Polymer chain generation for coarse-grained models using radical-like polymerization

An innovative method is proposed to generate configurations of coarse grained models for polymer melts. This method, largely inspired by chemical ``radical polymerization'', is divided in three stages: (i) nucleation of radicals (reacting molecules caching monomers); (ii) growth of chains within a solvent of monomers; (iii) termination: annihilation of radicals and removal of residual monomers. The main interest of this method is that relaxation is performed as chains are generated. Pure mono and poly-disperse polymers melts are generated and compared to the configurations generated by the Push Off method from Auhl et al.. A detailed study of the static properties (gyration radius, mean square internal distance, entanglement length) confirms that the radical-like polymerization technics is suitable to generate equilibrated melts. The method is flexible, and can be adapted to generate nano-structured polymers, namely diblock and triblock copolymers.Comment: 9 pages, 12 figure

Which electricity market design to encourage the development of demand response?

International audienceDemand response is a cornerstone problem in electricity markets under climate change constraints. Most liberalized electricity markets have a poor track record at encouraging the deployment of smart meters and the development of demand response. In Europe, different models are considered for demand response, from a development under a regulated regime to a development under competitive perspectives. In this paper focusing on demand response and smart metering for mid-­‐size and small consumers, we investigate which types of market signals should be sent to demand managers to see demand response emerge as a competitive activity. Using data from the French power system over nine years , we compare the possible market design options which would enable the development of demand response. Our simulations demonstrate that under the current market rules demand response is not a profitable activity in the French electricity industry. Introducing a capacity market could bring additional revenues to demand response providers and improve incentives to put in place demand response programs in a market environment

Contribution à l'étude du comportement mécanique des éléments bicouches sous sollicitations statiques et cycliques

Ce travail porte sur le comportement structural des réparations minces en béton soumises aux chargements mécaniques monotones et cycliques. L'objectif est l'étude des mécanismes susceptibles d'engendrer l'apparition et la propagation de fissuration au niveau de l'interface. L'étude s'intéresse particulièrement à l'influence du mode de sollicitation sur la fissuration interfaciale et à la durabilité des éléments composites La méthodologie repose sur trois étapes expérimentales. La première concerne le comportement structural d'une vaste gamme de configurations d'éléments composites en considérant une méthode unique de préparation de surface. La seconde met l'accent sur le rôle de cette préparation sur les mécanismes de décollement. La dernière aborde la sensibilité du comportement des structures composites en présence de défaut de collage. Les résultats montrent que lorsque le plan interfacial est suffisamment rugueux ([alpha]rugo [supérieur ou égal à] 10 [degré]), il n'y a pas de décollement quel que que soit le type de sollicitation. Globalement, les résultats obtenus démontrent que les réparations minces adhérentes en béton se comportent très bien lors des chargements monotones et cycliques et que dans des conditions de mise en oeuvre adéquates et avec des matériaux de qualité, elles constituent une alternative de réhabilitation viable et pertinente dans plusieurs situations

Spirobicyclic and Tetracyclic Pyrazolidinones: Syntheses and Properties

International audienceThe stereoselective syntheses of spirobicyclic and tetracyclic pyrazolidinones are reported based on a (3+2) annu- lation between hydrazones and α-oxoketenes. Some of these conformationally constrained molecules were resolved as enantiopure materials by HPLC techniques and evaluated as amino- catalysts for iminium activation in a model Diels–Alder cyclo- addition

Borel summability of the 1/N expansion in quartic O(N)-vector models

We consider a quartic O(N)-vector model. Using the Loop Vertex Expansion, we prove the Borel summability in 1/N along the real axis of the partition function and of the connected correlations of the model. The Borel summability holds uniformly in the coupling constant, as long as the latter belongs to a cardioid like domain of the complex plane, avoiding the negative real axis.Comment: 23 pages, 2 figure

Commodity Market Development in Europe – Outlook Workshop 2014. Proceedings

This report contains a summary and the presentations of the expert workshop 'Commodity Market Development in Europe – Outlook', held in October 2014 in Brussels. The workshop was held in order to present and discuss the preliminary results of the DG AGRI outlook on EU agricultural market developments. The workshop gathered high-level policy makers, modelling and market experts and provided a forum to present and discuss recent and projected developments on the EU agricultural and commodity markets, to outline the reasons behind observed and prospected developments, and to draw conclusions on the short/medium term perspectives of European agricultural markets in the context of world market developments. Special focus was given on the discussion of the influence of different settings/assumptions (regarding e.g. drivers of demand and supply, macroeconomic uncertainties, etc.) on the projected market developments.JRC.J.4-Agriculture and Life Sciences in the Econom

