistent with this observation, vascular patterning was altered in the transgenic plants, and the expression of AtHB8 (Arabidopsis thaliana homeobox gene 8) was reduced in transgenic plants. PMID:26082787

  16. Intro Architectures HTML/xHTML CSS Formulaires PHP MVC JavaScript Securite Applications interactives

    E-print Network

    Ligozat, Anne-Laure

    Intro Architectures HTML/xHTML CSS Formulaires PHP MVC JavaScript S´ecurit´e Applications cours de Mireille Jouve 1 / 125 #12;Intro Architectures HTML/xHTML CSS Formulaires PHP MVC JavaScript S Formulaires PHP MVC JavaScript S´ecurit´e Objectifs Pourquoi ce cours ? Objectifs th´eoriques introduction aux

  17. L'EXPERIENCE DE LA ROUMANIE DANS L'APPLICATION DES NORMES IAS/IFRS

    E-print Network

    Paris-Sud XI, Université de

    L'EXPERIENCE DE LA ROUMANIE DANS L'APPLICATION DES NORMES IAS/IFRS Mihai RISTEA, professeur transition aux normes IAS/IFRS est une construction technique complexe qui suppose des ressources consacré à l'analyse de la manière dans laquelle s'est réalisée la mise en oeuvre des normes IAS/IFRS en

  18. Statut phospho-calcique en hémodialyse chronique dans l’Oriental Marocain: évaluation de l’adhésion aux recommandations K/DOQI et KDIGO

    PubMed Central

    Benabdellah, Nawal; Karimi, Ilham; Bentata, Yassamine; Yacoubi, Hicham; Haddiya, Intissar

    2013-01-01

    Les troubles phosphocalciques sont fréquents en hémodialyse chronique. Leurs conséquences justifient une prévention et un traitement adaptés aux recommandations des sociétés savantes. L’objectif de notre étude était de déterminer le statut phosphocalcique de nos patients hémodialysés chroniques (HDC) et l’évaluation des taux de conformité des indicateurs aux recommandations K/DOQI et KDIGO. Ainsi, nous avons réalisé une étude transversale incluant les 83 patients HDC du centre d’hémodialyse de l’hôpital Al Farabi d’Oujda. L’âge moyen de nos patients était de 49.8± 15.6 ans. Une prédominance masculine a été notée. La conformité des indicateurs du bilan phosphocalcique chez nos patients hémodialysés chroniques par rapport aux recommandations KDIGO était de l’ordre de 21.6%. Le pourcentage des patients ayant des données phosphocalciques conformes aux cibles recommandées par les K/DOQI était Les patients répondants simultanément aux quatres critères recommandés par les K/DOQI n’étaient que 8.4%. PMID:24570784

  19. Waste Heat Boilers for Incineration Applications 

    E-print Network

    Ganapathy, V.

    1998-01-01

    Incineration is a widely used process for disposing of solid, liquid and gaseous wastes generated in various types of industries. In addition to destroying pollutants, energy may also be recovered from the waste gas streams in the form of steam...

  20. Evolution de la résistance aux antibiotiques des entérobactéries isolées à l'Hôpital Général de Douala de 2005 à 2012

    PubMed Central

    Ebongue, Cécile Okalla; Tsiazok, Martial Dongmo; Mefo'o, Jean Pierre Nda; Ngaba, Guy Pascal; Beyiha, Gérard; Adiogo, Dieudonné

    2015-01-01

    Introduction Cette étude vise à déterminer le profil de résistance aux antibiotiques des entérobactéries isolées à l'Hôpital Général de Douala (Cameroun) et analyser leur évolution dans le temps. Méthodes Etude rétrospective, sur une période de huit ans (2005 - 2012), portant sur l'ensemble des souches d'entérobactéries isolées chez les malades ambulatoires et hospitalisés. Les prélèvements ont été analysés au laboratoire de bactériologie de l'Hôpital Général de Douala. Résultats Les entérobactéries étaient les germes les plus fréquents sur l'ensemble des souches isolées. Nous avons noté une prédominance d’Escherichia coli (48,5%) et de Klebsiella pneumoniae (32,8%). Pendant la période d’étude, nous avons observé des taux de résistance élevés aux principales classes d'antibiotiques, et une augmentation entre 2005 et 2012 de 29,1% à 51,6% pour les céphalosporines de troisième génération, de 29,2% à 44% pour la ciprofloxacine. L'imipénème, l'amikacine et la fosfomycine étaient les molécules les plus actives avec respectivement 1,3%, 12,9% et 13,4% des souches d'entérobactéries résistantes. Conclusion L’évolution des résistances des entérobactéries aux antibiotiques est un phénomène réel dans la ville de Douala. Il expose à des difficultés de prise en charge thérapeutique des infections. Lamaitrise actuelle de ce phénomène est une véritable urgence et nécessite une implication des pouvoirs publics. Des tests spécifiques de recherche des bétalactamases à spectre élargi (BLSE) et AmpC doivent être mis en place dans nos laboratoires afin de mettre en évidence les différents phénotypes de résistances.

  1. Universite Pierre et Marie Curie, Master de Mathematiques, M1, Equations aux derivees partielles MM046, 5 juin 2013

    E-print Network

    Lerner, Nicolas

    Universit´e Pierre et Marie Curie, Master de Math´ematiques, M1, Equations aux d - c x2 x = x1 x x1 + x2 x x2 = x1 + x2 et par cons´equent c = 2 x2 1 + 2 x2 2 - 2 2 x1x2 - 2 x2) = 1 - |x|, x R. La m´ethode des caract´eristiques donne x = u u = u x = x0 + u0(et - 1) u = u0et et

  2. Paternité des articles et intérêts concurrents : une analyse des recommandations aux auteurs des journaux traitant de pratique pharmaceutique

    PubMed Central

    Courbon, Ève; Tanguay, Cynthia; Lebel, Denis; Bussières, Jean-François

    2014-01-01

    RÉSUMÉ Contexte : La présence d’auteurs honorifiques et fantômes ainsi que les intérêts concurrents représentent des difficultés bien documentées, liées à la publication d’articles scientifiques. Il existe des lignes directrices encadrant la rédaction et la publication de manuscrits scientifiques, notamment celles de l’International Committee of Medical Journal Editors (ICMJE). Objectifs : L’objectif principal de cette étude descriptive et transversale visait à recenser les instructions portant sur la paternité des articles et les intérêts concurrents provenant des recommandations aux auteurs des journaux traitant de pratique pharmaceutique. L’objectif secondaire visait à déterminer des mesures correctrices pour une paternité des articles plus transparente. Méthode : La recherche a débuté par l’identification des journaux traitant de pratique pharmaceutique. La consultation des instructions aux auteurs des journaux a permis ensuite de recenser les recommandations destinées à éviter les problèmes de paternité des articles et d’intérêts concurrents. Finalement, les membres de l’équipe de recherche se sont consultés afin de définir des mesures correctrices possibles à l’intention des chercheurs. Résultats : Des 232 journaux traitant de pharmacie, 33 ont été définis comme traitant de pratique pharmaceutique. Un total de 24 (73 %) journaux mentionnaient suivre la politique de l’ICMJE, 14 (42 %) demandaient aux auteurs de remplir un formulaire de déclaration d’intérêts concurrents au moment de la soumission de l’article, 17 (52 %) présentaient une définition de la qualité d’auteur et 5 (15 %) demandaient de détailler les contributions de chaque auteur. Une grille de 40 critères a été élaborée pour définir l’attribution du statut d’auteur. Conclusion : Moins de la moitié des journaux demandait aux auteurs de transmettre un formulaire de déclaration des intérêts concurrents au moment de la soumission d’un article et seulement la moitié des journaux avait donné une définition de la qualité d’auteur. La publication scientifique de travaux sur les pratiques pharmaceutiques n’est pas à l’abri des manques de transparence liés à la publication. L’utilisation d’une grille décrivant la contribution de chaque auteur et la publication en ligne des travaux peuvent contribuer à limiter ces risques. PMID:24970938

  3. L'MISSION INFRA-ROUGE ET LE SCHMA DE NIVEAUX COMMUNS AUX PHOSPHORES ZnS, Cd S, ZnCd S, etc...

    E-print Network

    Paris-Sud XI, Université de

    673 L'ÉMISSION INFRA-ROUGE ET LE SCHÉMA DE NIVEAUX COMMUNS AUX PHOSPHORES ZnS, Cd S, ZnCd S, etc'émission de : A) ZnS-Cu (M 20) ; B) ZnS (50 %) Cd S (50 %) Cu (3 946) ; C) Cd S (4 625). FiG. 2. - Spectre d'excitation de : A) ZnS (4 626) 90 oR ; B) Cd S (4 625) 90 °K, , tation sont identiques aux bandes du spectre d

  4. LES U.E. LIBRES -FICHE DESCRIPTIVE Intitul de l'U.E. : Modlisation d'applications en informatique

    E-print Network

    Sart, Remi

    informatique Objectifs et contenu pédagogiques : Savoir lire une modélisation informatique de problèmes réels ; Savoir modéliser les applications en ayant recours aux outils informatiques. Il s'agit de faire ressortir les usages de l'informatique dans les contextes applicatifs. L'effort sera mis sur les principes de

  5. Phase relations in the system NaCl-KCl-H2O: IV. Differential thermal analysis of the sylvite liquidus in the KCl-H2O binary, the liquidus in the NaCl-KCl-H2O ternary, and the solidus in the NaCl-KCl binary to 2 kb pressure, and a summary of experimental data for thermodynamic-PTX analysis of solid-liquid equilibria at elevated P-T conditions

    USGS Publications Warehouse

    Chou, I.-Ming; Sterner, S.M.; Pitzer, Kenneth S.

    1992-01-01

    The sylvite liquidus in the binary system KCl-H2O and the liquidus in the ternary system NaCl-KCl-H2O were determined by using isobaric differential thermal analysis (DTA) cooling scans at pressures up to 2 kbars. Sylvite solubilities along the three-phase curve in the binary system KCl-H2O were obtained by the intersection of sylvite-liquidus isopleths with the three-phase curve in a P-T plot. These solubility data can be represented by the equation Wt.% KCl (??0.2) = 12.19 + 0.1557T - 5.4071 ?? 10-5 T2, where 400 ??? T ??? 770??C. These data are consistent with previous experimental observations. The solidus in the binary system NaCl-KCl was determined by using isobaric DTA heating scans at pressures up to 2 kbars. Using these liquidus and solidus data and other published information, a thermodynamic-PTX analysis of solid-liquid equilibria at high pressures and temperatures for the ternary system has been performed and is presented in an accompanying paper (Part V of this series). However, all experimental liquidus, solidus, and solvus data used in this analysis are summarized in this report (Part IV) and they are compared with the calculated values based on the analysis. ?? 1992.

  6. L'acceptabilit du placement de marques dans les jeux vido : une application aux joueurs de 15-35 ans

    E-print Network

    Paris-Sud XI, Université de

    to their assiduity (casual vs. hardcore). Gamers admit brand intrusion in games and main results show that a younger acceptability is systematically stronger for hardcore gamers than casual ones. Limits are discussed as main

  7. Developpement d'une methode des caracteristiques tridimensionnelle et application aux calculs de supercellules d'un reacteur CANDU

    NASA Astrophysics Data System (ADS)

    Wu, Guang Jun

    The primary purpose of this study was to construct a new method for determining the cross section increments associated with the reactivity mechanisms in CANDU reactors. Based on the characteristics method, the module MCI is successfully developed and is ready to be integrated in the lattice code DRAGON. The module MCI utilizes non cyclic tracks in a three dimensional transport calculation. The characteristics method allows to resolve the same problems as the collision probabilities method but its main advantage relies on a substantial memory economy. The results of MCI module are similar to those of an EXCELL module in the CANDU-6 calculation scheme. The characteristics method is shown to be equivalent to the collision probability method for the finite domain. A new acceleration technique, the SCR (Self-Collision Rebalancing) technique, was developed using the equivalence of these two methods. When SCR is used with the one parameter variational acceleration method, the resolution converge faster than either of the two. The Tracks Merging Technique (TMT) is a new technique developed within this research to reduce the total number of tracks needed to cover the geometry of the problem studied. The TMT can be used on two levels: TMT-1 and TMT-2. We have observed a factor of four on the reduction of tracks when the TMT was used on the first level and a factor of forty when used on the second level. The TMT could be used without difficulty in the collision probability method. The MCI module was parallelized using the PVM (Parallel Virtual Machine) library for distributed-memory environment. One of four options can be used in the parallel calculation: SPLT, ANGL, STRD and MCRB. Each of the four options is associated with a special load balancing strategy. In the first three options, the load is measured in number of tracks, in the fourth option, the load is dispatched in units of macroband.

  8. Surfaces slectives : proprits optiques et estimation de l'efficacit nergtique dans l'application aux rcepteurs solaires

    E-print Network

    Paris-Sud XI, Université de

    solaires, qui sont capables de réfléchir le rayonnement thermique pro- venant de la surface chauffée du'un récepteur idéal aurait un coefficient de réflexion nul pour le rayonnement solaire, et un coefficient de du rayonnement solaire et l'autre - l'énergie de rayonnement propre de la surface. Par conséquent à

  9. Segr (Gabriel). Au nom du King. Elvis, les fans et l'ethnologue. Montreuil. Aux lieux d'tre (enqutes), 2007, 139 p., 12 .

    E-print Network

    Paris-Sud XI, Université de

    1 Segré (Gabriel). ­ Au nom du King. Elvis, les fans et l'ethnologue. Montreuil. Aux lieux d Au nom du king. Elvis, les fans et l'ethnologue, ce livre regroupe en dix-huit chapitres des notes d où l'ethnologue accompagne les admirateurs à Memphis dans le Tennessee, où est né et a vécu Elvis

  10. Sbastien BROCA, Du logiciel libre aux thories de l'intelligence collective , Revue TIC&Socit, Vol. 2, n 2, 2008, p. 81-101.

    E-print Network

    Paris-Sud XI, Université de

    espérées. En témoignent les occurrences nombreuses des références à la « démocratie open source », à « l'économie open source », voire à la « société open source ». Cette tendance à faire du mouvement du logicielSébastien BROCA, « Du logiciel libre aux théories de l'intelligence collective », Revue TIC

  11. OsIAA6, a member of the rice Aux/IAA gene family, is involved in drought tolerance and tiller outgrowth.

    PubMed

    Jung, Harin; Lee, Dong-Keun; Choi, Yang Do; Kim, Ju-Kon

    2015-07-01

    Auxin signaling is a fundamental part of many plant growth processes and stress responses and operates through Aux/IAA protein degradation and the transmission of the signal via auxin response factors (ARFs). A total of 31 Aux/IAA genes have been identified in rice (Oryza sativa), some of which are induced by drought stress. However, the mechanistic link between Aux/IAA expression and drought responses is not well understood. In this study we found that the rice Aux/IAA gene OsIAA6 is highly induced by drought stress and that its overexpression in transgenic rice improved drought tolerance, likely via the regulation of auxin biosynthesis genes. We observed that OsIAA6 was specifically expressed in the axillary meristem of the basal stem, which is the tissue that gives rise to tillers. A knock-down mutant of OsIAA6 showed abnormal tiller outgrowth, apparently due to the regulation of the auxin transporter OsPIN1 and the rice tillering inhibitor OsTB1. Our results confirm that the OsIAA6 gene is involved in drought stress responses and the control of tiller outgrowth. PMID:26025543

  12. Jean-Louis Tornatore et Sbastien Paul, Publics ou populations? La dmocratie culturelle en question, de l'utopie comusale aux espaces intermdiaires, in Olivier Donnat et Paul

    E-print Network

    Boyer, Edmond

    , de l'utOpie écomuséale aux « espaces intermédiaires» Initié par le secrétaire d'État au patrimoine et plus souvent laisse de côté et qui a trait, s'agissant de territoires en déshérence et d'architectures patrimoine dans la mise en culture des friches industrielles Si on suspend provisoirement - parce que

  13. tique sont polarises, rectilignement si l'mission a lieu perpendicu-lairement aux lignes de force, et circulairement si elle a lieu dans

    E-print Network

    Paris-Sud XI, Université de

    dans des bouchons métalliques, puis entre deux plaques d'aluminium parallèles reliées aux deux pôles d'une batterie d'accumulateurs et viennent enfin marquer leur arri- vée au fond du tube par une tache : la plaque supérieure communique avec un pôle d'une batterie d'accumulateurs, l'inférieure est reliée

  14. A single coil radio frequency gradient probe for nuclear magnetic resonance applications

    NASA Astrophysics Data System (ADS)

    Christofield, N.; Sobieski, D. N.; Erker, J. C.; May, S.; Augustine, M. P.

    2012-12-01

    A single coil nuclear magnetic resonance (NMR) probehead and associated electronics capable of asynchronously applying both homogeneous and inhomogeneous radio frequency (rf) pulses to solid, liquid, or gaseous samples is described. This equipment can be interfaced with a conventional single channel NMR spectrometer. Carefully placed PIN diodes on the NMR probehead are used to switch the coil between a homogeneous end tapped configuration and an inhomogeneous center tapped rf gradient configuration. This approach dramatically improves channel isolation in comparison to existing two coil designs. Descriptions of the new probehead, the transistor-transistor logic (TTL) controlled dc pulser for PIN diode gating, and the high power rf switch are provided. Several NMR pulse sequences are used to test the channel isolation and probe performance. Finally an application to liquid phase solvent suppression is provided.

