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Kidari A.,University of Limerick | Kidari A.,CEA Marcoule Nuclear Site | Mercier C.,University of Valenciennes and HainautCambresis | Leriche A.,University of Valenciennes and HainautCambresis | And 3 more authors.
Materials Letters | Year: 2012

Na-Li-Si-Al-P-O-N glasses have been prepared by nitridation of a pre-synthesized Na 2O-Li 2O-SiO 2-P 2O 5-Al 2O 3 glass under anhydrous ammonia. Nitrogen for oxygen substitution increases the network connectivity leading to increases in microhardness and glass transition temperature. Raman and 31P MAS-NMR spectroscopy indicate sequential nitridation reactions forming PO 3N and PO 2N 2 species. The data collected so far show no evidence of N/O substitutions in the silicate sub-network. © 2012 Elsevier B.V. All rights reserved.

Maj A.M.,University of Lille Nord de France | Maj A.M.,Ecole Nationale Superieure de Chimie de Lille | Suisse I.,University of Lille Nord de France | Suisse I.,University Lille1 science et Technologies | And 7 more authors.
Tetrahedron Letters | Year: 2012

The asymmetric hydrogenation of a new series of 2-functionalized quinolines has been developed in the presence of in situ generated catalysts obtained from [Ir(cod)Cl] 2/(R)-bisphosphine/I 2 combinations. The enantioselectivity levels were as high as 84-94% ee for the synthesis of 1,2,3,4-tetrahydroquinolines. © 2012 Elsevier B.V. All rights reserved.

Suryatriyastuti M.E.,University Lille1 science et Technologies | Mroueh H.,University Lille1 science et Technologies | Burlon S.,Institute francais des science et technologies des transports
Computers and Geotechnics | Year: 2014

Unsatisfactory understanding of thermally induced axial stress and mobilized shaft friction in the thermo-active piles has led to a cautious and conservative design of such piles. Despite the fact that the number of construction works using this type of piles has been rapidly increasing since the last 20. years and none of them witnessed any structural damage, the question that still remains is how to overcome the cyclic thermal effects in such piles to optimize the design method. This paper presents a soil-pile interaction design method of an axially loaded thermo-active pile based on a load transfer approach by introducing a proposed t-z cyclic function. The proposed t-z function comprises a cyclic hardening/softening mechanism which is able to count the degradation of the soil-pile capacity during two-way cyclic thermal loading in the thermo-active pile. The proposed t-z function is then compared to a constitutive law of soil-pile interface behavior under cyclic loading, the Modjoin law. Afterwards, numerical analyses of a thermo-active pile located in cohesionless soil are conducted using the two cyclic laws in order to comprehend the response of such pile under combined mechanical and cyclic thermal loads. The behaviors of the pile resulting from the two laws show a good agreement in rendering the cyclic degradation effects. At last, the results permit us to estimate the change in axial stress and shaft friction induced by temperature variations that should be taken into account in the geotechnical design of the thermo-active pile. © 2013 Elsevier Ltd.

Barj M.,University Lille1 science et Technologies | Mykaylo O.A.,Uzhgorod National University | Kaynts D.I.,Uzhgorod National University | Gorina O.V.,Ukrainian Academy of Sciences | And 2 more authors.
Journal of Non-Crystalline Solids | Year: 2011

The main aim of the study presented in this paper is the investigation of the structure of (As2S3)100-x(SbSI)x and (As2Se3)100-x(SbSI)x (0 ≤ × ≤ 40) glasses by Raman spectroscopy and X-ray methods, also the nature of the crystalline inclusions which arise up in their matrix at heat treatment. We have found that in conditions of continuous heating in the interval "glassforming temperature-crystallization temperature" a crystallization with predominant mechanism of stable phase SbSI separation is taking place. The formation mechanism of crystalline inclusions of antimony sulphoiodide in glass matrix is discussed in the light of our results. It was established that all investigated glasses have a nano-heterogeneous structure. © 2010 Elsevier B.V. All rights reserved.

Chaaban F.,Laue Langevin Institute | Darwishe H.,Laue Langevin Institute | Louche B.,University of Artois | Battiau-Queney Y.,University Lille1 science et Technologies | And 3 more authors.
Environmental Earth Sciences | Year: 2012

The use of geographic information system (GIS) minimizes the effort and improves the efficiency of numerical models. The GIS provides a platform for high capacity collection, management, manipulation, analysis, modeling and display of spatial data. The conceptual model is created using GIS objects including points, arcs and polygons so that it can accurately represent real world condition. According to the research problem, the geographical model is based on Hypergraph Based Data Structure method, and a conceptual data model has been created from which a physical data model was elaborated in ArcGIS9. 3 platform. The groundwater modeling system (GMS) provides a powerful tool for hydrodynamics modeling and it is able to solve complex problems such as the groundwater flow and seawater intrusion. The sand-dune system of Hardelot-Plage (North of France) suffers from a lack of well-developed foredune. This problem is linked to the almost constant saturation of beach sand which is the potential source of dune nourishment. In the south of Hardelot, the coastline is slowly, but constantly retreating. To remedy this situation, a coupling between a GIS and GMS was adopted, in order to find the possible scenarios which could lower the piezometric surface in the concerned area and allow dune nourishment again. The GMS used supports the Modflow-2000 code. A direct approach to designing Modflow finite difference model is tedious and less intuitive, specifically for complex boundary and initial conditions. Therefore, a Modflow model can be developed either using a grid or conceptual model approach. The preparation of input data modeling is tedious and takes a long time. The model created in GMS was calibrated against the historical and observed water level data for 1995-2006. Then a hydrodispersive model (MT3d code in GMS) was launched for evaluating sea-water intrusion. The model was run to generate groundwater and salt concentration scenario during pumping tests. © 2011 Springer-Verlag.

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