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International audience; Aucoumea klaineana Pierre (okoumé) is a tropical hardwood used in the timber industry in the Congo area to produce veneers and plywood. This paper described the utilization of sapwood co-products from this industry according to a biorefinery approach to generate both bioethanol and lignin. A batch Steam Explosion (SE) was used as a pretreatment after acid impregnation (H 2 SO 4 0.25 % or 0.50 % w/w) at various pressure (8-19 MPa) and residence times (2.5-7.5 min). The impact of the process was examined at the molecular and parietal scales. The pulp composition was examined in terms of lignin, glucose and xylose content, cellulose crystallinity (CrI %) and degree of polymerization (DP). The conditions of 2 high pretreatment severity led to an almost total xylans removal (residual xylans < 2 %), to a strong decrease of cellulose DP and to a lignin fragmentation and relocation increasing its extractability with ethanol as solvent. At the parietal scale, the effect of the pretreatment on wood cell wall was analyzed by optical microscopy after dyeing, fluorescence microscopy and scanning electron microscopy. Enzymatic hydrolysis of the cellulosic pulps was experimented using commercial cellulase from T. Reesei. A SE pretreated wood produced at 210°C during 5 min with an impregnation with 0.25 w/w% acid resulted in a glucose yield > 80 % with an excellent fermentability into ethanol by S. Cerevisiae. Using these operating conditions, one ton of okoumé sapwood could produce 112 kg of ethanol and 82 kg of high purity lignin.

International audience; This article shows a comparison of rigid image registration methods of monomodal and multimodal images. These methods are applied on different images of oak wood pieces. The work presented in this article is a part of a complete vision system which aims to analyze the visual and physico-chemical aspect of oak wood piece surface. In this context, a multi-sensor acquisition using a multimodal imagery platform is performed. The acquired images are not superimposable due to the rigid deformations resulting from the use of different sensor scanners and the presence of imperfections during the image acquisition process. This leads to consider image registration as a preprocessing step. The efficiency of the registration method depends on the deformation itself and the type of image to be registered. That is why we propose a comparison of different built-in and extended MATLAB registration methods, based on cross-correlation, phase correlation, mutual information and alignment of geometric primitives. The registration evaluation of the different methods is done by using quantitative measure of image alignment, visual inspection and computational time. Finally, the choice of the most adapted image registration methods, based on the existing differences between the acquired images, in terms of type of deformations and image modality, is discussed.

International audience

This work aims at demonstrating the possibility of producing 2-butanol from lignocellulosic biomass through a new thermochemical approach. The production of biobutanol was carried out using different lignocellulosic feedstock through a 3-step process: first the whole lignocellulosic biomass is hydrolyzed under acid catalyst to produce levulinates, then the levulinates go through decarboxylation to produce 2-butanone which is, in a final step, reduced to produce of 2-butanol. The experimental conditions for the first two steps of the process were optimized using the response surface methodology (RSM). The latter could represent an opportunity for the production of economical second-generation butanol without having to go through the classical pathway requiring the production of sugar prior to microbial conversion. The authors are grateful for the financial support to MITACS (Grant number ITO3931) and for the grant to the Natural Sciences and Engineering Research Council of Canada (NSERC, Grant number EGP 487206-15).

International audience; The main compounds of plant biomass, i.e., cellulose, lignin and hemicellulose, were submitted to hydrothermal carbonisation (HTC) in ranges of temperature and time of 140-240ºC and 0.5-24 h, respectively. Those parameters were combined into a single one, the severity factor, and its effect on hydrochar yield on the one hand, and on pH, yield and composition of the liquid fraction on the other hand, was investigated in depth. The production of furanic and phenolic compounds was correlated with both severity and pH. The kinetics of furfural (FU) and 5-hydroxymethylfurfural (5-HMF) production and consumption were also investigated and modelled, and the results were compared to those reported in the literature. The production of nine phenolic compounds from lignin HTC was also considered.

Poster session: P5 - CIPA2013-191; International audience; Building energetic performances strongly depend on the thermal insulation. However the performance of the insulation materials tends to decrease over time which necessitates the continuous monitoring of the building in order to detect and repair the anomalous zones. In this paper, it is proposed to couple 2D infrared images representing the surface temperature of the building with 3D point clouds acquired with Terrestrial Laser Scanner (TLS) resulting in a semi-automatic approach allowing the texturation of TLS data with infrared image of buildings. A contour-based algorithm is proposed whose main features are : 1) the extraction of high level primitive is not required 2) the use of projective transform allows to handle perspective effects 3) a point matching refinement procedure allows to cope with approximate control point selection. The procedure is applied to test modules aiming at investigating the thermal properties of material.