  15. Application d'un modèle bayesien de détection de changements de moyennes dans une série

    Microsoft Academic Search

    PIERRE BRUNEAU; JEAN-CLAUDE CLAUDE

    1983-01-01

    Par l'application d'un modèle bayesien sur une série chronologique de débits observés sur la rivière Sainte-Anne du Nord, il a été possible d'identifier l'influence de la mise en eau et de l'exploitation de quatre réservoirs sur les séries mensuelles en terme d'un changement ? dans la moyenne au moment ? L'application du même modèle aux séries de deux bassins témoins

  16. Séroprévalence et facteurs associés au VIH et aux hépatites virales B et C dans la ville de Bafoussam au Cameroun

    PubMed Central

    Mbopi-Keou, Francois-Xavier; Nkala, Isabelle Vanessa Monthe; Kalla, Ginette Claude Mireille; Nguefack-Tsague, Georges; Kamga, Hortense Gonsu; Noubom, Michel; Mvogo, Côme Ebana; Sosso, Maurice Aurelien

    2015-01-01

    Introduction L'objectif de ce travail était de déterminer la séroprévalence et les facteurs associés au VIH et aux hépatites virales B et C dans la ville de Bafoussam au Cameroun. Méthodes Il s'agissait d'une étude descriptive et analytique réalisée de février 2012 à Juin 2012 dans la ville de Bafoussam au Cameroun. Pour cette étude, nous avons obtenu une clairance éthique. Résultats Au total, 982 personnes ont été dépistées pour le VIH et les hépatites virales B et C. Les femmes représentaient 56,3% des personnes dépistées. La tranche d’âge la plus représentée était celle des 20 à 24 ans. L’âge médian était de 34,5 ans. Les prévalences du VIH, de l'AgHBs, et de l'Ac anti HCV étaient respectivement de 6,0%, 4,1%, et 0,4%. La prévalence du VIH était 2 fois plus élevée parmi les femmes que les hommes avec 8,1% contre 3,5% (p=0,01). Les prévalences les plus élevées ont été observées chez les personnes de 30 à 34 ans, 40 à 44 ans avec 15,0% et 11,5% (p=0,01), les personnes sans emploi avec 11,1% (p<0,001) et les personnes en union libre avec 17,9% (p=0,000). La prévalence du VIH n’était pas directement liée aux comportements et pratiques sexuels de la population de l’étude. On enregistrait une prévalence élevée de 29,3% chez les individus ayant déclaré avoir au moins une infection sexuellement transmissible (p=0,000). Conclusion Il apparait urgent de mettre en place des stratégies de prévention contre le VIH, les hépatites virales et les facteurs associés au Cameroun.

  17. The French Tsunami warning center for the Mediterranean and North-East Atlantic (CENtre d'ALerte aux Tsunamis, CENALT)

    NASA Astrophysics Data System (ADS)

    Schindelé, F.; Bossu, R.; Alabrune, N.; Arnoul, P.; Duperray, P.; Gailler, A.; Guilbert, J.; Hébert, H.; Hernandez, B.; Loevenbruck, A.; Roudil, P.

    2012-04-01

    The CENALT (CENtre d'Alerte aux Tsunamis) is responsible for the French NTWC (National Tsunami Warning Center). This center was established through a project that was requested by the French Ministry of Interior and the Ministry of Sustainable Development. It is implemented by the Commissariat à l'énergie atomique et aux énergies alternatives (CEA), the French Hydrographic and Oceanographic Service (SHOM) and the Centre National de la Recherche Scientifique (CNRS), and is based in Bruyères-le-Châtel (30 km from Paris). This center is based on three main components: seismic network data, sea level network data, dissemination system and processing and analyzing softwares and is operating on a 24/7 basis. The CENALT has established scientific cooperation with 8 institutions and implemented and funded private leased lines to exchange data with institutions from 5 different European countries (Germany, Italy, Portugal, Spain, Tunisia). The seismic data are processed with the Seiscomp 3 software. SHOM is working on making all French tide-gauge stations operated and available in real-time in 2012, and they installed 5 new tide gage stations. The tide gage data will be processed with a customized version of the Guitar (Gempa) software allowing the detection of tsunami signals, complemented by other softwares developed by the CEA. Historical tsunami databases (sources and observations) and earthquake databases, mostly based on available international databases, have been synthetized by CEA to produce information maps in real time, used to guide operators of permanence. Precomputed tsunami scenarios are implemented to build in real time maps of the highest tsunami impact expected in deep water. Along with an optimized tsunami modeling tool, these softwares help to define the areas where the tsunami may be observed and cause damage. The CENALT has been operating since early January 2012 as a pre-operational service and will be fully operational in July 2012. It is also ready to act as Candidate Watch Provider covering Western Mediterranean by July 2012.

  18. Arabidopsis SHR and SCR transcription factors and AUX1 auxin influx carrier control the switch between adventitious rooting and xylogenesis in planta and in in vitro cultured thin cell layers

    PubMed Central

    Della Rovere, F.; Fattorini, L.; D’Angeli, S.; Veloccia, A.; Del Duca, S.; Cai, G.; Falasca, G.; Altamura, M. M.

    2015-01-01

    Background and Aims Adventitious roots (ARs) are essential for vegetative propagation. The Arabidopsis thaliana transcription factors SHORT ROOT (SHR) and SCARECROW (SCR) affect primary/lateral root development, but their involvement in AR formation is uncertain. LAX3 and AUX1 auxin influx carriers contribute to primary/lateral root development. LAX3 expression is regulated by SHR, and LAX3 contributes to AR tip auxin maximum. In contrast, AUX1 involvement in AR development is unknown. Xylogenesis is induced by auxin plus cytokinin as is AR formation, but the genes involved are largely unknown. Stem thin cell layers (TCLs) form ARs and undergo xylogenesis under the same auxin plus cytokinin input. The aim of this research was to investigate SHR, SCR, AUX1 and LAX3 involvement in AR formation and xylogenesis in intact hypocotyls and stem TCLs in arabidopsis. Methods Hypocotyls of scr-1, shr-1, lax3, aux1-21 and lax3/aux1-21 Arabidopsis thaliana null mutant seedlings grown with or without auxin plus cytokinin were examined histologically, as were stem TCLs cultured with auxin plus cytokinin. SCR and AUX1 expression was monitored using pSCR::GFP and AUX1::GUS lines, and LAX3 expression and auxin localization during xylogenesis were monitored by using LAX3::GUS and DR5::GUS lines. Key Results AR formation was inhibited in all mutants, except lax3. SCR was expressed in pericycle anticlinally derived AR-forming cells of intact hypocotyls, and in cell clumps forming AR meristemoids of TCLs. The apex was anomalous in shr and scr ARs. In all mutant hypocotyls, the pericycle divided periclinally to produce xylogenesis. Xylary element maturation was favoured by auxin plus cytokinin in shr and aux1-21. Xylogenesis was enhanced in TCLs, and in aux1-21 and shr in particular. AUX1 was expressed before LAX3, i.e. in the early derivatives leading to either ARs or xylogenesis. Conclusions AR formation and xylogenesis are developmental programmes that are inversely related, but they involve fine-tuning by the same proteins, namely SHR, SCR and AUX1. Pericycle activity is central for the equilibrium between xylary development and AR formation in the hypocotyl, with a role for AUX1 in switching between, and balancing of, the two developmental programmes. PMID:25617411

  19. APPLICATION APPLICATION

    E-print Network

    Jain, Raj

    in the network has three layers: physical layer, datalink layer (DLC) and application layer. Nodes in the network these entities communicate with one another, and will develop a DLC layer entity that performs error correction communicates through Protocol Data Units (PDU). The application layer PDU is called A_PDU, the DLC PDU

  20. APPLICATION APPLICATION

    E-print Network

    Jain, Raj

    that each node in the network has three layers: physical layer, datalink layer (DLC) and application layer will learn how these entities communicate with one another, and will develop a simple DLC layer entity (PDU). The application layer PDU is called A_PDU, the DLC PDU is called D_PDU, and the physical layer

  1. Application of PTR-MS for measuring odorant emissions from soil application of manure slurry.

    PubMed

    Feilberg, Anders; Bildsoe, Pernille; Nyord, Tavs

    2015-01-01

    Odorous volatile organic compounds (VOC) and hydrogen sulfide (H2S) are emitted together with ammonia (NH3) from manure slurry applied as a fertilizer, but little is known about the composition and temporal variation of the emissions. In this work, a laboratory method based on dynamic flux chambers packed with soil has been used to measure emissions from untreated pig slurry and slurry treated by solid-liquid separation and ozonation. Proton-transfer-reaction mass spectrometry (PTR-MS) was used to provide time resolved data for a range of VOC, NH3 and H2S. VOC included organic sulfur compounds, carboxylic acids, phenols, indoles, alcohols, ketones and aldehydes. H2S emission was remarkably observed to take place only in the initial minutes after slurry application, which is explained by its high partitioning into the air phase. Long-term odor effects are therefore assessed to be mainly due to other volatile compounds with low odor threshold values, such as 4-methylphenol. PTR-MS signal assignment was verified by comparison to a photo-acoustic analyzer (NH3) and to thermal desorption GC/MS (VOC). Due to initial rapid changes in odorant emissions and low concentrations of odorants, PTR-MS is assessed to be a very useful method for assessing odor following field application of slurry. The effects of treatments on odorant emissions are discussed. PMID:25585103

  2. Application of PTR-MS for Measuring Odorant Emissions from Soil Application of Manure Slurry

    PubMed Central

    Feilberg, Anders; Bildsoe, Pernille; Nyord, Tavs

    2015-01-01

    Odorous volatile organic compounds (VOC) and hydrogen sulfide (H2S) are emitted together with ammonia (NH3) from manure slurry applied as a fertilizer, but little is known about the composition and temporal variation of the emissions. In this work, a laboratory method based on dynamic flux chambers packed with soil has been used to measure emissions from untreated pig slurry and slurry treated by solid-liquid separation and ozonation. Proton-transfer-reaction mass spectrometry (PTR-MS) was used to provide time resolved data for a range of VOC, NH3 and H2S. VOC included organic sulfur compounds, carboxylic acids, phenols, indoles, alcohols, ketones and aldehydes. H2S emission was remarkably observed to take place only in the initial minutes after slurry application, which is explained by its high partitioning into the air phase. Long-term odor effects are therefore assessed to be mainly due to other volatile compounds with low odor threshold values, such as 4-methylphenol. PTR-MS signal assignment was verified by comparison to a photo-acoustic analyzer (NH3) and to thermal desorption GC/MS (VOC). Due to initial rapid changes in odorant emissions and low concentrations of odorants, PTR-MS is assessed to be a very useful method for assessing odor following field application of slurry. The effects of treatments on odorant emissions are discussed. PMID:25585103

  3. Recent advances in vacuum sciences and applications

    NASA Astrophysics Data System (ADS)

    Mozeti?, M.; Ostrikov, K.; Ruzic, D. N.; Curreli, D.; Cvelbar, U.; Vesel, A.; Primc, G.; Leisch, M.; Jousten, K.; Malyshev, O. B.; Hendricks, J. H.; Kövér, L.; Tagliaferro, A.; Conde, O.; Silvestre, A. J.; Giapintzakis, J.; Buljan, M.; Radi?, N.; Draži?, G.; Bernstorff, S.; Biederman, H.; Kylián, O.; Hanuš, J.; Miloševi?, S.; Galtayries, A.; Dietrich, P.; Unger, W.; Lehocky, M.; Sedlarik, V.; Stana-Kleinschek, K.; Drmota-Petri?, A.; Pireaux, J. J.; Rogers, J. W.; Anderle, M.

    2014-04-01

    Recent advances in vacuum sciences and applications are reviewed. Novel optical interferometer cavity devices enable pressure measurements with ppm accuracy. The innovative dynamic vacuum standard allows for pressure measurements with temporal resolution of 2 ms. Vacuum issues in the construction of huge ultra-high vacuum devices worldwide are reviewed. Recent advances in surface science and thin films include new phenomena observed in electron transport near solid surfaces as well as novel results on the properties of carbon nanomaterials. Precise techniques for surface and thin-film characterization have been applied in the conservation technology of cultural heritage objects and recent advances in the characterization of biointerfaces are presented. The combination of various vacuum and atmospheric-pressure techniques enables an insight into the complex phenomena of protein and other biomolecule conformations on solid surfaces. Studying these phenomena at solid-liquid interfaces is regarded as the main issue in the development of alternative techniques for drug delivery, tissue engineering and thus the development of innovative techniques for curing cancer and cardiovascular diseases. A review on recent advances in plasma medicine is presented as well as novel hypotheses on cell apoptosis upon treatment with gaseous plasma. Finally, recent advances in plasma nanoscience are illustrated with several examples and a roadmap for future activities is presented.

  4. Contrle de la conformit de l'information financire des socits cotes aux normes

    E-print Network

    Paris-Sud XI, Université de

    européen où les normes IFRS sont devenues obligatoires pour la préparation des états financiers consolidés surveillance de l'application des normes IFRS par les régulateurs, à notre connaissance, peu de travaux, normes comptables, IFRS, régulateur Enforcement of accounting standards by the AMF in France

  5. Engagement pdagogique relatif aux stages en entreprise organiss en master ingnieur en informatique

    E-print Network

    Ernst, Damien

    informatique Objectif du stage Le stage a pour objet essentiel l'application pratique en entreprise des enseignements organisés en sciences informatiques à l'Université de Liège. Pré-requis Etre inscrit en 2ème épreuve du master en ingénieur en informatique. Organisation Le stage en entreprise aura une durée

  6. Les isotopes et le tracage de l'eau dans LMDZ: status et exemples d'applications recentes

    E-print Network

    Madeleine, Jean-Baptiste

    -iso 3 axes: 1. pal´eo-climats 2. processus atmosph´eriques 3. hydrologie continentale 4/9 #12;Axe 1 Ð ¾Ü Ǿ Ñ Ò Ô ÒØ × Ð Ñ Ø× Ù × T ´Ãµ Ä Å Ð Ñ Ô Masson-Delmotte et al 2011 5/9 #12;Axe 1: applications/9 #12;Axe 1: applications pal´eo: aux p^oles + -15 -10 -5 0 5 10 -8 -6 -4 -2 0 2 4 riche pauvre ØÖ Ð³ Ù

  7. Phenotypes associated with down-regulation of Sl-IAA27 support functional diversity among Aux/IAA family members in tomato.

    PubMed

    Bassa, Carole; Mila, Isabelle; Bouzayen, Mondher; Audran-Delalande, Corinne

    2012-09-01

    The phytohormone auxin is known to regulate several aspects of plant development, and Aux/IAA transcription factors play a pivotal role in auxin signaling. To extend our understanding of the multiple functions of Aux/IAAs further, the present study describes the functional characterization of Sl-IAA27, a member of the tomato Aux/IAA gene family. Sl-IAA27 displays a distinct behavior compared with most Aux/IAA genes regarding the regulation of its expression by auxin, and the Sl-IAA27-encoded protein harbors a unique motif of unknown function also present in Sl-IAA9 and remarkably conserved in monocot and dicot species. Tomato transgenic plants underexpressing the Sl-IAA27 gene revealed multiple phenotypes related to vegetative and reproductive growth. Silencing of Sl-IAA27 results in higher auxin sensitivity, altered root development and reduced Chl content in leaves. Both ovule and pollen display a dramatic loss of fertility in Sl-IAA27 down-regulated lines, and the internal anatomy of the flower and the fruit are modified, with an enlarged placenta in smaller fruits. In line with the reduced Chl content in Sl-IAA27 RNA interference (RNAi) leaves, genes involved in Chl synthesis display lower expression at the level of transcript accumulation. Even though Sl-IAA27 is closely related to Sl-IAA9 in terms of sequence homology and the encoded proteins share common structural features, the data indicate that the two genes regulate tomato fruit initiation and development in a distinct manner. PMID:22764281

  8. Un rve chimrique : la clture du dbat autour de l'enseignement oral de Le prsent article fait suite nos deux publications en rponse aux objections

    E-print Network

    Paris-Sud XI, Université de

    article fait suite à nos deux publications en réponse aux objections émises par L. Brisson1 et relatives »3 . Comme L. Brisson tente à présent, dans un article intitulé « Vingt ans après »4 , de clore un ultimes arguments invoqués par L. Brisson pour statuer sur leur degré de pertinence. a) L'oralité et l

  9. TUDE AUX RAYONS X, PAR DIFFRACTION NEUTRONIQUE ET PAR EFFET MSSBAUER DES SOLUTIONS SOLIDES Ba(FexGa1-x)2O4

    E-print Network

    Paris-Sud XI, Université de

    509 ÉTUDE AUX RAYONS X, PAR DIFFRACTION NEUTRONIQUE ET PAR EFFET MÖSSBAUER DES SOLUTIONS SOLIDES Ba Ba(FexGa1-x)2O4. Comme pour l'étude de la solution solide Ba(FexAl1-x)2O4, nous avons mis en évidence diffraction and Mössbauer effect the solid solu- tion Ba(FexGa1-x)2O4. As in the study of the solid solution

  10. Observation of linear to planar structural transition in sulfur-doped gold clusters: Au(x)S- (x = 2-5).

    PubMed

    Wen, Hui; Liu, Yi-Rong; Huang, Teng; Xu, Kang-Ming; Zhang, Wei-Jun; Huang, Wei; Wang, Lai-Sheng

    2013-05-01

    We report a joint experimental and theoretical study on the structures of a series of gold clusters doped with a sulfur atom, Au(x)S(-) (x = 2-5). Well-resolved photoelectron spectra are obtained and compared with theoretical results calculated using several density functional methods to elucidate the structures and bonding of Au(x)S(-) (x = 2-5). Au2S(-) is found to have an asymmetric linear global minimum structure with C(?v) symmetry, while the most stable structure of neutral Au2S is bent with C(2v) symmetry, reminiscent of H2S. Au3S(-) is found to have an asymmetric bent structure with an Au-S-Au-Au connectivity. Two isomers are observed experimentally to co-exist for Au4S(-): a symmetric bent 1D structure (C(2v)) and a 2D planar low-lying isomer (C(s)). The global minimum of Au5S(-) is found to be a highly stable planar triangular structure (C(2v)). Thus, a 1D-to-2D structural transition is observed in the Au(x)S(-) clusters as a function of x at x = 4. Molecular orbital analyses are carried out to obtain insight into the nature of the chemical bonding in the S-doped gold clusters. Strong covalent bonding between S and Au is found to be responsible for the 1D structures of Au(x)S(-) (x = 2-4), whereas delocalized Au-Au interactions favor the 2D planar structure for the larger Au5S(-) cluster. PMID:23656130

  11. Outrepasser les limites des techniques classiques de Prise d'Empreintes grace aux Reseaux de Neurones

    E-print Network

    Burroni, Javier

    2010-01-01

    We present an application of Artificial Intelligence techniques to the field of Information Security. The problem of remote Operating System (OS) Detection, also called OS Fingerprinting, is a crucial step of the penetration testing process, since the attacker (hacker or security professional) needs to know the OS of the target host in order to choose the exploits that he will use. OS Detection is accomplished by passively sniffing network packets and actively sending test packets to the target host, to study specific variations in the host responses revealing information about its operating system. The first fingerprinting implementations were based on the analysis of differences between TCP/IP stack implementations. The next generation focused the analysis on application layer data such as the DCE RPC endpoint information. Even though more information was analyzed, some variation of the "best fit" algorithm was still used to interpret this new information. Our new approach involves an analysis of the compos...

