Sulfur isotope fractionation during incorporation of sulfur nucleophiles into organic compounds

34S enrichment is shown to occur during sulfurization reactions and for the first time conclusively attributed to an isotope equilibrium effect rather than selective addition of 34S enriched nucleophiles

Prise en compte des interactions multi-domaines lors de l’évaluation de la fiabilité prévisionnelle des systèmes mécatroniques

The mechatronic systems are hybrid, dynamic, interactive and reconfigurable. Therefore their dysfunctional modeling is very difficult. Multi-physical interactions between components have impacts on the degradation or on system failures, leading thus to more uncertainty in reliability evaluation. The work presented in this paper aims to improve the integration of multi-domain interactions in the reliability assessment of mechatronic systems. After a presentation of the state of the art of mechatronic systems reliability estimation methods, we propose to represent multi domain interactions by influential factors in the dysfunctional model. We generally use proportional hazard models; in the case of an interaction represented by a temperature stress, Arrhenius model is used

Activité Acaricide Des Huiles Essentielles Du Mentha Pulegium, Origanum Compactum Et Thymus Capitatus Sur L’acarien Phytophage Tetranychus Urticae Koch (Acari : Tetranychidae)

The use of botanical acaricides extracted from plants as an alternative to replace the chemical acaricides is an interesting and efficient option to control pests and ameliorate their toxic effects to humans and the environment. The aim of this work was to evaluate the contact toxicity of Pennyroyal mint (Mentha pulegium), oregano (Origanum compactum) and thyme (Thymus capitatus) essential oils against adults, larvae and eggs of two-spotted spider mite Tetranychus urticae Koch (Tetranychidae). The chemical composition of these three plant essential oils was also characterized. Laboratory tests were conducted to determine the acaricidal effect of plant essential oils at several doses in geometric progression. The consequences of treatments on mortality were measured in relationships with concentrations of essential oils. On the other hand, the major constituents of the three essential oils were identified by gas chromatography-mass spectrometer (GC-MS) techniques. GCMS analyses proved that the major compound present in the essential oils of thyme and oregano is carvacrol (55.59 and 55.28% respectively) while the main component of pennyroyal mint essential oil is pulegone (67,63%). Laboratory bioassay results indicated that essential oils of thyme and pennyroyal mint caused the most important acaricidal effects in comparison with the essential oil of oregano. At a concentration of 1%, thyme and pennyroyal eradicate all adults of the mite while oregano causes a mortality of 84.99%. On larvae, the mortality rate of thyme, pennyroyal and oregano is 97.7; 89.47 and 57.89% respectively. The results of the present study concluded that plant essential oils could be useful in promoting research aiming at the development of new agent for pest control from the plants with medicinal values

Evidential Networks for Evaluating Predictive Reliability of Mechatronics Systems under Epistemic Uncertainties

In reliability predicting field, the probabilistic approaches are based on data relating to the components which can be precisely known and validated by the return of experience REX, but in the case of complex systems with high-reliability precision such as mechatronic systems, uncertainties are inevitable and must be considered in order to predict with a degree of confidence the evaluated reliability. In this paper, firstly we present a brief review of the non-probabilistic approaches. Thereafter we present our methodology for assessing the reliability of the mechatronic system by taking into account the epistemic uncertainties (uncertainties in the reliability model and uncertainties in the reliability parameters) considered as a dynamic hybrid system and characterized by the existence of multi-domain interaction between its failed components. The key point in this study is to use an Evidential Network “EN” based on belief functions and the dynamic Bayesian network. Finally, an application is developed to illustrate the interest of the proposed methodology

Dynamic Bayesian Network for Reliability of Mechatronic System with Taking Account the Multi-Domain Interaction

This article presents a methodology for reliability prediction during the design phase of mechatronic system considered as an interactive dynamic system. The difficulty in modeling reliability of a mechatronic system is mainly due to failures related to the interaction between the different domains called Multi-domain interaction. Therefore in this paper, after a presentation of the state of the art of mechatronic systems reliability estimation methods, we propose a original approach by representing multi domain interactions by influential factors in the dysfunctional modeled by Dynamic Bayesian Networks. A case study demonstrates the interest of the proposed approach

Evaluation of the mechatronic systems reliability under parametric uncertainties

The main research intent of this paper is to evaluate the predicted reliability of mechatronic system, with take into account the epistemic uncertainties, The work reported here presents a new methodology based on integrating the petri network with the belief functions, in order to create a belief network, and to show how to propagate the parametric uncertainties in reliability models, Some notions of uncertainty related to the reliability systems are presented, subsequently a brief definition of the belief function and its application in reliability studies are detailed and how we integrate it in petri network. To take into account the interactive aspect of mechatronic systems, we introduce the uncertainties associated to this interaction, by implementing the new method proposed by using belief network. Secondly, we study the propagation of these interaction uncertainties in system reliability. Finally, in regard to applicate the methodology, an industrial example "intelligent actuator" is developed