A total of 868 historical wooden archival boxes from the municipal and regional archives as well as from the French National Archives were studied by archaeodendrometrical techniques. The boxes were shown not to be airtight and to emit moderate concentrations of volatile organic compounds. The interactions between their content and the indoor environment were studied to investigate whether the emitted volatile organic compounds can impact the stability of the cellulosic documents and metallic artefacts they contain. Regardless of their age, results have shown that the boxes do not seem to represent a particular risk for cellulosic materials nor metallic artefacts., Les interactions entre d’anciennes boîtes en bois utilisées pour le conditionnement des archives, leur environnement et leur contenu ont été étudiées. L’objectif était de déterminer si les composés organiques volatils (COV) émis par les boîtes peuvent contribuer à diminuer la stabilité des documents cellulosiques ou des objets métalliques contenus. 288 boîtes provenant d’archives municipales et départementales ainsi que des Archives nationales de France ont été datées par dendrochronologie entre le XIVe et le XXe siècle. Ces boîtes ne sont pas étanches à l’air, les faibles concentrations en COV et leur distribution qualitative montrent que, quel que soit leur âge, elles ne semblent pas présenter de risque particulier pour les objets cellulosiques ou métalliques.

Groundwater modelling has become a major step for decision support in integrated water resource management, but groundwater models require accurate and spatially distributed data to provide reliable results. Hydrogeological modelling of these data can be implemented with physically based models (i.e. MODFLOW, MT3D…). Other approaches that are simpler to implement may be a good substitute for these numerical approaches. This is the case of probabilistic approaches and especially the statistical approach neural networks. The proposed method (coupling GIS/ANN) is especially suitable for the problem of large-scale and long-term simulation. It has been applied in the spatial prediction of nitrates in the chalk aquifer in Bethune (North of France). This confined chalk aquifer in its northern part provides natural denitrification and ensures a good drinking water quality, while in its southern part this aquifer is facing a high level of nitrate concentrations far above the European Nitrates Directive standard. A good groundwater management of this ecosystems service is therefore of great importance for regional water management. Thus, the spatial distribution of nitrate concentration obtained by GIS/ANN coupling model was compared with the results obtained from the numerical modelling (MT3D) and validated by the real measurements. ANN modelling seems to be more realistic than MT3D modelling both for 2003 and 2004. This is true for both of the nitrate concentrations and their difference. So, ANN modelling’s spatially distributed difference with observed data ranges from − 3.67 to + 1.24 mg/l in 2003 and − 10.8 to + 6.51 mg/l in 2004, whereas for the MT3D model, this difference ranges from − 11.5 to + 17.9 mg/l in 2003 and − 9.91 to + 16.9 mg/l in 2004. The satisfactory results of the ANN model allowed to launch prospective simulations for 2025 under two groundwater recharge scenarios: a deficit year (150 mm/year) and a rainy year (500 mm/year) show an expansion of the exploitable zone ([NO3–]

International audience; The preparation of antibacterial UV powder coatings dedicated to wood based panels is described in the present study. Two experimental methods were investigated: the generation of silver nanoparticles during the polymerization of UV powders and the introduction of a silver modified beidellite within UV powder formulations. While the first method leads to some nanoparticle aggregation, this phenomenon was avoided with the second approach. Antibacterial activity was thus ensured by the presence of beidellite modified with silver cations. XRD, X-ray fluorescence, SEM/EDX and TEM analyses allowed a complete characterization of the Ag-beidellite before its incorporation within UV powder formulations. Real-time-FTIR spectroscopy fitted with an environmental cell was used to monitor the reactivity of UV powder formulations under UV light and temperature control. Resulting coatings were finally characterized by UV spectroscopy, DMA in tension mode, XRD, TEM and antimicrobial analyses. It was shown that the fully cured and homogeneous coatings exhibit high thermomechanical properties and antibacterial activity.