  12. Methodologie de conception appliquee aux syst`emes de radiocommunications de quatri`eme generation

    E-print Network

    Paris-Sud XI, Université de

    .massiani@insa-rennes.fr fabienne.nouvel@insa-rennes.fr R´esum´e : Ce papier pr´esente l'application de l'ap- proche MCSE et de l contexte de la M´ethodologie pour la Conception de Syst`emes Electroniques (MCSE) [Calvez, 1990] peut se r´ev`eler particuli`erement int´eressante. Ce papier vise donc `a illustrer l'int´er^et de l'approche MCSE pour la

  13. The PB1 Domain in Auxin Response Factor and Aux/IAA Proteins: A Versatile Protein Interaction Module in the Auxin Response[OPEN

    PubMed Central

    2015-01-01

    An integral part of auxin-regulated gene expression involves the interplay of two types of transcription factors, the DNA binding auxin response factor (ARF) activators and the interacting auxin/indole acetic acid (Aux/IAA) repressors. Insight into the mechanism of how these transcription factors interact with one another has recently been revealed from crystallographic information on ARF5 and ARF7 C-terminal domains (i.e., a protein-protein interaction domain referred to as domain III/IV that is related to domain III/IV in Aux/IAA proteins). Three-dimensional structures showed that this domain in ARF5 and ARF7 conforms to a well-known PB1 (Phox and Bem1) domain that confers protein-protein interactions with other PB1 domain proteins through electrostatic contacts. Experiments verifying the importance of charged amino acids in conferring ARF and Aux/IAA interactions have confirmed the PB1 domain structure. Some in planta experiments designed to test the validity of PB1 interactions in the auxin response have led to updated models for auxin-regulated gene expression and raised many questions that will require further investigation. In addition to the PB1 domain, a second protein interaction module that functions in ARF-ARF dimerization and facilitates DNA binding has recently been revealed from crystallography studies on the ARF1 and ARF5 DNA binding domains. PMID:25604444

  14. Developpement d'une plateforme de calcul d'equilibres chimiques complexes et adaptation aux problemes electrochimiques et d'equilibres contraints

    NASA Astrophysics Data System (ADS)

    Neron, Alex

    Avec l'arrivée de l'environnement comme enjeu mondial, le secteur de l'efficacité énergétique prend une place de plus en plus importante pour les entreprises autant au niveau économique que pour l'image de la compagnie. Par le fait même, le domaine des technologies de l'énergie est un créneau de recherche dont les projets en cours se multiplient. D'ailleurs, un des problèmes qui peut survenir fréquemment dans certaines entreprises est d'aller mesurer la composition des matériaux dans des conditions difficiles d'accès. C'est le cas par exemple de l'électrolyse de l'aluminium qui se réalise à des températures très élevées. Pour pallier à ce problème, il faut créer et valider des modèles mathématiques qui vont calculer la composition et les propriétés à l'équilibre du système chimique. Ainsi, l'objectif global du projet de recherche est de développer un outil de calcul d'équilibres chimiques complexes (plusieurs réactions et plusieurs phases) et l'adapter aux problèmes électrochimiques et d'équilibres contraints. Plus spécifiquement, la plateforme de calcul doit tenir compte de la variation de température due à un gain ou une perte en énergie du système. Elle doit aussi considérer la limitation de l'équilibre due à un taux de réaction et enfin, résoudre les problèmes d'équilibres électrochimiques. Pour y parvenir, les propriétés thermodynamiques telles que l'énergie libre de Gibbs, la fugacité et l'activité sont tout d'abord étudiées pour mieux comprendre les interactions moléculaires qui régissent les équilibres chimiques. Ensuite, un bilan énergétique est inséré à la plateforme de calcul, ce qui permet de calculer la température à laquelle le système est le plus stable en fonction d'une température initiale et d'une quantité d'énergie échangée. Puis, une contrainte cinétique est ajoutée au système afin de calculer les équilibres pseudo-stationnaires en évolution dans le temps. De plus, la contrainte d'un champ de potentiel électrique est considérée pour l'évaluation des équilibres électrochimiques par des techniques classiques de résolution et fera l'objet de travaux futurs via une technique d'optimisation. Enfin, les résultats obtenus sont comparés avec ceux présents dans la littérature scientifique pour valider le modèle. À terme, le modèle développé devient tin bon moyen de prédire des résultats en éliminant beaucoup de coût en recherche et développement. Les résultats ainsi obtenus sont applicables dans une grande variété de domaines tels que la chimie et l'électrochimie industrielle ainsi que la métallurgie et les matériaux. Ces applications permettraient de réduire la production de gaz à effet de serre en optimisant les procédés et en ayant une meilleure efficacité énergétique. Mots-clés : Systèmes énergétiques avancés, Équilibre thermodynamique, Équilibre contraint, Optimisation, Minimisation de l'énergie libre de Gibbs.

  15. A study of the applicability of nucleation theory to quasi-thermodynamic transitions of second and higher Ehrenfest-order, supplement 3

    NASA Technical Reports Server (NTRS)

    Barker, R. E., Jr.

    1986-01-01

    The work includes an investigation of the applicability of the nucleation theory to second and higher order thermodynamic transitions in the Ehrenfest sense, and a number of significant conclusions relevant to first order transitions, as well. The underlying theoretical method consisted of expanding the Gibbs' free energy in a Maclarin or Taylor series and then using fundamental thermodynamic determinable quantities, and interpreting the results. Work was performed on the existence and interpretation of an interfacial energy between phases in a second order transition in addition to an investigation of the solid-liquid interfacial energy for various polymers. Extensive considerations were devoted to various aspects of a particular polymer, polyvinylidene fluoride (PVDF or PVF2), including an experimetal investigation of the effects of an applied electric field on the morphology of melt crystallization and on the nucleation and growth of polarized domains.

  16. Algorithme d'adaptation du filtre de Kalman aux variations soudaines de bruit

    NASA Astrophysics Data System (ADS)

    Canciu, Vintila

    This research targets the case of Kalman filtering as applied to linear time-invariant systems having unknown process noise covariance and measurement noise covariance matrices and addresses the problem represented by the incomplete a priori knowledge of these two filter initialization parameters. The goal of this research is to determine in realtime both the process covariance matrix and the noise covariance matrix in the context of adaptive Kalman filtering. The resultant filter, called evolutionary adaptive Kalman filter, is able to adapt to sudden noise variations and constitutes a hybrid solution for adaptive Kalman filtering based on metaheuristic algorithms. MATLAB/Simulink simulation using several processes and covariance matrices plus comparison with other filters was selected as validation method. The Cramer-Rae Lower Bound (CRLB) was used as performance criterion. The thesis begins with a description of the problem under consideration (the design of a Kalman filter that is able to adapt to sudden noise variations) followed by a typical application (INS-GPS integrated navigation system) and by a statistical analysis of publications related to adaptive Kalman filtering. Next, the thesis presents the current architectures of the adaptive Kalman filtering: the innovation adaptive estimator (IAE) and the multiple model adaptive estimator (MMAE). It briefly presents their formulation, their behavior, and the limit of their performances. The thesis continues with the architectural synthesis of the evolutionary adaptive Kalman filter. The steps involved in the solution of the problem under consideration is also presented: an analysis of Kalman filtering and sub-optimal filtering methods, a comparison of current adaptive Kalman and sub-optimal filtering methods, the emergence of evolutionary adaptive Kalman filter as an enrichment of sub-optimal filtering with the help of biological-inspired computational intelligence methods, and the step-by-step architectural synthesis of the evolutionary adaptive Kalman filter. Next, the thesis describes all the aspects related to MATLAB/Simulink modeling and simulation: the performance criterion represented by the Cramer-Rae Lower Bound, the step-by-step modeling of the evolutionary adaptive Kalman filter, and the simulation results that confirm the viability of this approach. The thesis ends with the conclusion and the references. The appendices (the mathematical model of a 6DoF Inertial Measurement Unit, the experimental setup, the Simulink diagrams/MATLAB programs that constitute the evolutionary adaptive Kalman filter, plus the simulation results) are regrouped in a separate document.

  17. Multiple AUX/IAA-ARF modules regulate lateral root formation: the role of Arabidopsis SHY2/IAA3-mediated auxin signalling.

    PubMed

    Goh, Tatsuaki; Kasahara, Hiroyuki; Mimura, Tetsuro; Kamiya, Yuji; Fukaki, Hidehiro

    2012-06-01

    In Arabidopsis thaliana, lateral root (LR) formation is regulated by multiple auxin/indole-3-acetic acid (Aux/IAA)-AUXIN RESPONSE FACTOR (ARF) modules: (i) the IAA28-ARFs module regulates LR founder cell specification; (ii) the SOLITARY-ROOT (SLR)/IAA14-ARF7-ARF19 module regulates nuclear migration and asymmetric cell divisions of the LR founder cells for LR initiation; and (iii) the BODENLOS/IAA12-MONOPTEROS/ARF5 module also regulates LR initiation and organogenesis. The number of Aux/IAA-ARF modules involved in LR formation remains unknown. In this study, we isolated the shy2-101 mutant, a gain-of-function allele of short hypocotyl2/suppressor of hy2 (shy2)/iaa3 in the Columbia accession. We demonstrated that the shy2-101 mutation not only strongly inhibits LR primordium development and emergence but also significantly increases the number of LR initiation sites with the activation of LATERAL ORGAN BOUNDARIES-DOMAIN16/ASYMMETRIC LEAVES2-LIKE18, a target gene of the SLR/IAA14-ARF7-ARF19 module. Genetic analysis revealed that enhanced LR initiation in shy2-101 depended on the SLR/IAA14-ARF7-ARF19 module. We also showed that the shy2 roots contain higher levels of endogenous IAA. These observations indicate that the SHY2/IAA3-ARF-signalling module regulates not only LR primordium development and emergence after SLR/IAA14-ARF7-ARF19 module-dependent LR initiation but also inhibits LR initiation by affecting auxin homeostasis, suggesting that multiple Aux/IAA-ARF modules cooperatively regulate the developmental steps during LR formation. PMID:22527388

  18. Methode des elements finis hybride appliquee aux vibrations des coques spheriques

    NASA Astrophysics Data System (ADS)

    Menaa, Mohamed

    The analysis of spherical shells filled with fluid and subjected to supersonic flow has been the subject of few research. Most of these studies treat the dynamic behaviour of empty shells. Few works have investigated spherical shells filled with fluid or subjected to supersonic flutter. In this thesis, we propose to develop a model to analyse the vibratory behaviour of both empty spherical shells and partially filled with fluid. This model is also applicable to study of the dynamic stability of spherical shells subjected to supersonic flow. The model developed is a combination of finite element method, thin shell theory, potential fluid theory and aerodynamic fluid theory. Different parameters are considered here in this study. In the first part of this study, free vibration analysis of spherical shell is carried out. The structural model is based on a combination of thin shell theory and the classical finite element method. Free vibration equations using the hybrid finite element formulation are derived and solved numerically. The results are validated using numerical and theoretical data available in the literature. The analysis is accomplished for spherical shells of different geometries, boundary conditions and radius to thickness ratios. This proposed hybrid finite element method can be used efficiently for design and analysis of spherical shells employed in high speed aircraft structures. In the second part of the present study, a hybrid finite element method is applied to investigate the free vibration of spherical shell filled with fluid. The structural model is based on a combination of thin shell theory and the classical finite element method. It is assumed that the fluid is incompressible and has no free-surface effect. Fluid is considered as a velocity potential variable at each node of the shell element where its motion is expressed in terms of nodal elastic displacement at the fluid-structure interface. Numerical simulation is done and vibration frequencies for different filling ratios are obtained and compared with existing experimental and theoretical results. The dynamic behavior for different shell geometries, filling ratios and boundary conditions with different radius to thickness ratios is summarized. This proposed hybrid finite element method can be used efficiently for analyzing the dynamic behavior of aerospace structures at less computational cost than other commercial FEM software. In this study, aeroelastic analysis of a spherical shell subjected to the external supersonic airflow is carried out. The structural model is based on a combination of linear spherical shell theory and the classic finite element method. In this hybrid method, the nodal displacements are found from the exact solution of shell governing equations rather than approximated by polynomial functions. Linearized first-order potential (piston) theory with the curvature correction term is coupled with the structural model to account for pressure loading. Linear mass, stiffness and damping matrices are found using the hybrid finite element formulation. Aeroelastic equations are derived and solved numerically. The results are validated using numerical and theoretical data available in the literature. The analysis is accomplished for spherical shells of different boundary conditions, geometries, flow parameters and radius to thickness ratios. Results show that the spherical shell loses its stability through coupled-mode flutter. This proposed hybrid finite element method can be used efficiently for design and analysis of spherical shells employed in high speed aircraft structures.

  19. Transaction Logs and Search Patterns on a Children's Portal \\/ Journaux de transaction et modes de recherche sur un portail web destiné aux enfants

    Microsoft Academic Search

    Jamshid Beheshti; Andrew Large; Marni Tam

    2010-01-01

    RésuméRésumé Les journaux de transactions d'un portail web destiné aux enfants ont été analysés dans le but de dégager les modes de recherche lorsque les utilisateurs du système disposent de quatre choix de recherche. Les résultats montrent que la taxinomie des sujets et les options de recherche alphabétique comptent pour 83 pour cent de toutes les recherches, ce qui indique

  20. Transaction Logs and Search Patterns on a Children's Portal \\/ Journaux de transaction et modes de recherche sur un portail web destiné aux enfants

    Microsoft Academic Search

    Jamshid Beheshti; Andrew Large; Marni Tam

    2010-01-01

    Résumé:Les journaux de transactions d'un portail web destiné aux enfants ont été analysés dans le but de dégager les modes de recherche lorsque les utilisateurs du système disposent de quatre choix de recherche. Les résultats montrent que la taxinomie des sujets et les options de recherche alphabétique comptent pour 83 pour cent de toutes les recherches, ce qui indique une

  1. LATERAL ROOT PRIMORDIA 1 of maize acts as a transcriptional activator in auxin signalling downstream of the Aux/IAA gene rootless with undetectable meristem 1

    PubMed Central

    Zhang, Yanxiang; von Behrens, Inga; Zimmermann, Roman; Ludwig, Yvonne; Hey, Stefan; Hochholdinger, Frank

    2015-01-01

    Only little is known about target genes of auxin signalling downstream of the Aux/IAA-ARF module. In the present study, it has been demonstrated that maize lateral root primordia 1 (lrp1) encodes a transcriptional activator that is directly regulated by the Aux/IAA protein ROOTLESS WITH UNDETECTABLE MERISTEM 1 (RUM1). Expression of lrp1 is confined to early root primordia and meristems and is auxin-inducible. Based on its primary protein structure, LRP1 is predicted to be a transcription factor. This notion is supported by exclusive LRP1 localization in the nucleus and its ability to activate downstream gene activity. Based on the observation that lrp1 transcription is completely repressed in the semi-dominant gain of function mutant rum1, it was demonstrated that the lrp1 promoter is a direct target of RUM1 proteins. Subsequently, promoter activation assays indicated that RUM1 represses the expression of a GFP reporter fused to the native promoter of lrp1. Constitutive repression of lrp1 in rum1 mutants is a consequence of the stability of mutated rum1 proteins which cannot be degraded by the proteasome and thus constitutively bind to the lrp1 promoter and repress transcription. Taken together, the repression of the transcriptional activator lrp1 by direct binding of RUM1 to its promoter, together with specific expression of lrp1 in root meristems, suggests a function in maize root development via the RUM1-dependent auxin signalling pathway. PMID:25911745

  2. LATERAL ROOT PRIMORDIA 1 of maize acts as a transcriptional activator in auxin signalling downstream of the Aux/IAA gene rootless with undetectable meristem 1.