On the effect of stiffness/softness and morphology of interphase phase on the effective elastic properties of three-phase composite material

In the present study, Composite material consisting of an elastic homogeneous isotropic matrix in which are embedded coated elastic isotropic inclusions, widely used in many applications is investigate by homogenization approach coupled to the finite elements method. A finite element model is proposed to predict the Young and Shear modulus of the three-phase composite containing spherical inclusions surrounded by a spherical or ellipsoid interphase layer. Three cases of particles volume fractions and interphase was considered with addition of two interphase morphology. Young modulus of interphase region was varied from soft to hard than the matrix properties. We note that interphase morphology and properties plays an important role in the elastic properties of composite with increasing the volume fraction of inclusions and interphase. The results were compared to the first order bounds Voigt and Reuss, and the mean field homogenization techniques. A sensitive study of the effect of mesh density on the results of the von Mises stresses and elastic properties has been made

Le Bassin de Skoura-Tazouta (Moyen Atlas, Maroc): Un Exemple de Paléo-Barrage D’âge NéogèneQuaternaire d’origine Tectonique et à Remplissage Fluvio-Lacustre et Travertineux

The Tazouta-Skoura subsidiary basin, located in the folded Middle Atlas, corresponds to a collapsed zone with multiphase tectonics in the Neogene and Quaternary; it is limited to the west by a branch of the NMAA (North Middle Atlas Accident) and to the south by the Tichoukt ramp. This basin, interpreted by our predecessors as a simple lake basin, is characterized by fluvio-lacustrine and travertine sedimentary deposits. The palaeogeographic and geodynamic studies (geological mapping, lithostratigraphy, … etc) that we have carried out in the Tazouta-Skoura area allowed us to determine the factors responsible for the genesis and evolution of the neogene-quaternary lake basin of Oued Mdaz palaeo-dam. The tectonic and microtectonic analyses of the brittle formations, that affected the neogene and quaternary deposits and their jurassic basis, allowed us to determine the paleo-field of stresses from the valesian, the miocene, the pliocene until the quaternary age, and to highlight the paleo-geography of the zone in question. These states of tectonic stresses played a key role in the geodynamic, structural and paleogeographic evolution of this basin. The dam wall corresponds to a vallesian N130 normal fault with SW dipping, which inverted the bajocian and bathonian strata to SW. The marly levels of these layers, that have a thickness exceeding tens of meters, constitute an impermeable obstacle which blocked the flow of the surface and infiltration water. The lake of the paleo-dam contains a vallesian clay and carbonnate lacustrine deposits. These deposits are surmounted by marine marls from the upper miocene, fluvial Skoura puddings and lake lime-stones of the pliocene age, as well as quaternary fluvio-lacustrine and travertine deposits. This basin is structured by several families of faults, notably NW-SE, ENE-WSW, NE-SW and N-S. The most recent faults correspond to mid-upper quaternary N 170 normal faults. The normal movements of these sub-meridian faults is responsible for elevation of the Douar Ait Chaib plateau, the dislocation of the natural wall of the paleodam of paleo-Mdaz, and eventually the very fast emptying of the lake. This last phenomenon resulted in fast erosion which left hummocks with horizontal surface (Garas). Le bassin subsidient de Tazouta-Sakoura, situé dans le Moyen Atlas plissé, correspond à une zone effondrée à tectonique polyphasée au Néogène et au Quaternaire, il est limité à l’ouest par une branche de l’ANMA (Accident Nord Moyen Atlasique) et au sud par la rampe de Tichoukt. Ce bassin est interprété par nos prédécesseurs comme un bassin lacustre au sens large et à remplissage sédimentaire fluvio-lacustre et travertineux. Les études paléogéographique et géodynamique (cartographie géologique, lithostratigraphie,…) que nous avons effectuées dans la zone de TazoutaSkoura nous ont permis de déterminer les facteurs responsables de la genèse et de l’évolution de ce bassin lacustre en paléo-barrage de Oued Mdaz d’âge néogène-quaternaire. Les analyses tectoniques et microtectoniques des structures cassantes affectant les dépôts néogènes, quaternaires et leur substratum jurassique, nous ont permis de déterminer les paléo-champs de contraintes d’âge vallésien, miocène supérieur, pliocène et quaternaire. Ces états de contraintes tectoniques ont joué un rôle primordial dans l’évolution géodynamique, structurale et paléogéographique de ce bassin. Le mur du barrage correspond à une faille normale N130 à pendage SW d’âge vallésien, qui a basculé les couches bajociennes et bathoniennes vers le SW. Les niveaux marneux de ces couches constituent un obstacle imperméable qui a bloqué les écoulements des eaux de surface et d’infiltration. Le lac du paléo-barrage a connu une sédimentation lacustre de nature argileuse et carbonatée au Vallésien. Ces dépôts sont surmontés par les marnes d’origine marine du Miocène supérieur, les poudingues de Skoura d’origine fluviatile et les calcaires lacustres du Pliocène, et par les dépôts fluvio-lacustres et travertineux du Quaternaire. L’ensemble est structuré par plusieurs familles de failles : NW-SE, ENE-WSW, NE-SW et N-S. Les failles les plus récentes correspondent aux failles normales de direction moyenne N170 d’âge quaternaire moyen-récent. Le jeu normal de ces failles subméridiennes a provoqué d’une part la surélévation du plateau du Douar Ait Chaib, et d’autre part la dislocation du mur naturel du paléo-barrage sur le paléo-Mdaz et la vidange très rapide du lac. Ce dernier phénomène a provoqué une érosion rapide qui a laissé des buttes témoins à surface horizontale (Garas)