International audience; The penetration depth into wood structure by different wood finishes (solvent-borne, waterborne or powder) was assessed using a non-destructive analysis method, that is, X-ray tomography. The coating thickness was also evaluated. The results obtained from the image analysis by two specific softwares, namely VGStudio MAX(A (R)) and ImageJ(A (R)), are compared and discussed by taking into account the chemical properties and anatomy of wood materials and the nature of finishes. The degree of coating penetration is mainly determined by its ability to flow into capillaries, and it was observed that resin type, solid matter content and drying method influence this ability.

Chaaban, F.; Darwishe, H.; Battiau-Queney, Y.; Louche, B.; Masson, E.; El Khattabi, J., and Carlier, E., 2012. Using ArcGIS® Modelbuilder and aerial photographs to measure coastline retreat and advance: North of France. Coastal areas are naturally dynamic with changes occurring over periods of time. When the shoreline moves landward, coastal erosion becomes a serious problem, and the rate of change has to be calculated. Coastline retreat is one of the best indicators of coastal erosion. Here, the geographic information systems (GIS) platform (ArcGIS® 9.3.1; Esri software) is used to study the long-term (last 59 years) shoreline change in the area of Hardelot-Plage and Sainte Cecile–Plage (a north–south 14-km-long beach), in northern France. The primary aim of this study was to develop a methodology for calculating shoreline change using ArcGIS Modelbuilder and aerial photographs. Changes in 14 coastlines over the course of 59 years (from 1946 to 2005) were digitized and represented in ArcGIS 9.3....

Colloque avec actes et comité de lecture. Internationale.; International audience; This paper aims to present the influence of several constructive options on the vibro-acoustic behavior of a wooden lightweight structure. The experiemental protocol, which was optimised and described in an preceeding paper, allows us to quantify the influence of these constructive options in terms of acoustic level and isolation, eigenfrequencies and vibration mode shapes of the different parts of the structure. The results of this work are coherent and confirmed that the experimental test protocol is functional and repeatable.

National audience; Cet article présente la démarche mise en oeuvre dans le projet collaboratif ANR Hygrobat, qui vise à donner des outils pour quantifier de manière fiable l'impact des transferts de masse sur les transferts de chaleur dans les parois de bâtiments comprenant des matériaux fortement hygroscopiques. Les matériaux sélectionnés dans ce projets (fibre de bois, bois massif, OSB) ont été soigneusement caractérisés. Leurs propriétés hygrothermiques ont été mesurées en laboratoire, puis ils ont été mis en oeuvre dans des parois, soumises à des conditions aux limites de variées. L'originalité de l'étude réside dans : (i) la démarche " pas à pas " de complexité croissante, partant des caractérisations d'un seul matériau en conditions stationnaires, jusqu'aux mesures sur une paroi multicouche en climat réel ; (ii) les vérifications croisées de mesures expérimentales, qui sont effectuées dans deux des laboratoires partenaires du projet, parfois sur des dispositifs différents ; (iii) association des benchmarks expérimentaux et numériques. MOTS-CLÉS : transferts couplés de chaleur et de masse, matériaux hygroscopiques, benchmarks

International audience; The health problems amongst musical instrument makers working on the White mulberry (Morus alba), lead to investigate the toxicity potential of wood extractives. Five solvents of different polarity and two methods of extractions were used to ensure a thorough, clear and classified compound removal. The compounds were identified using qualitative GC-mass and the toxicity were determined by studying their effect on termite survival (Reticulitermes flavipes). The results indicated the presence of different compound categories like phenols, higher hydrocarbons, fatty acids, sterols and aromatic components in the extractives. These compounds were not removable by just one solvent and the order of removal was polarity related. The extractives were found toxic towards termites. Resorcinol, which corresponded to the highest proportion of peaks in the GC-mass spectra, has been assigned as the possible compound responsible for the allergic reactions by the artisans.

International audience; The purpose of this work was to determine the main factors influencing the phenolic content of bark during acid hydrolysis. The optimization of polysaccharides hydrolysis was done by response surface methodology. The hydrolysis was performed under atmospheric pressure in an aqueous solution of sulfuric acid. An experimental design was applied to analyze the effects of the reaction time (5 to 24 hours), acid concentration (3 to 20%), and solid/liquid ratio (1/10 to 1/5) on the weight loss, lignin content, holocellulose content, and sugar yield for the hydrolysis. The pretreated bark had a high lignin content of 60% resulting from hemicelluloses hydrolysis and phenolic compound condensation.

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.

National audience