    PubMed

    Zhang, Yanxiang; Behrens, Inga von; Zimmermann, Roman; Ludwig, Yvonne; Hey, Stefan; Hochholdinger, Frank

    2015-07-01

    Only little is known about target genes of auxin signalling downstream of the Aux/IAA-ARF module. In the present study, it has been demonstrated that maize lateral root primordia 1 (lrp1) encodes a transcriptional activator that is directly regulated by the Aux/IAA protein ROOTLESS WITH UNDETECTABLE MERISTEM 1 (RUM1). Expression of lrp1 is confined to early root primordia and meristems and is auxin-inducible. Based on its primary protein structure, LRP1 is predicted to be a transcription factor. This notion is supported by exclusive LRP1 localization in the nucleus and its ability to activate downstream gene activity. Based on the observation that lrp1 transcription is completely repressed in the semi-dominant gain of function mutant rum1, it was demonstrated that the lrp1 promoter is a direct target of RUM1 proteins. Subsequently, promoter activation assays indicated that RUM1 represses the expression of a GFP reporter fused to the native promoter of lrp1. Constitutive repression of lrp1 in rum1 mutants is a consequence of the stability of mutated rum1 proteins which cannot be degraded by the proteasome and thus constitutively bind to the lrp1 promoter and repress transcription. Taken together, the repression of the transcriptional activator lrp1 by direct binding of RUM1 to its promoter, together with specific expression of lrp1 in root meristems, suggests a function in maize root development via the RUM1-dependent auxin signalling pathway. PMID:25911745

  3. Application of digital image analysis for size distribution measurements of microbubbles

    Microsoft Academic Search

    S. E. Burns; S. Yiacoumi; D. Frost; C. Tsouris

    1997-01-01

    This work employs digital image analysis to measure the size distribution of microbubbles generated by the process of electroflotation for use in solid\\/liquid separation processes. Microbubbles are used for separations in the mineral processing industry and also in the treatment of potable water and wastewater.As the bubbles move upward in a solid\\/liquid column due to buoyancy, particles collide with and

  4. INTRODUCTION AUX SYSTMES INFORMATIQUES

    E-print Network

    Mignotte, Max

    de Précision ! 6 #12; REPRÉSENTATION FLOTTANTE ARITHMÉTIQUE EN FLOTTANT Multiplication & Division . . . . . . . . . . . . . . . . . . . 6 IEEE 754 Standard . . . . . . . . . . . . . . . . . . . . . . . . 8 Packed Decimal Format

  5. Les rgimes de temps: Applications l'tude du climat l'chelle rgionale

    E-print Network

    Les régimes de temps: Applications à l'étude du climat à l'échelle régionale Emilia Sanchez Gomez présentation: 1.Les régimes de temps 2.Lien entre les régimes de temps et le climat à l'échelle régionale 3.Applications: réponse de l'atmosphère aux forçages des SSTs et GHGs 4.Conclusions #12;1.Les régimes de temps

  6. Application of the polynomial chaos expansion to multiphase CFD : a study of rising bubbles and slug flow

    E-print Network

    Langewisch, Dustin R

    2014-01-01

    Part I of this thesis considers subcooled nucleate boiling on the microscale, focusing on the analysis of heat transfer near the Three-Phase (solid, liquid, and vapor) contact Line (TPL) region. A detailed derivation of ...

  7. Ordered BaAl4- Type Variants in the BaAuxSn4-x System: A Unified View on Their Phase Stabilities versus Valence Electron Counts

    SciTech Connect

    Lin, Qisheng [Ames Laboratory; Miller, Gordon J. [Ames Laboratory; Corbett, John D. [Ames Laboratory

    2014-05-28

    Three ordered structures of the tetragonal BaAl4 type were identified in the Ba–Au–Sn system, from which a unified view of the interplay between the valence electron counts (VECs) and phase stabilities of these three types of derivatives can be developed. The BaNiSn3 (I4mm), ThCr2Si2 (I4/mmm), and CaBe2Ge2 (P4/nmm) type BaAuxSn4–x phases occurred respectively at x = 0.78(1)–1, 1.38(1)–1.47(1), and 1.52(1)–2.17(1), consistent with theoretical atomic “coloring” analyses that reveal an optimal VEC of 14 for the ThCr2Si2 type but larger and smaller values respectively for the BaNiSn3- and CaBe2Ge2-type structures.

  8. Approche dynamique du premier harmonique pour la modélisation de convertisseurs AC-AC à étage intermédiaire continu. Application aux générateurs à induction

    Microsoft Academic Search

    S. Bacha; J. P. Rognon; J. P. Ferrieux; M. L. Bendaas

    1995-01-01

    In this paper, we present a modelling technique for power electronics converters with both DC and AC stages. This technique is based on a dynamical approach of the first harmonic method. The approach is first applied to an idealized converter and second is extended to a framework working under discontinuous conduction mode. At the end, comparative simulations are done to

  9. Approche dynamique du premier harmonique pour la modélisation de convertisseurs AC-AC à étage intermédiaire continu. Application aux générateurs à induction

    NASA Astrophysics Data System (ADS)

    Bacha, S.; Rognon, J. P.; Ferrieux, J. P.; Bendaas, M. L.

    1995-02-01

    In this paper, we present a modelling technique for power electronics converters with both DC and AC stages. This technique is based on a dynamical approach of the first harmonic method. The approach is first applied to an idealized converter and second is extended to a framework working under discontinuous conduction mode. At the end, comparative simulations are done to validate the continuous built model. Dans cet article, il est présenté une technique de modélisation de convertisseurs présentant à la fois des étages continus et alternatifs. Cette technique est basée sur une approche dynamique de la méthode du premier harmonique. La technique est tout d'abord appliquée à un convertisseur idéalisé pour être ensuite étendue à une structure travaillant en conclusion discontinue. En dernier lieu, des simulations viennent valider le modèle continu mis au point.

  10. Etude analytique et numérique de la réponse en vibration à hautes fréquences d'éprouvettes de fatigue vibratoire des métaux. Application aux aciers

    NASA Astrophysics Data System (ADS)

    Ben Aich, A.; El Kihel, B.; Kifani, A.; Sahban, F.

    1994-07-01

    In the present paper, the so-called " ultrasonic fatigue " or fatigue at very high frequency has been studied in the materials elastic behaviour case while neglecting the thermal effects that influence the mechanical fields. The determination of mechanical fields and specimen resonance length has been done both analytically and numerically. The numerical method used for this calculation is the finite element method (FEM). Martensitic steel " Soleil A2 " and austenitic steel " ICL 472 BC " have been considered in order to compare the two methods (analytical and numerical). It is shown that a perfect convergence is obtained between the two solutions. Dans le présent travail, la fatigue vibratoire a été étudiée dans le cas du comportement élastique des matériaux en négligeant les effets thermiques pouvant influencer les champs mécaniques. La détermination de ces champs et de la longueur de résonance des éprouvettes de fatigue a été faite analytiquement et numériquement. Le calcul numérique effectué se base sur la méthode des éléments finis. Dans le but d'une comparaison des solutions analytiques et numériques, deux aciers ont été considérés : un acier martensitique (Soleil A2) et un acier austénitique de type 18-10 (ICL 472 BC). Une parfaite convergence est obtenue entre les deux solutions.

  11. Interaction of indigo carmine dye with silica modified with humic acids at solid/liquid interface

    NASA Astrophysics Data System (ADS)

    Prado, Alexandre G. S.; Miranda, Bárbara S.; Jacintho, Guilherme V. M.

    2003-09-01

    Two distinct humic acids, one extracted from Brazilian peat soil, HA PS, and another one obtained from commercial source, HA FL, were attachment onto silica gel modified with aminopropyltrimethoxysilane, producing two material named SiHA PS and SiHA FL, respectively. The ability of these materials in removing indigo carmine dye from aqueous solution was followed through series of adsorption isotherms adjusted to modified Langmuir equation. The maximum number of moles adsorbed gave 6.82 ± 0.12 × 10 -4 and 2.15 ± 0.17 × 10 -4 mol g -1 for SiHA PS and SiHA FL, respectively. Same interactions were calorimetrically followed and the thermodynamic data showed endothermic enthalpic values: 12.31 ± 0.55 and 24.69 ± 1.05 kJ mol -1 for SiHA PS and SiHA FL surfaces, respectively. Gibbs free energies for two adsorption processes of indigo carmine dye presented negative values, reflecting dye/surface interactions must be accompanied by an increased in entropy values, which are 65 ± 3 and 98 ± 5 J mol -1 K -1 for SiHA PS and SiHA FL materials, respectively. The adsorption processes for both materials were spontaneous in nature although they presented an endothermic enthalpy for the interaction, resulting in an entropically favored process.

  12. Solid–Liquid Transitions and Stability of HPKO-in-Water Systems Emulsified by Dairy Proteins

    Microsoft Academic Search

    Leonardo Cornacchia; Yrjö H. Roos

    2011-01-01

    Stability of oil-in-water emulsions during freezing and thawing is regulated by the phase transitions occurring in the continuous\\u000a and dispersed phases upon thermal treatments and by the composition of the interfacial membrane. In the present study, the\\u000a impact of the water phase formulation (0–2.5–5–10–20–30–40% w\\/w sucrose), the interfacial composition [whey protein isolates (WPI) or sodium caseinate (NaCas) used at different

  13. Molecular Dynamics Simulation of Argon in Solid-Liquid Phase Transition Region

    Microsoft Academic Search

    Soner Özgen; Veysel Kuzucu; Osman Adigüzel

    1997-01-01

    The microstructure of 256 argon atoms located on ideal fcc lattice sites on which periodic boundary conditions have been applied at the vicinity of transition temperature has been investigated. The forces among atoms have been derived from Lennard-Jones potential energy function and the equations of motion of the system have been solved by using the Verlet algorithm. The variations in

  14. Estimation of solid-liquid ratios in bulk fats and emulsions by pulsed nuclear magnetic resonance

    Microsoft Academic Search

    M. A. J. S. van Boekel

    1981-01-01

    Several pulsed nuclear magnetic resonance (NMR) methods were evaluated to estimate the solid fat content of fats and oil-in-water\\u000a emulsions. The methods were checked with samples of paraffin oil or triolein containing known quantities of crystalline tristearate.\\u000a A method based on the signal of solid fat (with use of a correction factor, the “f-factor”) was rejected in this work for

  15. Stratification pattern in inverse binary–solid liquid–fluidized beds

    Microsoft Academic Search

    Mohammad Asif

    2010-01-01

    The inverse fluidization of unequal solid species of a binary-pair leads to the occurrence of their stratification along the height of the bed. This phenomenon depends upon the difference in the physical properties and the relative composition of the individual species comprising the binary-pair besides the fluid velocity. Packing models are used here to account for the observed volume-contraction owing

  16. Solid-liquid separation of dairy manure with PAM and chitosan polymers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic polymers are useful to increase separation of suspended solids and carbon compounds from liquid swine manure, but experiences with dairy manure are limited. In this experiment, two polymers, a synthetic polyacrylamide (PAM) and a natural chitosan were used to increase separation of suspended...

  17. Thermal modeling with solid/liquid phase change of the thermal energy storage experiment

    SciTech Connect

    Skarda, J.L.

    1991-11-01

    A thermal model which simulates combined conduction and phase change characteristics of thermal energy storage (TES) materials is presented. Both the model and results are presented for the purpose of benchmarking the conduction and phase change capabilities of recently developed and unvalidated microgravity TES computer programs. Specifically, operation of TES-1 is simulated. A two-dimensional SINDA85 model of the TES experiment in cylindrical coordinates was constructed. The phase change model accounts for latent heat stored in, or released from, a node undergoing melting and freezing.

  18. Thermal modeling with solid\\/liquid phase change of the thermal energy storage experiment

    Microsoft Academic Search

    J. Raymond Lee Skarda

    1991-01-01

    A thermal model which simulates combined conduction and phase change characteristics of thermal energy storage (TES) materials is presented. Both the model and results are presented for the purpose of benchmarking the conduction and phase change capabilities of recently developed and unvalidated microgravity TES computer programs. Specifically, operation of TES-1 is simulated. A two-dimensional SINDA85 model of the TES experiment

  19. Using Peltier cells to study solid liquid vapour transitions and supercooling

    NASA Astrophysics Data System (ADS)

    Torzo, Giacomo; Soletta, Isabella; Branca, Mario

    2007-05-01

    We propose an apparatus for teaching experimental thermodynamics in undergraduate introductory courses, using thermoelectric modules and a real-time data acquisition system. The device may be made at low cost, still providing an easy approach to the investigation of liquid solid and liquid vapour phase transitions and of metastable states (supercooling). The thermoelectric module (a technological evolution of the thermocouple) is by itself an interesting subject that offers a clear example of both thermo-electric (Seebeck effect) and electro-thermal (Peltier effect) energy transformation. We report here some cooling/heating measurements for several liquids and mixtures, including water, salt/water, ethanol/water and sodium acetate, showing how to evaluate the phenomena of freezing point depression and elevation, and how to evaluate the water latent heat.

  20. Physical Characterization of Solid-Liquid Slurries at High Weight Fractions Using Optical and Ultrasonic Methods

    SciTech Connect

    Burgess, L. W.; Brodsky, A. M.; Panetta, P. D.; Pappas, R. A.; Ahmed, S.; Tucker, B.

    2004-06-15

    The goal of this proposed work is to directly address the need for rapid on-line characterization of the physical properties of HLW slurries during all phases of the remediation process, from in-tank characterization of sediments to monitoring of the concentration, particle size, and degree of agglomeration and gelation of slurries during transport. Current technologies are not capable of characterizing the HLW waste stream without dilution. The results from this work will be utilized to develop new methodologies to characterize the HLW stream in-situ. There are three tasks: (1) develop new optical and acoustic scattering measurements to provide the fundamental science needed for successful device development and implementation, (2) develop theories that describe the interrelationship between wave propagation and the physical properties of the slurry, and (3) perform inversions of the theories and compare them with the experimental measurements to non-intrusively characterize slurries.

  1. Physical Characterization of Solid-Liquid Slurries at High Weight Fractions Utilizing Optical and Ultrasonic Methods

    SciTech Connect

    Burgess, Lloyd W.

    2005-06-01

    The goal of this proposed work is to directly address the need for rapid on-line characterization of the physical properties of HLW slurries during all phases of the remediation process, from in-tank characterization of sediments to monitoring of the concentration, particle size, and degree of agglomeration and gelation of slurries during transport. There are three tasks: (1) develop new optical and acoustic scattering measurements to provide the fundamental science needed for successful device development and implementation, (2) develop theories that describe the interrelationship between wave propagation and the physical properties of the slurry, and (3) perform inversions of the theories and compare them with the experimental measurements to non-intrusively characterize slurries.

  2. Physical Characterization of Solid-Liquid Slurries at High Weight Fractions Using Optical and Ultrasonic Methods

    SciTech Connect

    Burgess, L. W.; Brodsky, A. M.; Panetta, P. D.; Pappas, R. A.; Bond, L. J.; Bamberger, J. A.

    2002-05-28

    The goal of this proposed work is to directly address the need for rapid on-line characterization of the physical properties of HLW slurries during all phases of the remediation process, from in-tank characterization of sediments to monitoring of the concentration, particle size, and degree of agglomeration and gelation of slurries during transport. This will be done with both optical and ultrasonic methods. There are three tasks: (1) develop optical and acoustic measurements to provide the fundamental science needed for successful device development and implementation, (2) develop theories that describe the interrelationship between wave propagation and the physical properties of the slurry, and (3) solve, in the framework of these theories, the inversion problem and compare them with the experimental measurements to non-intrusively characterize slurries.

  3. Depletion at Solid-Liquid Interfaces under Shear: Flowing Hexadecane on Functionalized Surfaces

    SciTech Connect

    Guttfreund, Philipp [Ruhr University, Bochum, Germany; Wolff, Max [Uppsala University, Uppsala, Sweden; Maccarini, Marco [Institut Laue-Langevin (ILL); Gerth, Stefan [Universitat Erlangen, Germany; Ankner, John Francis [ORNL; Browning, Jim [ORNL; Halbert, Candice E [ORNL; Wacklin, Hanna [Institut Laue-Langevin (ILL); Zabel, Hartmut [Ruhr University, Bochum, Germany

    2011-01-01

    We present a neutron reflectivity study on the interface of flowing hexadecane, which is known to exhibit surface slip on functionalized solid surfaces. The single crystalline silicon substrates are either chemically cleaned or covered by octadecyl-trichlorosilane (OTS) which result in different interfacial energies in respect to hexadecane. The liquid is in situ sheared and the reflectivities are compared to the static case. Moreover, the temperature dependence is recorded. For both types of interface, density depleted layers are observed, but shear affects them differently. Whereas at the attractive surface the depletion is enhanced by shear, the low interfacial energy leads to a diminishment of the depleted layer when applying shear. This systematic change of the depletion layer indicates different structural rearrangements under shear load. Finally, the possible link of the depletion layer with surface slip is discussed.

  4. Solids-liquid separation of swine manure with polymer treatment and sand filtration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Small particles typical of liquid swine manure often clog sand filter beds and fine filters. We evaluated the effectiveness of polymer flocculants to improve drainage and filtration performance of sand filter beds by increasing the effective particle size. A pilot unit was evaluated at the Swine U...