La Qualité de l'Immatriculation Foncière, la Confiance des Investisseurs et l'Impact sur l'Investissement au Maroc : Cas de la région Tanger-Tétoaun-Al Hoceima

Land registration is an essential process in the investment field, as it secures ownership of land and property rights for investors. A clear, transparent and efficient land registration procedure can play a crucial role in encouraging investment in a region. This article presents the results of a study designed to examine the correlation between the quality of land registration, investor confidence and economic commitment in the Tangier-Tetouan-Al Hoceima region. To achieve this objective, a research methodology based on Pearson correlation was used. The study used an online survey method via Google Forms to interview a sample of 520 investors in the region, focusing on variables related to the quality of land registration, investor confidence and economic commitment. The results obtained from this analysis will provide valuable information on the relationships between these variables and contribute to a better understanding of the factors influencing investment decisions in the land context.We begin with a literature review, then operationalize the concepts and draw up the various hypotheses that form our model, before presenting a summary of the results obtained. In conclusion, this study highlights the crucial importance of land registration quality in attracting investors, boosting their confidence and fostering their economic commitment in the Tangier-Tetouan-Al Hoceima region. These results enrich the literature on the link between the quality of the land tenure system and economic investment, offering interesting avenues for future research in this field.   Keywords : land registration, investors, property rights, transparency, mortgage financing, investment decision. JEL Classification : R52 Paper Type : Emprical reserach.L'immatriculation foncière est un processus essentiel dans le domaine de l'investissement, car elle permet de garantir la propriété des biens fonciers et de sécuriser les droits de propriété des investisseurs. Une procédure d'immatriculation foncière claire, transparente et efficace peut jouer un rôle crucial dans l'encouragement des investissements dans une région. Cet article présente les résultats d'une étude visant à examiner la corrélation entre la qualité de l’immatriculation foncière, la confiance des investisseurs et leur engagement économique dans la région de Tanger-Tétouan-Al Hoceima. Pour atteindre cet objectif, une méthodologie de recherche basée sur la corrélation de Pearson a été utilisée. L’étude a utilisé une méthode d'enquête en ligne via Google Forms pour interroger un échantillon de 520 investisseurs dans la région, se concentrant sur les variables liées à la qualité de l'immatriculation foncière, la confiance des investisseurs et leur engagement économique. Les résultats obtenus à partir de cette analyse fourniront des informations précieuses sur les relations entre ces variables et contribueront à une meilleure compréhension des facteurs influençant les décisions d'investissement dans le contexte foncier. Au début, nous commençons par une revue de littérature, puis nous allons opérationnaliser les concepts et dresser les différentes hypothèses qui forment notre modèle avant d’exposer un résumé des résultats obtenus. En conclusion, cette étude souligne l'importance cruciale de la qualité de l’immatriculation foncière pour attirer les investisseurs, renforcer leur confiance et favoriser leur engagement économique dans la région de Tanger-Tétouan-Al Hoceima. Ces résultats enrichissent la littérature sur le lien entre la qualité du système foncier et l'investissement économique, offrant des pistes intéressantes pour des recherches futures dans ce domaine.   Mots clés: immatriculation foncière, investisseurs, droits de propriété, transparence, financement hypothécaire, decision d'investissement. Classification JEL: R52 Paper type: Recherche empirique