Une approche multi-échelle de super-résolution à partir de séquences d'images

- Nous considérons le problème de la reconstruction d'une image de haute résolution à partir d'une séquence d'images de basse résolution et de la mesure du mouvement entre images. Il est posé comme un problème inverse et est résolu à l'aide d'une méthode itérative appelée algorithme de Kaczmarz généralisé. Nous décrivons une implantation à faible coût de calcul basée sur l'estimation d'un modèle paramétrique 2D du mouvement global. Nous proposons également deux améliorations de cet algorithme. La première est l'utilisation d'une carte de détection du mouvement permettant de gérer les régions où le modèle de mouvement global n'est pas valide. La seconde est une approche multi-échelle permettant d'améliorer la qualité de l'estimation de mouvement au fur et à mesure du traitement de super-résolution

Magnetodielectric coupling and multi-blocking effect in the Ising-chain magnet Sr2Ca2CoMn2O9

We have demonstrated magnetodielectric (MD) coupling in an Ising-chain magnet Sr2Ca2CoMn2O9, via detailed investigation of ac susceptibility and dielectric constant as a function of temperature, magnetic field and frequency. Sr2Ca2CoMn2O9 consists of spin-chains, made of the regular stacking of one CoO6 trigonal prism with two MnO6 octahedra. The (Co2+ Mn4+ Mn4+) unit stabilizes a (up-down-up) spin-state along the chains which are distributed on a triangular lattice. This compound undergoes a partially disordered antiferromagnetic transition at TN ~ 28 K. The dielectric constant exhibits a clear peak at TN only in presence of an external magnetic field (above 5 kOe), evidencing the presence of MD coupling, which is further confirmed by field-dependent dielectric measurements. We argue that spatial inversion symmetry can be broken as a result of exchange-striction along each spin chain, inducing uncompensated local dipoles. At low temperatures, a dipolar relaxation phenomenon is observed, bearing strong similarities with the blocking effect typical of the spin dynamics in this compound. Such a spin-dipole relationship is referred to as a multi-blocking effect, in relation with the concept of magnetodielectric multiglass previously introduced for related materials.Comment: Multiferroicity, Magnetoelectric coupling, Complex exchange interaction, spin-chain oxid

Evaluation of Organogel Nanoparticles as Drug Delivery System for Lipophilic Compounds

The purpose of the study was to evaluate organogel nanoparticles as a drug delivery system by investigating their stability, according to the formulation strategy, and their release profile. The gelled nanoparticles were prepared by hot emulsification (above the gelation temperature) of an organogel in water, and cooling at room temperature. In the first step, we used DLS and DSC to select the most suitable formulations by optimizing the proportion of ingredients (HSA, PVA, castor oil) to obtain particles of the smallest size and greatest stability. Then, two lipophilic drug models, indomethacin and ketoconazole were entrapped in the nanoparticles made of castor oil gelled by 12-hydroxystearic acid. Thermal studies (DSC) confirmed that there was no significant alteration of gelling due to the entrapped drugs, even at 3% w/w. Very stable dispersions were obtained (>3 months), with gelled oil nanoparticles presenting a mean diameter between 250 and 300 nm. High encapsulation efficiency (>98%) was measured for indomethacin and ketoconazole. The release profile determined by in vitro dialysis showed an immediate release of the drug from the organogel nanoparticles, due to rapid diffusion. The study demonstrates the interest of these gelled oil nanoparticles for the encapsulation and the delivery of lipophilic active compounds

Documentation of the European Comission’s EU module of the Aglink-Cosimo modelling system

This report documents the EU module of Aglink-Cosimo model. Aglink-Cosimo is a recursive-dynamic, partial equilibrium, supply demand model of world agriculture developed by the OECD and FAO Secretariats. The model is used to simulate development of annual supply, demand and prices for the main agricultural commodities produced, consumed and traded worldwide. Aglink-Cosimo covers 44 individual countries and 12 regions, and 40 commodities clearing markets at the world level. At the EU level, the Aglink-Cosimo model is used to produce the "Prospects for Agricultural Markets and Income in the EU". This is a yearly exercise that provides a detailed overview of EU agricultural markets with a 10 year time horizon. It incorporates information from policy makers and market experts in the European Commission, stakeholders, researchers and modellers. The EU Outlook intends to provide a broad consensus about the evolution of European Agriculture in the medium-term. It serves as reference timeline for counterfactual policy analysis and market analysis done in numerous research sites in Europe. The report includes a detailed presentation and discussion of the structure and specific features of the model, along with the theoretical underpinnings. It also documents the process of calibration such as to obtain a medium-term baseline and different efforts towards the validation of results. Nonetheless, different applications in the area of uncertainty analysis and the use of partial stochastics are also included.JRC.J.4-Agriculture and Life Sciences in the Econom