  5. Selective Solid-Liquid Extraction of Lithium Halide Salts Using a Ditopic Macrobicyclic Receptor

    E-print Network

    Smith, Bradley D.

    is strongly affected by the properties of the extracted counteranion. For example, a competitive anion properties of ditopic salt receptor 1 (Chart 1). Previously, we have reported that compound 1 has. Fax: 574 631 6652. (1) (a) Principles and Practices of SolVent Extraction; Rydberg, J., Nusikas, C

  6. Study on effect of microparticle's size on cavitation erosion in solid-liquid system

    NASA Astrophysics Data System (ADS)

    Chen, Haosheng; Liu, Shihan; Wang, Jiadao; Chen, Darong

    2007-05-01

    Five different solutions containing microparticles in different sizes were tested in a vibration cavitation erosion experiment. After the experiment, the number of erosion pits on sample surfaces, free radicals HO• in solutions, and mass loss all show that the cavitation erosion strength is strongly related to the particle size, and 500nm particles cause more severe cavitation erosion than other smaller or larger particles do. A model is presented to explain such result considering both nucleation and bubble-particle collision effects. Particle of a proper size will increase the number of heterogeneous nucleation and at the same time reduce the number of bubble-particle combinations, which results in more free bubbles in the solution to generate stronger cavitation erosion.

  7. ELECTRON TRANSFER MECHANISM AT THE SOLID-LIQUID INTERFACE OF PHYLLOSILICATES

    EPA Science Inventory

    Interfacial electron transfer processes on clay minerals have significant impact in natural environments and geochemical systems. Nitrobenzene was used as molecular probes to study the electron transfer mechanism at the solid-water interfaces of Fe-containing phyllosicates. For...

  8. Experimental investigation of solid–liquid mixtures freezing behavior in flow channels

    Microsoft Academic Search

    Yu Hasegawa; Shunichi Seo; Yusuke Himuro; Koji Morita; Tatsuya Matsumoto; Kenji Fukuda; Werner Maschek

    2011-01-01

    The penetration and freezing of hot-core material mixtures through flow channels during core disruptive accidents (CDAs) within a sodium-cooled fast reactor is one of the major concerns confronting safety designers of the next-generation reactors. The main objective of this study is to investigate those fundamental characteristics of penetration and solidification involved in channeling molten metal and solid particle mixtures over

  9. Solid-liquid contacting in industrial crystallizers and its influence on product size distribution

    Microsoft Academic Search

    P. A. M. Grootscholten

    1982-01-01

    The population balance concept, nucleation kinetics, growth and dissolution of sodium chloride crystals, a pilot plant crystallizer with double radial inlet are discussed, and the effect of crystallizer geometry on crystallizer performance.

  10. n-CuInSe2 photoelectrochemical cells - Solid state or solid-liquid junctions?

    NASA Astrophysics Data System (ADS)

    Cahen, David; Tomkiewicz, Micha; Shen, Wu-Mian; Matson, R. J.

    In order to determine whether n-CuInSe2 photoelectrochemical cells are semiconductor/liquid electrolyte or solid state solar cells, data from impedance measurements on electrochemical and solid state devices, and from EBIC measurements on solid state devices are analyzed. A small barrier is found which is insufficient to account for the observed V(oc) with an electrolyte. It is suggested that these cells act as semiconductor/liquid electrolyte cells with air oxidation leading to decreased recombination losses by increasing the depletion layer width.

  11. Solid-liquid interfaces of ionic liquid solutions-Interfacial layering and bulk correlations.

    PubMed

    Mezger, Markus; Roth, Roland; Schröder, Heiko; Reichert, Peter; Pontoni, Diego; Reichert, Harald

    2015-04-28

    The influence of the polar, aprotic solvent propylene carbonate on the interfacial structure of the ionic liquid (IL) 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate on sapphire was investigated by high-energy x-ray reflectivity. Experiments at solvent concentrations between 17 mol. % and 83 mol. % bridge the gap between diluted electrolytes described by the classical Gouy-Chapman theory and pure ionic liquids. Analysis of our experimental data revealed interfacial profiles comprised of alternating anion and cation enriched regions decaying gradually into the bulk liquid. With increasing solvent concentration, we observed a decrease in correlation length of the interfacial layering structure. At high ion concentrations, solvent molecules were found to accumulate laterally within the layers. By separating like-charged ions, they reduce their Coulomb repulsion. The results are compared with the bulk structure of IL/solvent blends probed by x-ray scattering and predictions from fundamental fluid theory. PMID:25933784

  12. SESAME 96170, a solid-liquid equation of state for CeO2

    SciTech Connect

    Chisolm, Eric D. [Los Alamos National Laboratory] [Los Alamos National Laboratory

    2014-05-02

    I describe an equation of state (EOS) for the low-pressure solid phase and liquid phase of cerium (IV) oxide, CeO{sub 2}. The models and parameters used to calculate the EOS are presented in detail, and I compare with data for the full-density crystal. Hugoniot data are available only for high-porosity powders, and I discuss difficulties in comparing with such data. I have constructed SESAME 96170, an EOS for cerium (IV) oxide that includes the ambient solid and liquid phases. The EOS extends over the full standard SESAME range, but should not be used at low temperatures and high densities because of the lack of a high-pressure solid phase. I have described the models used to compute the three terms of the EOS (cold curve, nuclear, and thermal electronic), and I have given the parameters used in the models. They were determined by comparison with experimental data at P = 1 atm, including the constant-pressure specific heat, coefficient of thermal expansion, and melting and boiling points. The EOS compares well with data in its intended range of validity, but the presence of high-frequency optical modes in its phonon spectrum limits the agreement of our models with thermal data. The next step is to construct a multiphase EOS that includes the low- and high-pressure solid phases and the liquid. The DAC data from Duclos will most strongly constrain the parameters of the high-pressure solid. A remaining issue is the comparison of the crystal-density EOS with experimental Hugoniot data, which are taken at much lower initial data because the samples are porous powders. A satisfactory means of modeling porosity, allowing comparison of theory and experiment, has not yet been produced.

  13. Computer simulation and design of gravity solid-liquid separation units

    Microsoft Academic Search

    D. C. Elmore; L. K. Wang

    1981-01-01

    Two computer programs are presented that perform all the necessary calculations when the process being considered involves the clarification of a fluid, namely, water. The first computer program handles class 1 sedimentation which is the clarification of a fluid containin a dilute suspension of nonflocculating particls. The second computer program handles class 2 sedimentation which is the clarification of a

  14. To appear in ACM Transactions on Graphics Simulating Liquids and Solid-Liquid Interactions with

    E-print Network

    O'Brien, James F.

    , and Pixar. Correspondence author: J. F. O'Brien, University of California, Berkeley, CA; email: job with Lagrangian Meshes Pascal Clausen, Martin Wicke, Jonathan R. Shewchuk, and James F. O'Brien University the dynamic tetrahedral simulation mesh. ACM Reference Format: Clausen, P., Wicke, M., Shewchuk, J. R., and O

  15. Quartz Crystal Microbalance Studies of Multilayer Glucagon Fibrillation at the Solid-Liquid Interface

    PubMed Central

    Hovgaard, Mads Bruun; Dong, Mingdong; Otzen, Daniel Erik; Besenbacher, Flemming

    2007-01-01

    We have used a quartz crystal microbalance with dissipation (QCM-D) to monitor the changes in layer thickness and viscoelastic properties accompanying multilayer amyloid deposition in situ for the first time. By means of atomic force microscope imaging, an unequivocal correlation is established between the interfacial nucleation and growth of glucagon fibrils and the QCM-D response. The combination of the two techniques allows us to study the temporal evolution of the interfacial fibrillation process. We have modeled the QCM-D data using an extension to the Kelvin-Voigt viscoelastic model. Three phases were observed in the fibrillation process: 1), a rigid multilayer of glucagon monomers forms and slowly rearranges; 2), this multilayer subsequently evolves into a dramatically more viscoelastic layer, containing a polymorphic network of micrometer-long fibrils growing from multiple nucleation sites; and 3), the fibrillar formation effectively stops as a result of the depletion of bulk-phase monomers, although the process can be continued without a lag phase by subsequent addition of fresh monomers. The robustness of the QCM-D technique, consolidated by complementary atomic force microscope studies, should make it possible to combine different components thought to be involved in the plaque formation process and thus build up realistic models of amyloid plaque formation in vitro. PMID:17513349

  16. Perturbation theory of solid-liquid interfacial free energies of bcc metals

    SciTech Connect

    Zhang, Lei; Koschny, Thomas; Soukoulis, Costas M.

    2012-01-18

    We present an experimental and numerical study of the transmission of a photonic crystal perforated by two subwavelength slits, separated by two wavelengths.The experimental near-field image of the double-slit design of the photonic crystal shows an interference pattern, which is analogous to Young’s experiment. This interference arises as a consequence of the excitation of surface states of the photonic crystals and agrees very well with the simulations.

  17. Melting Temperature of Ice Ih calculated from coexisting solid-liquid phases

    SciTech Connect

    Wang, J. [University of Nebraska, Lincoln; Yoo, S. [University of Nebraska, Lincoln; Bai, J. [University of Nebraska, Lincoln; Morris, James R [ORNL; Zeng, X.C. [University of Nebraska, Lincoln

    2005-01-01

    In a previous paper we report the calculated melting temperature of the proton-disordered hexagonal ice I{sub h} using a four-site water model, the TIP4P (Ref. 2) and a five-site model, the TIP5P. In that work, we used a free-energy method. For the TIP4P model, the calculated melting temperature at 1 bar is T{sub m} = 229 {+-} 9 K, whereas for the TIP5P model, T{sub m} = 268 {+-} 6 K. For both models, the long-ranged interactions were truncated at 17 {angstrom}. Interestingly, these values of Tm are very close to T{sub m} = 232 {+-} 5 K and T{sub m} = 273.9 K reported by Sanz et al. and Vega et al. who used a slightly different free-energy method along with Ewald summation technique, although both the TIP4P and TIP5P models were originally developed for use with a truncated Coulomb interaction. The purpose of this paper is twofold: (1) to compute the melting temperature (T{sub m}) of ice I{sub h} with both TIP4P and TIP5P models by using the two-phase coexistence method and to compare with previously obtained T{sub m}; (2) to compute the T{sub m} using recently improved TIP4P and TIP5P models, namely, the TIP4P-Ew (Ref. 6) and TIP5P-Ew (Ref. 7) models. Both models are developed specifically for use with Ewald techniques. The TIP4P-Ew model, in particular, has shown substantial improvement over the original TIP4P model as it can reproduce the density maximum at about 274 K, very close to 277 K of the real water. The original TIP5P model can reproduce the measured T{sub m}. It will be of interest to see whether the improved TIP5P-Ew model can still hold the same level of prediction as far as the T{sub m} is concerned.

  18. Solid-liquid interfaces of ionic liquid solutions—Interfacial layering and bulk correlations

    NASA Astrophysics Data System (ADS)

    Mezger, Markus; Roth, Roland; Schröder, Heiko; Reichert, Peter; Pontoni, Diego; Reichert, Harald

    2015-04-01

    The influence of the polar, aprotic solvent propylene carbonate on the interfacial structure of the ionic liquid (IL) 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate on sapphire was investigated by high-energy x-ray reflectivity. Experiments at solvent concentrations between 17 mol. % and 83 mol. % bridge the gap between diluted electrolytes described by the classical Gouy-Chapman theory and pure ionic liquids. Analysis of our experimental data revealed interfacial profiles comprised of alternating anion and cation enriched regions decaying gradually into the bulk liquid. With increasing solvent concentration, we observed a decrease in correlation length of the interfacial layering structure. At high ion concentrations, solvent molecules were found to accumulate laterally within the layers. By separating like-charged ions, they reduce their Coulomb repulsion. The results are compared with the bulk structure of IL/solvent blends probed by x-ray scattering and predictions from fundamental fluid theory.

  19. An experimental measurement of the thermal conductivity and diffusivity of a porous solid-liquid system 

    E-print Network

    Dunn, James Elliott

    1959-01-01

    ~ kerosene, and air occupying the pore space of the sandstone. The principal variable studied in this series oi' tests was number A-2-a in the preceding outline~ that is the effect of relative amounts of the three fluids water, kerosene~ and air...~ deaereated 22 1. 0 O. e 1 2 0. 2 0. 0 Hinutes 16 THE RELATI/N OF TLNPERATVRE CIWGE FBACTION, ~n, WITH TINE FOB H - i SANDSTONE BATUBATND WITH 1. Ninety-Eight Psr cent Water 2. Ninety~ght Per cent Kerosene 3. Air At Atnospheric Pressuxe 4. Air...

  20. SOLID-LIQUID SEPARATION OF SWINE MANURE WITH POLYMER TREATMENT AND SAND FILTRATION

    Microsoft Academic Search

    M. B. Vanotti; J. M. Rice; A. Q. Ellison; P. G. Hunt; F. J. Humenik; C. L. Baird

    Small particles typical of liquid swine manure often clog sand filter beds and fine filters. We evaluated the effec- tiveness of polymer flocculants to improve drainage and filtration performance of sand filter beds by increasing the particle size of manure. A pilot separation unit was evaluated at the Swine Unit of the NCSU Lake Wheeler Road Laboratory in Ra- leigh,

  1. Multiscale Engineering of solid-liquid interfaces Wednesday October 27, 2010, Babbio 122, 10am

    E-print Network

    Fisher, Frank

    him five grants as a PI, including the NSF CAREER award for young investigators. Since February 2010 University. He has produced 25 journal articles, 40 conference papers, 2 book chapters, and 2 edited books, he has received awards for more than one million $US as a primary investigator, from NSF and the US

  2. Elucidating the solid, liquid and gaseous products from batch pyrolysis of cotton-gin trash. 

    E-print Network

    Aquino, Froilan Ludana

    2009-05-15

    Cotton-gin trash (CGT) was pyrolyzed at different temperatures and reaction times using an externally-heated batch reactor. The average yields of output products (solid/char, liquid/bio-oil, and gaseous) were determined. ...

  3. Phase-field Models for Solidification and Solid/Liquid Interactions 

    E-print Network

    Park, Min Soo

    2011-02-22

    The microstructure resulting from the solidification of alloys can greatly affect their properties, making the prediction of solidification phenomena under arbitrary conditions a very important tool in the field of ...

  4. Water-induced correlation between single ions imaged at the solid-liquid interface

    NASA Astrophysics Data System (ADS)

    Ricci, Maria; Spijker, Peter; Voïtchovsky, Kislon

    2014-07-01

    When immersed into water, most solids develop a surface charge, which is neutralized by an accumulation of dissolved counterions at the interface. Although the density distribution of counterions perpendicular to the interface obeys well-established theories, little is known about counterions’ lateral organization at the surface of the solid. Here we show, by using atomic force microscopy and computer simulations, that single hydrated metal ions can spontaneously form ordered structures at the surface of homogeneous solids in aqueous solutions. The structures are laterally stabilized only by water molecules with no need for specific interactions between the surface and the ions. The mechanism, studied here for several systems, is controlled by the hydration landscape of both the surface and the adsorbed ions. The existence of discrete ion domains could play an important role in interfacial phenomena such as charge transfer, crystal growth, nanoscale self-assembly and colloidal stability.

  5. Potential of solid-liquid separation of swine wastes for methane production

    SciTech Connect

    Holmberg, R.D.; Hill, D.T.; Prince, T.J.; Van Dyke, N.J.

    1983-01-01

    The feasibility of using a vibrating screen separator to concentrate flushed swine waste for use in an anaerobic digestor system is evaluated on the basis of the properties of the solid separator Four flowrates (37.5, 75, 112.5, and 150 L/min) and five screen mesh sizes (8,18, 30, 60, and 150) were combined for trial runs on a 45.7 cum diameter Sweco vibrating separator. The waste was obtained from a finishing house flushing waste disposal system. Analysis of the flushed waste, and the liquid and solid separate included total solids (TS), volatile solids (VS), fixed solids (FS), total carbon (TC), chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN-N), ammonia (NH3-N), total (TP-P) and orthophosphate (OP-P). Mass balances calculated from the results of the different combinations of flowrate and screen size in the continuous flow system showed that the total amount of organic material (measured as volatile solids) retained on the screens varied from 17 to 70%, TKN-N varied from 2.5 to 50%, NH3-N from 3 to 47%, and ortho-phosphate from 9 to 57% with increasing screen mesh and flowrate. (Refs. 11).

  6. Theory of Brushes Formed by ?-Shaped Macromolecules at Solid-Liquid Interfaces.

    PubMed

    Zhulina, Ekaterina B; Leermakers, Frans A M; Borisov, Oleg V

    2015-06-16

    We present a theoretical analysis targeted to describe the structural properties of brushes formed by ?-shaped macromolecules tethered by terminal segment of stem to planar surface while exposing multiple free branches to the surrounding solution. We use an analytical self-consistent field approach based on the strong stretching approximation, and the assumption of Gaussian elasticity for linear chain fragments of the tethered macromolecules. The effect of weak and strong polydispersity of branches is analyzed. In the case of weakly polydisperse macromolecules, variations in length of branches lead to a more uniform polymer density distribution with slight increase in the brush thickness compared to the case of monodisperse chains with the same degree of polymerization. We demonstrate that in contrast to linear chains, strong polydispersity of ?-shaped macromolecules does not necessarily lead to strong perturbations in polymer density distribution. In particular, mixed brushes of the so-called "mirror" dendrons (in which number of stem monomers in one component coincides with number of monomers in a branch of the other component, and vice versa) give rise to a unified polymer density distribution with shape independent of the brush composition. The predictions of analytical theory are systematically compared to the results of numerical self-consistent field modeling based on the Scheutjens-Fleer approach. PMID:26029884

  7. Self-mobility of flexible polymers adsorbed at a solid-liquid interface

    Microsoft Academic Search

    R. Varoqui; E. Pefferkorn

    In the present paper, we report on the rate of exchange of 3H-labelled polymers in the adsorbed state with non-labelled polymers in the solution. The method consisted in carrying out\\u000a preliminary adsorption with radioactive polymers, and subsequently exposing the surface to a solution of non-labelled polymers,\\u000a and in continuously analyzing the radioactivity of the solution. in that way, chemical composition

  8. Elucidating the solid, liquid and gaseous products from batch pyrolysis of cotton-gin trash.

    E-print Network

    Aquino, Froilan Ludana

    2009-05-15

    Cotton-gin trash (CGT) was pyrolyzed at different temperatures and reaction times using an externally-heated batch reactor. The average yields of output products (solid/char, liquid/bio-oil, and gaseous) were determined. The heating value (HV...

  9. Thermal modeling with solid/liquid phase change of the thermal energy storage experiment

    NASA Technical Reports Server (NTRS)

    Skarda, J. Raymond Lee

    1991-01-01

    A thermal model which simulates combined conduction and phase change characteristics of thermal energy storage (TES) materials is presented. Both the model and results are presented for the purpose of benchmarking the conduction and phase change capabilities of recently developed and unvalidated microgravity TES computer programs. Specifically, operation of TES-1 is simulated. A two-dimensional SINDA85 model of the TES experiment in cylindrical coordinates was constructed. The phase change model accounts for latent heat stored in, or released from, a node undergoing melting and freezing.

  10. SESAME 96170, a solid-liquid equation of state for CeO2

    Microsoft Academic Search

    Chisolm; Eric D

    2012-01-01

    I describe an equation of state (EOS) for the low-pressure solid phase and liquid phase of cerium (IV) oxide, CeOâ. The models and parameters used to calculate the EOS are presented in detail, and I compare with data for the full-density crystal. Hugoniot data are available only for high-porosity powders, and I discuss difficulties in comparing with such data. I

  11. From colloidal dispersions to colloidal pastes through solid/liquid separation processes

    E-print Network

    Paris-Sud XI, Université de

    of industrial processes, including drying, slip casting, pressure filtration, and centrifugation (Table I to thermodynamic processes where pressure is applied to a system in order to reduce its volume. In dispersions generates large osmotic pressures; these pressures may be calculated, through the cell model, as the cost

  12. ADSORPTION OF SURFACTANTS AND POLYMERS AT THE SOLID-LIQUID INTERFACE. (R823301)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  13. Mathematics and Mechanics of Solids (to appear) Mathematical Modelling of a SolidLiquid

    E-print Network

    Ambrosi, Davide

    " (stress­free states) corresponding, in a certain sense, to the growth stages. The response of the solid stress ten- sor. An example of a possible choice of the constitutive functions is also presented. Key other contexts such as magma mechanics, paper pulp rolling, fabric dying and drying, coffee brewing

  14. Molecular structure and equilibrium forces of bovine submaxillary mucin adsorbed at a solid-liquid interface.

    PubMed

    Zappone, Bruno; Patil, Navinkumar J; Madsen, Jan B; Pakkanen, Kirsi I; Lee, Seunghwan

    2015-04-21

    By combining dynamic light scattering, circular dichroism spectroscopy, atomic force microscopy, and surface force apparatus, the conformation of bovine submaxillary mucin in dilute solution and nanomechanical properties of mucin layers adsorbed on mica have been investigated. The samples were prepared by additional chromatographic purification of commercially available products. The mucin molecule was found to have a z-average hydrodynamic diameter of ca. 35 nm in phosphate buffered solution, without any particular secondary or tertiary structure. The contour length of the mucin is larger than, yet of the same order of magnitude as the diameter, indicating that the molecule can be modeled as a relatively rigid polymeric chain due to the large persistence length of the central glycosylated domain. Mucin molecules adsorbed abundantly onto mica from saline buffer, generating polymer-like, long-ranged, repulsive, and nonhysteretic forces upon compression of the adsorbed layers. Detailed analysis of such forces suggests that adsorbed mucins had an elongated conformation favored by the stiffness of the central domain. Acidification of aqueous media was chosen as means to reduce mucin-mucin and mucin-substrate electrostatic interactions. The hydrodynamic diameter in solution did not significantly change when the pH was lowered, showing that the large persistence length of the mucin molecule is due to steric hindrance between sugar chains, rather than electrostatic interactions. Remarkably, the force generated by an adsorbed layer with a fixed surface coverage also remained unaltered upon acidification. This observation can be linked to the surface-protective, pH-resistant role of bovine submaxillary mucin in the variable environmental conditions of the oral cavity. PMID:25806669

  15. A unified correlation for estimating HHV of solid, liquid and gaseous fuels

    Microsoft Academic Search

    S. A. Channiwala; P. P. Parikh

    2002-01-01

    A unified correlation for computation of higher heating value (HHV) from elemental analysis of fuels is proposed in this paper. This correlation has been derived using 225 data points and validated for additional 50 data points. The entire spectrum of fuels ranging from gaseous, liquid, coals, biomass material, char to residue-derived fuels has been considered in derivation of present correlation.

  16. Solid-liquid distribution of selected concrete admixtures in hardened cement pastes

    SciTech Connect

    Glaus, Martin A. [Laboratory for Waste Management, OHLD/002, Paul Scherrer Institut, CH-5232 Villigen (Switzerland)]. E-mail: martin.glaus@psi.ch; Laube, A. [Laboratory for Waste Management, OHLD/002, Paul Scherrer Institut, CH-5232 Villigen (Switzerland); Van Loon, Luc R. [Laboratory for Waste Management, OHLD/002, Paul Scherrer Institut, CH-5232 Villigen (Switzerland)

    2006-07-01

    The distribution between hardened cement paste and cement pore water of selected concrete admixtures (BZMs), i.e., sulfonated naphthalene-formaldehyde condensate (NS), lignosulfonate (LS) and a gluconate-containing plasticiser used at the Paul Scherrer Institute for waste conditioning, was measured. Sorption data were fitted to a single-site Langmuir isotherm with affinity constants K = (19 {+-} 4) dm{sup 3} g{sup -1} for NS, K = (2.1 {+-} 0.6) dm{sup 3} g{sup -1} for LS and sorption capacities q = (81 {+-} 16) g kg{sup -1} for NS, q = (43 {+-} 8) g kg{sup -1} for LS. In the case of gluconate, a two-site Langmuir sorption model was necessary to fit the data satisfactorily. Sorption parameters for gluconate were K {sub 1} = (2 {+-} 1) x 10{sup 6} dm{sup 3} mol{sup -1} and q {sub 1} = (0.04 {+-} 0.02) mol kg{sup -1} for the stronger binding site and K {sub 2} = (2.6 {+-} 1.1) x 10{sup 3} dm{sup 3} mol{sup -1} and q {sub 2} = (0.7 {+-} 0.3) mol kg{sup -1} for the weaker binding site. Desorption of these BZMs from cement pastes and pore water in cement specimens prepared in the presence of the BZMs were then used to test the model. It was found that only minor parts of NS and LS could be mobilised as long as the cement composition was intact, whereas the sorption of gluconate was found to be reversible. The Langmuir model makes valuable predictions in the qualitative sense in that the pore water concentration of the BZMs is reduced by several orders of magnitude as compared to the initial concentrations. In view of the necessity for conservative predictions used in the safety analysis for disposal of radioactive waste, however, the predictions are unsatisfactory in that the measured pore water concentrations of NS and LS were considerably larger than the predicted values. This conclusion does not apply for gluconate, because its concentration in cement pore water was below the detection limit of {approx}50 nM.

  17. Self-similar microstructural evolution of dendritic solid?liquid mixtures during coarsening

    SciTech Connect

    Fife, J.L.; Voorhees, P.W.; (NWU)

    2009-06-12

    The microstructural evolution of equiaxed dendritic Al-Cu microstructures of two different solid volume fractions (46% and 72%) during isothermal coarsening was studied. We found that the microstructures evolved self-similarly, both morphologically and topologically, while the inverse specific surface area increased as the cube root of time. The differences in scaled morphologies and topologies could be attributed to the difference in solid volume fraction, with the higher volume fraction sample exhibiting a more compact interface shape distribution and a smaller scaled genus.

  18. Ultrasonically assisted rapid solid-liquid separation of fine clean coal particles

    Microsoft Academic Search

    B. P. Singh

    1999-01-01

    An investigation on the effects of sonic waves to improve the efficiency of fine coal dewatering in vacuum filtration has been carried out. The objective was to study the synergistic effect of vacuum filtration and sonication in the presence of surface active agents and to understand the importance of the various process parameters to devise scale up criteria for industrial

  19. Using Peltier Cells to Study Solid-Liquid-Vapour Transitions and Supercooling

    ERIC Educational Resources Information Center

    Torzo, Giacomo; Soletta, Isabella; Branca, Mario

    2007-01-01

    We propose an apparatus for teaching experimental thermodynamics in undergraduate introductory courses, using thermoelectric modules and a real-time data acquisition system. The device may be made at low cost, still providing an easy approach to the investigation of liquid-solid and liquid-vapour phase transitions and of metastable states…

  20. Quantification of ordering at a solid-liquid interface using plasmon electron energy loss spectroscopy

    NASA Astrophysics Data System (ADS)

    Gandman, Maria; Kauffmann, Yaron; Kaplan, Wayne D.

    2015-02-01

    We present an in situ electron energy loss spectroscopy (EELS) study of ordering of liquid Al at various Al-Al2O3 interfaces. This technique utilizes precise measurements of the shifts in bulk plasmon resonance and their sensitivity to the valence electron density. Plasmon EELS combined with high resolution transmission electron microscopy provides information regarding the chemical composition in liquid Al at Al-Al2O3 interfaces. Preferential oxygen segregation to the (0006) Al2O3 plane was verified, and the ( 10 1 ¯ 2 ) Al2O3 plane was found to contain the lowest amount of segregated species.

  1. GENERAL RESEARCH A Generalized Method for the Solid-Liquid Equilibrium Stage and

    E-print Network

    Zhang, Luzheng

    Processes related to aqueous electrolyte solutions and solid phases represent an important aspect of modern. For aqueous electrolyte solutions, a large number of models have been proposed, and the parameters of all of the models have been correlated with experimental data for up to saturated solutions. In other words

  2. Sigle Dpartement Gr. Titre Enseignant Jour Date Heure Local Nb Rpartition ADM502 Pharmacologie 01 Initiation aux affaires en pharmacologie Beaudoin, Philippe vendredi 03-oct 09h 11h FMSS

    E-print Network

    Vellend, Mark

    Initiation aux affaires en pharmacologie Beaudoin, Philippe vendredi 03-oct 09h à 11h FMSS ALM300 Biologie 01 Nutrition Brouillette, Suzanne mardi 21-oct 10h30 à 12h30 D7-2021 24 Bald à Lépine ALM300 Biologie 01 Nutrition Brouillette, Suzanne mardi 21-oct 10h30 à 12h30 D7-2023 20 Lévesque à Thomas BCL102 Biologie 01

  3. Le dpartement d'Etudes Slaves de l'Universit Blaise Pascal propose aux tudiants un parcours complet en tudes russes depuis la premire anne de Licence. Le cursus de russe

    E-print Network

    Sart, Remi

    · Le département d'Etudes Slaves de l'Université Blaise Pascal propose aux étudiants un parcours étudiantes ont toutes deux préparé un Master 1 d'études Russophones toujours à l'Université Blaise Pascal. L toujours à l'Université Blaise Pascal et occupe conjointement un emploi à mi-temps tandis que l

  4. Travailleurs âgés, nouvelles technologies et changements organisationnels : un réexamen à partir de l'enquête « Reponse ». Suivi d'un commentaire de Luc Behaghel : emploi des seniors - Des effets du changement technologique aux recommandations

    Microsoft Academic Search

    Patrick Aubert; Luc Behaghel; Sévane Ananian

    2006-01-01

    [fre] L'adoption par les entreprises d'innovations technologiques (micro-ordinateur, internet), de changements organisationnels ou leur ouverture au marché international posent la question de l'adaptation des travailleurs âgés (seniors) : les entreprises concernées évincent-elles plus souvent ou non les seniors de leur main-d'oeuvre ? L'analyse du stock d'emploi en 1998 confirme l'hypothèse d'un biais de ces changements défavorable aux seniors. Dans l'industrie

  5. DET/MPS - THE GSFC ENERGY BALANCE PROGRAM, DIRECT ENERGY TRANSFER/MULTIMISSION SPACECRAFT MODULAR POWER SYSTEM (MACINTOSH A/UX VERSION)

    NASA Technical Reports Server (NTRS)

    Jagielski, J. M.

    1994-01-01

    The DET/MPS programs model and simulate the Direct Energy Transfer and Multimission Spacecraft Modular Power System in order to aid both in design and in analysis of orbital energy balance. Typically, the DET power system has the solar array directly to the spacecraft bus, and the central building block of MPS is the Standard Power Regulator Unit. DET/MPS allows a minute-by-minute simulation of the power system's performance as it responds to various orbital parameters, focusing its output on solar array output and battery characteristics. While this package is limited in terms of orbital mechanics, it is sufficient to calculate eclipse and solar array data for circular or non-circular orbits. DET/MPS can be adjusted to run one or sequential orbits up to about one week, simulated time. These programs have been used on a variety of Goddard Space Flight Center spacecraft projects. DET/MPS is written in FORTRAN 77 with some VAX-type extensions. Any FORTRAN 77 compiler that includes VAX extensions should be able to compile and run the program with little or no modifications. The compiler must at least support free-form (or tab-delineated) source format and 'do do-while end-do' control structures. DET/MPS is available for three platforms: GSC-13374, for DEC VAX series computers running VMS, is available in DEC VAX Backup format on a 9-track 1600 BPI tape (standard distribution) or TK50 tape cartridge; GSC-13443, for UNIX-based computers, is available on a .25 inch streaming magnetic tape cartridge in UNIX tar format; and GSC-13444, for Macintosh computers running AU/X with either the NKR FORTRAN or AbSoft MacFORTRAN II compilers, is available on a 3.5 inch 800K Macintosh format diskette. Source code and test data are supplied. The UNIX version of DET requires 90K of main memory for execution. DET/MPS was developed in 1990. A/UX and Macintosh are registered trademarks of Apple Computer, Inc. VMS, DEC VAX and TK50 are trademarks of Digital Equipment Corporation. UNIX is a registered trademark of AT&T Bell Laboratories.

  6. Extension of the broadband single-mode integrated optical waveguide technique to the ultraviolet spectral region and its applications

    PubMed Central

    Wiederkehr, Rodrigo S.; Mendes, Sergio B.

    2014-01-01

    We report here the fabrication, characterization, and application of a single-mode integrated optical waveguide (IOW) spectrometer capable of acquiring optical absorbance spectra of surface-immobilized molecules in the visible and ultraviolet spectral region down to 315 nm. The UV-extension of the single-mode IOW technique to shorter wavelengths was made possible by our development of a low-loss single-mode dielectric waveguide in the UV region based on an alumina film grown by atomic layer deposition (ALD) over a high quality fused silica substrate, and by our design/fabrication of a broadband waveguide coupler formed by an integrated diffraction grating combined with a highly anamorphic optical beam of large numerical aperture. As an application of the developed technology, we report here the surface adsorption process of bacteriochlorophyll a on different interfaces using its Soret absorption band centred at 370 nm. The effects of different chemical compositions at the solid/liquid interface on the adsorption and spectral properties of bacteriochlorophyll a were determined from the polarized UV-Vis IOW spectra acquired with the developed instrumentation. The spectral extension of the single-mode IOW technique into the ultraviolet region is an important advance as it enables extremely sensitive studies in key characteristics of surface molecular processes (e.g., protein unfolding and solvation of aromatic amino-acid groups under surface binding) whose spectral features are mainly located at wavelengths below the visible spectrum. PMID:24466569

  7. Manufacture, characterisation and application of cellular metals and metal foams

    Microsoft Academic Search

    John Banhart

    2001-01-01

    The possibilities for manufacturing metal foams or other porous metallic structures are reviewed. The various manufacturing processes are classified according to the state of matter in which the metal is processed — solid, liquid, gaseous or ionised. Liquid metal can be foamed directly by injecting gas or gas-releasing blowing agents, or by producing supersaturated metal–gas solutions. Indirect methods include investment casting,

  8. Application of a new Raman microprobe spectrometer to nondestructive analysis of sulfate and other ions in individual phases in fluid inclusions in minerals

    USGS Publications Warehouse

    Rosasco, G.J.; Roedder, E.

    1979-01-01

    Rosasco et al. (1975), reported the first successful application of laser-excited Raman spectroscopy for the identification and nondestructive partial analysis of individual solid, liquid, and gaseous phases in selected fluid inclusions. We report here the results of the application of a new instrument, based on back-scattering, that eliminates many of the previous stringent sample limitations and hence greatly expands the range of applicability of Raman spectroscopy to fluid inclusions. Fluid inclusions in many porphyry copper deposits contain 5-10 ??m 'daughter' crystals thought to be anhydrite but too small for identification by the previous Raman technique. Using the new instrument, we have verified that such daughter crystals in quartz from Bingham, Utah, are anhydrite. They may form by leakage of hydrogen causing internal autooxidation of sulfide ion. Daughter crystals were also examined in apatite (Durango, Mexico) and emerald (Muzo, Colombia). Valid analyses of sulfur species in solution in small fluid inclusions from ore deposits would be valuable, but are generally impossible by conventional methods. We present a calibration procedure for analyses for SO42- in such inclusions from Bingham, Utah (12,000 ?? 4000 ppm) and Creede, Colo. (probably < 500 ppm). A fetid Brazilian quartz, originally thought to contain liquid H2S, is shown to contain only HS- in major amounts. ?? 1979.

  9. Nanodelivery of bioactive components for food applications: types of delivery systems, properties, and their effect on ADME profiles and toxicity of nanoparticles.

    PubMed

    Borel, T; Sabliov, C M

    2014-01-01

    Food bioactives are known to prevent aging, cancer, and other diseases for an overall improved health of the consumer. Nanodelivery provides a means to control stability, solubility, and bioavailability, and also provides controlled release of food bioactives. There are two main types of nanodelivery systems, liquid and solid. Liquid nanodelivery systems include nanoemulsions, nanoliposomes, and nanopolymersomes. Solid nanodelivery systems include nanocrystals, lipid nanoparticles, and polymeric nanoparticles. Each type of nanodelivery system offers distinct benefits depending on the compatibility of nanoparticle properties with the properties of the bioactive and the desired application. Physicochemical properties of nanoparticles such as size, charge, hydrophobicity, and targeting molecules affect the absorption, distribution, metabolism, and excretion (ADME) of nanodelivery systems. The fate of the bioactive depends on its physicochemical properties and the location of its release. The safety of nanodelivery systems for use in food applications is largely unknown. Toxicological studies consisting of a combination of in silico, in vitro, and in vivo studies are needed to reveal the safety of nanodelivery systems for successful applications in food and agriculture. PMID:24387603

  10. X-Rays Compton Detectors For Biomedical Application

    SciTech Connect

    Rossi, Paolo; Fontana, Cristiano Lino; Moschini, Giuliano [Department of Physics of the Universityof Padua and INFN, via Marzolo 8, Padua 35131 (Italy); Baldazzi, Giuseppe; Navarria, Francesco [Department of Physics, University , Bologna (Italy); INFN, Bologna (Italy); Battistella, Andrea; Bello, Michele [National Laboratories of Legnaro, INFN, Legnaro (Padua) (Italy); Bollini, Dante [INFN, Bologna (Italy); Bonvicini, Valter; Rashevsky, Alexander; Zampa, Gianluigi; Zampa, Nicola; Vacchi, Andrea [INFN, Trieste (Italy); Gennaro, Gisella [Veneto Institute of Oncology IOV - IRCCS, Padua (Italy); Uzunov, Nikolay [National Laboratories of Legnaro, INFN, Legnaro (Padua) (Italy); Faculty of Natural Sciences, Shumen University, Shumen (Bulgaria)

    2011-06-01

    Collimators are usually needed to image sources emitting X-rays that cannot be focused. Alternately, one may employ a Compton Camera (CC) and measure the direction of the incident X-ray by letting it interact with a thin solid, liquid or gaseous material (Tracker) and determine the scattering angle. With respect to collimated cameras, CCs allow higher gamma-ray efficiency in spite of lighter geometry, and may feature comparable spatial resolution. CCs are better when the X-ray energy is high and small setups are required. We review current applications of CCs to Gamma Ray Astronomy and Biomedical systems stressing advantages and drawbacks. As an example, we focus on a particular CC we are developing, which is designed to image small animals administered with marked pharmaceuticals, and assess the bio-distribution and targeting capability of these latter. This camera has to address some requirements: relatively high activity of the imaged objects; detection of gamma-rays of different energies that may range from 140 keV (Tc99m) to 511 keV; presence of gamma and beta radiation with energies up to 2 MeV in case of 188Re. The camera consists of a thin position-sensitive Silicon Drift Detector as Tracker, and a further downstream position-sensitive system employing scintillating crystals and a multi-anode photo-multiplier (Calorimeter). The choice of crystal, pixel size, and detector geometry has been driven by measurements and simulations with the tracking code GEANT4. Spatial resolution, efficiency and scope are discussed.

  11. Synthesis and applications of RNAs with position-selective labelling and mosaic composition.

    PubMed

    Liu, Yu; Holmstrom, Erik; Zhang, Jinwei; Yu, Ping; Wang, Jinbu; Dyba, Marzena A; Chen, De; Ying, Jinfa; Lockett, Stephen; Nesbitt, David J; Ferré-D'Amaré, Adrian R; Sousa, Rui; Stagno, Jason R; Wang, Yun-Xing

    2015-06-18

    Knowledge of the structure and dynamics of RNA molecules is critical to understanding their many biological functions. Furthermore, synthetic RNAs have applications as therapeutics and molecular sensors. Both research and technological applications of RNA would be dramatically enhanced by methods that enable incorporation of modified or labelled nucleotides into specifically designated positions or regions of RNA. However, the synthesis of tens of milligrams of such RNAs using existing methods has been impossible. Here we develop a hybrid solid-liquid phase transcription method and automated robotic platform for the synthesis of RNAs with position-selective labelling. We demonstrate its use by successfully preparing various isotope- or fluorescently labelled versions of the 71-nucleotide aptamer domain of an adenine riboswitch for nuclear magnetic resonance spectroscopy or single-molecule Förster resonance energy transfer, respectively. Those RNAs include molecules that were selectively isotope-labelled in specific loops, linkers, a helix, several discrete positions, or a single internal position, as well as RNA molecules that were fluorescently labelled in and near kissing loops. These selectively labelled RNAs have the same fold as those transcribed using conventional methods, but they greatly simplify the interpretation of NMR spectra. The single-position isotope- and fluorescently labelled RNA samples reveal multiple conformational states of the adenine riboswitch. Lastly, we describe a robotic platform and the operation that automates this technology. Our selective labelling method may be useful for studying RNA structure and dynamics and for making RNA sensors for a variety of applications including cell-biological studies, substance detection, and disease diagnostics. PMID:25938715

  12. Cartographie de l'elevation de l'interface eau douce-eau salee aux iles-de-la-madeleine par la methode electromagnetique transitoire (TEM)

    NASA Astrophysics Data System (ADS)

    Madani, Abdelhamid

    This research project is dedicated to mapping the elevation of the freshwater-saltwater interface in Magdalen Islands using the transient electromagnetic method (TEM) in order to monitor time-varying quality of groundwater tables. Seventy-three TEM soundings were conducted between May 2010 and June 2011 close to Well regions in Fatima, Étang-du-Nord, Havre-Aux-Maisons, Grande-Entrée and Grosse-Île. TEM soundings were carried out with loops of 50 m x 50 m and 60 m x 40 m x 2 turns except some surveys of 100 m x 100 m. To control water quality and help constrain the interpretation of TEM soundings, conductivity logs were made in four previous exploration wells and fifteen wells drilled in 2009. Results show that saline water is associated with a low resistivity level between 2 and 4 ?.m and its elevation ranges from -40 m at Grand-Entrée and more than -250 m at Havre-Aubert. In Étang-du-Nord east, Fatima east and Grande-Entrée, saline water is shallow near shore and plunges inward as expected by the Ghyben Herzberg relation. These three areas have been identified to achieve the time-lapse monitoring of groundwater because of the risk associated with the proximity of wells in operation and the low elevation of saline water. Fatima center area close to FAT03 and FAT07 soundings and Havre-Aux-Maisons showed inconsistent results with the hydrogeological model, further work is recommended to verify the origin of the conductive areas highlighted. However, the results of the interpretation of areas at Havre-Aubert and Grosse-Île did not show a risk of contamination due to the depth of saline water. Modeling of the transition zone between the freshwater aquifer and the saline groundwater has demonstrated that it was difficult to solve it for thicknesses below 10 m and 30 m to depths of 40 and 130 m respectively. If the resistivity of the transition zone is known, the resolution is improved (5 and 10 m respectively). TEM soundings showed negative responses at late time associated with induced polarization (IP) effects. The inversion results of TEM soundings affected by this effect have shown that this dispersion most likely originates from near-surface layers. Chargeabilities ranging from 0.8 to 0.9 were obtained on the TEM soundings processed. The origin of this chargeability is currently unknown but could be related to the presence of fine material (clay). IP effect has not prevented determination of the saline water to a maximum depth of 250 m. The laboratory tests on core samples were unfortunately not able to determine the relationship between resistivity and water resistivity of saturated red sandstone. Immersion of cores in deionized water failed to eliminate the salt present in it. For time-varying monitoring of groundwater, we recommend performing drilling through the interface between freshwater and saltwater on selected areas, to conduct conductivity logs to fully characterize the level of this interface, to install multiparameter probes (conductivity, temperature, pressure) in monitoring wells located at different levels and to locate sites of TEM soundings in the vicinity that will be used to monitor the groundwater.

  13. Remote sensing in environmental police investigations: aerial platforms and an innovative application of thermography to detect several illegal activities.

    PubMed

    Lega, M; Ferrara, C; Persechino, G; Bishop, P

    2014-12-01

    Being able to identify the environmental crimes and the guilty parties is central to police investigations, and new technologies enable the authorities to do this faster and more accurately than ever before. In recent years, our research team has introduced the use of a range of aerial platforms and an innovative application of thermography to detect several illegal activities; for example, illegal sanitary sewer and storm-drain connections, illicit wastewater discharges, and other "anomalies" on surface waters can be easily identified using their thermal infrared signatures. It can also be used to detect illegal solid/liquid waste dumps or illicit air discharges. This paper introduces first results of a Thermal Pattern and Thermal Tracking approach that can be used to identify different phenomena and several pollutants. The aims of this paper were to introduce a fingerprint paradigm for environmental police investigations, defining several specific signatures (patterns) that permit the identification of an illicit/anomalous activity, and establish a procedure to use this information to find the correlation (tracking) between the crime and the culprit or the source and the target. PMID:25154683

  14. Full dimensional Franck-Condon factors for the acetylene A? (1)Au-X? (1)?(g)(+) transition. II. Vibrational overlap factors for levels involving excitation in ungerade modes.

    PubMed

    Park, G Barratt; Baraban, Joshua H; Field, Robert W

    2014-10-01

    A full-dimensional Franck-Condon calculation has been applied to the A? (1)Au-X? 1?g+ transition in acetylene in the harmonic normal mode basis. Details of the calculation are discussed in Part I of this series. To our knowledge, this is the first full-dimensional Franck-Condon calculation on a tetra-atomic molecule undergoing a linear-to-bent geometry change. In the current work, the vibrational intensity factors for levels involving excitation in ungerade vibrational modes are evaluated. Because the Franck-Condon integral accumulates away from the linear geometry, we have been able to treat the out-of-plane component of trans bend (?4('')) in the linear X? state in the rotational part of the problem, restoring the ? Euler angle and the a-axis Eckart conditions. A consequence of the Eckart conditions is that the out-of-plane component of ?4('') does not participate in the vibrational overlap integral. This affects the structure of the coordinate transformation and the symmetry of the vibrational wavefunctions used in the overlap integral, and results in propensity rules involving the bending modes of the X? state that were not previously understood. We explain the origin of some of the unexpected propensities observed in IR-UV laser-induced fluorescence spectra, and we calculate emission intensities from bending levels of the A? state into bending levels of the X? state, using normal bending mode and local bending mode basis sets. Our calculations also reveal Franck-Condon propensities for the Cartesian components of the cis bend (?5('')), and we predict that the best A?-state vibrational levels for populating X?-state levels with large amplitude bending motion localized in a single C-H bond (the acetylene?vinylidene isomerization coordinate) involve a high degree of excitation in ?6(') (cis-bend). Mode ?4(') (torsion) populates levels with large amplitude counter-rotational motion of the two hydrogen atoms. PMID:25296804

  15. Teeth and bones: applications of surface science to dental materials and related biomaterials

    NASA Astrophysics Data System (ADS)

    Jones, F. H.

    2001-05-01

    Recent years have seen a considerable upsurge in publications concerning the surface structure and chemistry of materials with biological or biomedical applications. Within the body, gas-solid interactions become relatively less significant and solid-liquid or solid-solid interfaces dominate, providing new challenges for the surface scientist. The current paper aims to provide a timely review of the use of surface analysis and modification techniques within the biomaterials field. A broad overview of applications in a number of related areas is given with particular attention focusing on those materials commonly encountered in dentistry and oral or maxillofacial implantology. Several specific issues of current interest are discussed. The interaction between synthetic and natural solids, both in the oral environment and elsewhere in the body is important in terms of adhesion, related stresses and strains and ultimately the longevity of a dental restoration, biomedical implant, or indeed the surrounding tissue. Exposure to body fluids, of course, can also affect stability, leading to the degradation or corrosion of materials within the body. Whilst this could potentially be harmful, e.g., if cytotoxic elements are released, it may alternatively provide a route to the preferential release of beneficial substances. Furthermore, in some cases, the controlled disintegration of a biomaterial is desirable, allowing the removal of an implant, e.g., without the need for further surgery. The presence of cells in the immediate bioenvironment additionally complicates the situation. A considerable amount of current research activity is targeted at the development of coatings or surface treatments to encourage tissue growth. If this is to be achieved by stimulating enhanced cell productivity, determination of the relationship between cell function and surface composition is essential.

  16. Profil comparatif et évolutif des personnes infectées par le virus de l'immunodéficience humaine traitées aux antirétroviraux à Kinshasa, République Démocratique du Congo

    PubMed Central

    Koy, Tshingani; Mukumbi, Henri; Malandala, Ghislain Lubangi Muteba; Donnen, Philippe; Wilmet–Dramaix, Michèle

    2014-01-01

    Introduction A trithérapie (ARV) introduite en R.D.Congo en 1996, a permis l?amélioration substantielle de la qualité de vie des PVVIH et a réduit la morbimortalité liée au sida en R.D. Congo. L'objectif de cette étude est de présenter le profil épidémiologique comparatif, clinique, ainsi que l’évolution anthropométrique des PVVIH sous ARV à Kinshasa. Méthodes Etude de cohorte sur 438 PVVIH, de 18 ans et plus, suivies entre mai 2010 à 2011 à Amo Congo à Kinshasa. Une comparaison a été faite entre les patients suivis pendant un an et ceux perdus de vue. Le Chi carré de Mc Nemar et l'analyse de variance pour mesures répétées ont été appliqués pour étudier l’évolution. Résultats Près 12 mois de suivi, 11,4% de patients ont été perdus de vue. Parmi eux, on observait des proportions significativement plus élevées de personnes de niveau socioéconomique bas, d'indice de masse corporelle (IMC) bas, présentant de l'anorexie, des affections opportunistes. Les proportions de patients aux stades OMS 3 & 4 et naïfs étaient également significativement plus élevées et la durée sous ARV plus courte. Les gains moyens des paramètres anthropométriques au 12ème mois, étaient importants: de 3,6 [3,2 - 4,0] kg pour le poids, 1,8 (1,4 - 2,3) cm pour le périmètre abdominal, 0,9 (0,8 - 1,2) cm pour le périmètre brachial, 1,4 (1,2 - 1,5) kg/m2 pour l'IMC. La proportion de patients avec un IMC <18,5 kg/m2 a significativement plus baissé entre l'admission et le 12ème mois parmi les patients sans stomatite que parmi ceux avec stomatite. L'IMC moyen évoluait significativement différemment entre l'admission et le 12ème mois selon l’âge et la taille de ménage. Conclusion Les facteurs fragilisant la rétention des patients sous antirétroviraux et une évolution progressive de l’état nutritionnel ont été observés. PMID:25995784

  17. Les recommandations thérapeutiques relatives aux effets secondaires extrapyramidaux associés à l’utilisation d’antipsychotiques de deuxième génération chez les enfants et les adolescents

    PubMed Central

    Pringsheim, Tamara; Doja, Asif; Belanger, Stacey; Patten, Scott

    2012-01-01

    HISTORIQUE ET OBJECTIF : L’utilisation d’antipsychotiques augmente chez les enfants. Le présent article visait à orienter les cliniciens quant à la prise en charge clinique des effets secondaires extrapyramidaux des antipsychotiques de deuxième génération. MÉTHODOLOGIE : Les publications, les entrevues avec des informateurs clés et des échanges avec les membres d’un groupe de discussion et les partenaires ont permis de déterminer les principaux secteurs cliniques d’orientation et les préférences quant à la structure des présentes recommandations. Les membres responsables des lignes directrices ont reçu le projet de recommandations, ont évalué l’information recueillie grâce à une analyse bibliographique systématique et ont utilisé un processus de groupe nominal pour parvenir à un consensus quant aux recommandations thérapeutiques. Les lignes directrices contiennent une description des anomalies neurologiques souvent observées avec l’utilisation d’antipsychotiques ainsi que les recommandations sur le moyen d’examiner et de quantifier ces anomalies. Une démarche séquentielle sur la prise en charge des anomalies neurologiques est présentée. RÉSULTATS : On peut observer plusieurs types de symptômes extrapyramidaux attribuables à l’utilisation d’antipsychotiques chez les enfants, y compris la dystonie aiguë, l’akathisie, le parkinsonisme et la dyskinésie tardive, toutes induites par les neuroleptiques, de même que la dystonie tardive, l’akathisie tardive et les dyskinésies de sevrage. La forte majorité des données probantes sur le traitement des troubles du mouvement induits par les antipsychotiques proviennent de patients adultes atteints de schizophrénie. Étant donné le peu de données pédiatriques, les recommandations découlent de publications portant tant sur des adultes que sur des enfants. Compte tenu des limites de généralisation des données provenant de sujets adultes pour des enfants, il faudrait évaluer ces recommandations d’après les avis d’experts plutôt que d’après les données probantes. CONCLUSION : Les cliniciens doivent savoir que les antipsychotiques de deuxième génération ont le potentiel d’induire des effets secondaires neurologiques et devraient faire preuve d’une extrême vigilance lorsqu’ils en prescrivent. PMID:24082814

  18. Octobre 2014 Vice-rectorat aux tudes et aux activits

    E-print Network

    Garnier Secrétaire : Diane Boucher Vice-rectrice adjointe : Nicole Lacasse Secrétaire : Marie-France Montreuil Vice-recteur adjoint : François Pothier Secrétaire : Nataly Aubert RECTORAT Recteur : Denis Brière

  19. Novembre 2013 Vice-rectorat aux tudes et aux activits

    E-print Network

    Garnier Secrétaire : Diane Boucher Vice-rectrice adjointe : Nicole Lacasse Secrétaire : Marie-France Montreuil Vice-recteur adjoint : François Pothier Secrétaire : Nataly Aubert RECTORAT Recteur : Denis Brière

  20. Septembre 2014 Vice-rectorat aux tudes et aux activits

    E-print Network

    Garnier Secrétaire : Diane Boucher Vice-rectrice adjointe : Nicole Lacasse Secrétaire : Marie-France Montreuil Vice-recteur adjoint : François Pothier Secrétaire : Nataly Aubert RECTORAT Recteur : Denis Brière

  1. Mathmatiques Gnrales premire anne Introduction aux quations aux drives partielles

    E-print Network

    Mironescu, Petru

    vérifiée. i) Montrer qu'il existe une suite (uj)jN de V telle que pour tout j N , uj L2() = 1 et uj L2 On pose P(x) = 1 (4)n/2 e-|x|2/4 et S(0)f(x) = f(x), S(t)f(x) = P t f(x), t > 0, x Rn . Si f X, alors S point x , on note n(x) la normale extérieure unitaire. Soit f L2 (). On considère le problème suivant

  2. Mathmatiques Gnrales premire anne Introduction aux quations aux drives partielles

    E-print Network

    Mironescu, Petru

    aij(x) est mesurable, i, j 1, n . 1 #12;a) On suppose u C2 ()C() solution classique de (6). Montrer continue et bornée} Muni de la norme L(Rn), X est un espace de Banach . 2 On pose P(x) = 1 (4)n/2 e-|x|2/4 et P(x) = 1 n P(x/), > 0. On définit le semi-groupe de la chaleur par les formules S(0)f(x) = f

  3. Scaling of three-dimensional interconnect technology incorporating low temperature bonds to pitches of 10 µm for infrared focal plane array applications

    NASA Astrophysics Data System (ADS)

    Temple, Dorota S.; Lueck, Matthew R.; Malta, Dean; Vick, Erik P.

    2015-03-01

    This paper focuses on the application of low temperature bonding to the fabrication of three-dimensional (3D) massively parallel signal processors for high performance infrared imagers. We review two generations of the 3D heterogeneous integration process. The first generation process, compatible with pixel sizes in the 20 to 30 µm range, relies on low temperature epoxy bonding that is followed by the formation of copper-filled through-silicon vias (TSVs). The second generation process, scalable to pixel sizes of 10 µm and smaller, employs solid–liquid diffusion bonding of copper–tin to copper at 250 °C the bonding follows TSV fabrication. To demonstrate the second generation process, we fabricated 3D test vehicles in the form of 640 × 512 arrays of vertical interconnects composed of TSVs and metal–metal bonds on a 10 µm pitch. We characterized electrical conductivity of the interconnects, the isolation resistance between the interconnects, and the operability and yield of the arrays. The successful demonstration of the interconnect technology paves the way to a functional demonstration of 3D signal processors in infrared imagers with 10 µm pixels.

  4. Les allergies alimentaires aux fruits

    Microsoft Academic Search

    P. Rougé; J.-P. Borges; R. Culerrier; C. Brulé; A. Didier; A. Barre

    2009-01-01

    Edible fruit contain many distinct allergens that mainly correspond to Pathogenesis Related-proteins (PR-proteins). According to their wide distribution in plant tissues, these PR-proteins consist of panallergens. They belong to different groups of PR-proteins like PR-2 (1,3?-glucanases), PR-3 (class I chitinases), PR-4 (germin-like proteins), PR-5 (thaumatin-like proteins or TLP), PR-10 (Bet v 1-like proteins), and PR-14 (lipid transfer proteins or LTP).

  5. INTRODUCTION AUX HOMME-MACHINE

    E-print Network

    Essert-Villard, Caroline

    fonction de la perception visuelle puis tactile 10 Action physique · la main est la plus utilisée par les agit · actuellement, les systèmes interactifs expoitent peu l'interaction bimanuelle #12;3 13 Cognition secondes · mémoire à long terme capacité infinie temps de stockage infini 14 Cognition : mémoire et

  6. Article original Rsistance aux antiseptiques

    E-print Network

    Paris-Sud XI, Université de

    genres bactériens) a été analysée vis-à-vis de 4 antiseptiques (cétrimide, chlorhexidine, hexachlorophène, kanamycine, tétracycline). Pour 3 anti- septiques (cétrimide, chlorhexidine, chlorure mercurique) la, chlorhexidine, hexachlorophène) ou entre ces antiseptiques et des antibiotiques pour P cepacia, S marcescens

  7. Manifestations dysimmunitaires associées aux lymphomes

    Microsoft Academic Search

    F. Jardin; H. Lévesque; H. Tilly

    2005-01-01

    Purpose. – A wide spectrum of auto-immune manifestations is frequently reported in non-Hodgkin’s lymphoma (NHL). The purpose of the review is to describe the immune manifestations observed in NHL, according to their histological subtype and to discuss the current physiopathological hypothesis with their therapeutic relevance.Current knowledge and key points. – Most of the organs can be targeted by an immune

  8. Influence of hydro-climatic conditions, soil type, and application matrix on potential vadose zone export of PPCPs

    NASA Astrophysics Data System (ADS)

    Gall, H. E.; Rao, P.; O'Connor, G.

    2013-12-01

    The land-application of biosolids and animal manure to agricultural fields has the potential to negatively impact the quality of nearby surface and subsurface water due to the presence of emerging contaminants in these residuals. We investigated the extent to which the vadose zone acts as a hydrologic and biogeochemical filter of two emerging contaminants, Triclosan (TCS) and estrone (E1) using a coupled source zone and vadose zone modeling approach. Monte Carlo simulations were run for a year following residual applications to explore the following research questions: (1) how does the application matrix (e.g., de-watered solids, liquid lagoon effluent, etc.) affect PPCP mass fluxes?; (2) how do hydro-climatic conditions and soil type affect PPCP mass fluxes?; (3) what role does the presence of macropore pathways play in PPCP export from the vadose zone; and (4) does the long-term, repeated application of residuals affect the ability of the vadose zone to act as an effective biogeochemical filter? The simulations were conducted for a sub-tropical climate with sand (e.g., Florida) and a humid climate with a silty clay loam (e.g., Midwestern United States). Simulation results suggest that the potential mobility of emerging contaminants increases linearly with increasing fraction applied to the mobile phase of the source zone (i.e., higher PPCP mass fraction in the dissolved phase during application). Following a single application, the total amount of PPCP mass exported from the source zone over the course of a year can be as high as 70% in a sub-tropical climate with sand soil. However, these types of soils do not have macropore flow pathways and the annual PPCP mass exported from the vadose zone is less than 1% of the mass applied. The higher organic carbon content in a silty clay loam reduces the amount of PPCP mass released from the source zone to less than 5% of the mass applied. In the presence of macropore pathways, the silty clay loam's vadose zone acts as a less effective biogeochemical filter than the sand's vadose zone. However, following a single application, Monte Carlo simulations suggest that the annual mass exported from the silty clay loam's vadose zone is less than 0.2% of the applied mass. Additionally, simulation results suggest that the mass exported from the vadose zone of the silty clay loam increases with time when fields receive long-term, repeated residual applications. Thus, field studies conducted with single applications likely underestimate mass fluxes exported from fields with a history of applications.

  9. Carbon-Based Wear Coatings: Properties and Applications

    NASA Technical Reports Server (NTRS)

    Miyoshi, Kazuhisa

    2003-01-01

    The technical function of numerous engineering systems - such as vehicles, machines, and instruments - depends on the processes of motion and on the surface systems. Many processes in nature and technology depend on the motion and dynamic behavior of solids, liquids, and gases. Smart surface systems are essential because of the recent technological push toward higher speeds, loads, and operating temperatures; longer life; lighter weight and smaller size (including nanotechnology); and harsh environments in mechanical, mechatronic, and biomechanical systems. If proper attention is not given to surface systems, then vehicles, machines, instruments, and other technical systems could have short lives, consume excessive energy, experience breakdowns, result in liabilities, and fail to accomplish their missions. Surface systems strongly affect our national economy and our lifestyles. At the NASA Glenn Research Center, we believe that proper attention to surface systems, especially in education, research, and application, could lead to economic savings of between 1.3 and 1.6 percent of the gross domestic product. Wear coatings and surface systems continue to experience rapid growth as new coating and surface engineering technologies are discovered, more cost-effective coating and surface engineering solutions are developed, and marketers aggressively pursue, uncover, and exploit new applications for engineered surface systems in cutting tools and wear components. Wear coatings and smart surface systems have been used widely in industrial, consumer, automotive, aerospace, and biomedical applications. This presentation expresses the author's views of and insights into smart surface systems in wear coatings. A revolution is taking place in carbon science and technology. Diamond, an allotrope of carbon, joins graphite, fullerenes, and nanotubes as its major pure carbon structures. It has a unique combination of extreme properties: hardness and abrasion resistance; adhesion and friction; thermal conductivity; chemical and thermal inertness; corrosion and wear resistance; radiation resistance and biocompatibility; electronic, acoustic, and electrochemical characteristics; and environmental compatibility. These properties make diamond attractive for a wide range of diverse applications. In particular, chemical-vapor-deposited (CVD) diamond coatings offer a broad potential, since size and cost are not as limiting. The production of large, superhard diamond films or sheets at low cost make designer materials possible. This presentation is divided into two sections: properties and applications of hard coatings. The first section is concerned with the fundamental properties of the surfaces of CVD diamonds and related materials. The surface properties of hard coatings with favorable coefficients of friction (less than or equal to 0.1) and dimensional wear coefficients (less than or equal to 10(exp -6) cubic millimeters/N.m) in specific environments are discussed. The second section is devoted to applications. Examples of actual, successful applications and of potential challenging applications of the coatings.such as CVD diamond, diamondlike carbon, and cubic boron nitride-are described. Cutting tools coated with CVD diamond are of immediate commercial interest. Other applications, such as microelectromechanical systems (MEMS), valves, and bearings of CVD diamond, are being developed, but at a slow pace. There is a continually growing interest in commercializing diamondlike carbon for wear parts applications, such as biomedical parts and implants, forming dies, transport guides, magnetic tapes and disks, valves, and gears. Cubic boron nitride films are receiving attention because they can be used on tools to machine ferrous materials or on wear parts in sliding contact with ferrous materials.

  10. Recent Applications of Laser-Induced Breakdown Spectrometry: A Review of Material Approaches

    Microsoft Academic Search

    Jianyong Wu; Joseph Sneddon

    2004-01-01

    The use of laser?induced breakdown spectrometry (LIBS) has grown steadily, and it has proven to be a relatively dynamic research activity for performing direct spectrochemical elemental or metal analysis of a variety of materials, solids, liquids, and gases, with none or little sample pretreatment procedures. Significant progress has been made during the last several years on the diverse and versatile

  11. Ellipsometry on thin organic layers of biological interest: characterization and applications

    Microsoft Academic Search

    Hans Arwin

    2000-01-01

    The thickness resolution and in situ advantage of ellipsometry make this optical technique particularly suitable for studies of thin organic layers of biological interest. Early ellipsometric studies in this area mainly provided thickness quantification, often expressed in terms of surface mass. However, today it is possible to perform monolayer spectroscopy, e.g. of a protein layer at a solid\\/liquid interface, and

  12. A gravity independent biological grey water treatment system for space applications

    Microsoft Academic Search

    Majda'midhat Nashashibi

    2002-01-01

    Biological treatment of grey water in space presents serious challenges, stemming mainly from microgravity conditions. The major concerns are phase separation and mass transfer limitations. To overcome solid-liquid phase separation, novel immobilized cell packed bed (ICPB) bioreactors have been developed to treat synthetic grey water. Packed bed bioreactors provide a unique environment for attached microbial growth resulting in high biomass

  13. Nanofluids: A New Field of Scientific Research and Innovative Applications

    Microsoft Academic Search

    2008-01-01

    In the early 1990s, as I began exploring ways to apply nanotechnology to heat transfer engineering, I saw the possibility of breaking down the century-old technical barriers of conventional solid-liquid suspensions by stably suspending nanoparticles. During the past decade, a series of pioneering experiments have discovered that nanofluids exhibit a number of novel thermal transport phenomena. Nanofluids are of great

  14. Plasma synthesis of semiconductor nanocrystals for nanoelectronics and luminescence applications

    Microsoft Academic Search

    Uwe Kortshagen; Lorenzo Mangolini; Ameya Bapat

    Functional nanocrystals are widely considered as novel building blocks for nanostructured materials and devices. Numerous\\u000a synthesis approaches have been proposed in the solid, liquid and gas phase. Among the gas phase approaches, low pressure nonthermal\\u000a plasmas offer some unique and beneficial features. Particles acquire a unipolar charge which reduces or eliminates agglomeration;\\u000a particles can be electrostatically confined in a reactor

  15. Plasma synthesis of semiconductor nanocrystals for nanoelectronics and luminescence applications

    Microsoft Academic Search

    Uwe Kortshagen; Lorenzo Mangolini; Ameya Bapat

    2007-01-01

    Functional nanocrystals are widely considered as novel building blocks for nanostructured materials and devices. Numerous\\u000a synthesis approaches have been proposed in the solid, liquid and gas phase. Among the gas phase approaches, low pressure nonthermal\\u000a plasmas offer some unique and beneficial features. Particles acquire a unipolar charge which reduces or eliminates agglomeration;\\u000a particles can be electrostatically confined in a reactor

  16. Application Name:_________________________________________

    E-print Network

    Fraden, Seth

    application to WGS Program Office, Rabb 105. Applications and additional information is available on the Women's and Gender Studies website at www.brandeis.edu/programs/wgs or WGS Program Office, Rabb 105. CONTACT Shannon BY 5 PM Submit completed application to WGS Program Office, Rabb 105. Applications and additional

  17. Application Bar

    Microsoft Academic Search

    Henry Lee; Eugene Chuvyrov

    \\u000a When you’re ready to program your Windows Phone 7 application in Visual Studio, you’ll know what general features your application\\u000a will provide. Each of the major application features will need to be accessible via a shortcut or some form of a navigation\\u000a menu. For Windows Phone 7 applications, Microsoft recommends that you use a standard Windows Phone 7 Application Bar

  18. Microgravity Science and Applications: Program Tasks and Bibliography for Fiscal Year 1996

    NASA Technical Reports Server (NTRS)

    1997-01-01

    NASA's Microgravity Science and Applications Division (MSAD) sponsors a program that expands the use of space as a laboratory for the study of important physical, chemical, and biochemical processes. The primary objective of the program is to broaden the value and capabilities of human presence in space by exploiting the unique characteristics of the space environment for research. However, since flight opportunities are rare and flight research development is expensive, a vigorous ground-based research program, from which only the best experiments evolve, is critical to the continuing strength of the program. The microgravity environment affords unique characteristics that allow the investigation of phenomena and processes that are difficult or impossible to study an Earth. The ability to control gravitational effects such as buoyancy driven convection, sedimentation, and hydrostatic pressures make it possible to isolate phenomena and make measurements that have significantly greater accuracy than can be achieved in normal gravity. Space flight gives scientists the opportunity to study the fundamental states of physical matter-solids, liquids and gasses-and the forces that affect those states. Because the orbital environment allows the treatment of gravity as a variable, research in microgravity leads to a greater fundamental understanding of the influence of gravity on the world around us. With appropriate emphasis, the results of space experiments lead to both knowledge and technological advances that have direct applications on Earth. Microgravity research also provides the practical knowledge essential to the development of future space systems. The Office of Life and Microgravity Sciences and Applications (OLMSA) is responsible for planning and executing research stimulated by the Agency's broad scientific goals. OLMSA's Microgravity Science and Applications Division (MSAD) is responsible for guiding and focusing a comprehensive program, and currently manages its research and development tasks through five major scientific areas: biotechnology, combustion science, fluid physics, fundamental physics, and materials science. FY 1996 was an important year for MSAD. NASA continued to build a solid research community for the coming space station era. During FY 1996, the NASA Microgravity Research Program continued investigations selected from the 1994 combustion science, fluid physics, and materials science NRAS. MSAD also released a NASA Research Announcement in microgravity biotechnology, with more than 130 proposals received in response. Selection of research for funding is expected in early 1997. The principal investigators chosen from these NRAs will form the core of the MSAD research program at the beginning of the space station era. The third United States Microgravity Payload (USMP-3) and the Life and Microgravity Spacelab (LMS) missions yielded a wealth of microgravity data in FY 1996. The USMP-3 mission included a fluids facility and three solidification furnaces, each designed to examine a different type of crystal growth.

  19. CONTROL ASSAY DEVELOPMENT: METHODOLOGY AND LABORATORY VERIFICATION

    EPA Science Inventory

    The report describes Control Assay Development (CAD), a data acquisition program designed to evaluate the potential applicability of various treatment processes for the control of solid, liquid, and gaseous emissions from coal conversion plants. The CAD program described could be...

  20. 40 CFR 227.5 - Prohibited materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...without limitation, solids, liquids, semi-liquids, gases or organisms) produced or used for radiological, chemical or biological warfare; (c) Materials insufficiently described by the applicant in terms of their compositions and...