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International audience; In the indoor environment, the growth of microorganisms on building materials leads to the deterioration of both the materials and indoor air quality. As bio-based building materials usually contain cellulose or derivatives, they are likely to be much more sensitive to such degradation. Using glycerol esters could be a way to protect bio-based materials from microorganisms. Indeed, previous studies have highlighted the significant antimicrobial effect of glycerol esters and they are commonly used in the food industry as antimicrobial agents. In addition, as glycerol is a valuable by-product of the agroindustry, it would be an eco-friendly alternative, consistent with human health, to the classic ways of protecting bio-based materials against microorganisms. This study is part of a project that aims to (a) assess the hygrothermal performances and reaction to fire of sunflower panels and (b) study the antimicrobial efficiency of glycerol esters for the protection of such bio-based materials from microbial proliferation. The materials presented physical, thermal and hygroscopic properties similar to those of bio-based materials such as wood or hemp, encouraging their use as insulation materials. In addition, the glycerol esters showed significant antimicrobial effects but also a susceptibility to flammability. One unanticipated finding was that the untreated insulation material made of sunflower pith was classified as non-flammable.

International audience; The influence of biomass macromolecular composition on its behaviour in torrefaction was statistically assessed through Principal Component Analysis (PCA), both in terms of solid conversion kinetics and volatile species released, in function of the operating conditions. The experimental data obtained in the torrefaction of 14 woody and agricultural biomass samples at lab-scale was analysed. Main biomass macromolecular composition on cellulose, hemicelluloses and lignin was shown to acceptably represent biomass diversity, which can be complemented by the extractives and ash content. Similitudes were found in deciduous and coniferous wood families, respectively, while agricultural and herbaceous crops were shown as more heterogeneous, both in terms of characterization and behaviour in torrefaction. Cellulose, hemicelluloses and lignin content strongly influenced solid and volatile species yields in torrefaction, while biomass family exhibited a lower impact. Ash content in potassium, phosphorous and silicon did not show any influence on the extent of solid degradation through torrefaction. A lower variability was found in solid degradation profiles from woods, while agricultural crop behaviour was more heterogeneous. Different volatile species were released from biomass samples from the same family. Furthermore, different production profiles were found for volatile species chemically close, except for deciduous wood. These results indicate that, when modelling biomass torrefaction, solid mass loss can be represented by an exemplar of deciduous and coniferous wood, while several species would be required for the agricultural family. The variability of the volatile species release would require the consideration of several volatile species and several biomass samples per family.

International audience; A new torrefaction model was proposed for predicting solid mass loss in torrefaction as a function of biomass main macromolecular composition and type, as well as on the operating conditions. To do this, solid degradation kinetics were modelled following a 2-successive reaction scheme for each macro-compound and the additive modelling approach through biomass macromolecular component behavior in torrefaction proposed by Nocquet et al. (2014). The use of extracted fractions from different woody and agricultural biomass species (ash-wood, beech, miscanthus, pine and wheat straw) instead of commercial compounds increased the accuracy of the prediction of solid kinetics in biomass torrefaction. The validation of the proposed model with 9 raw biomasses in torrefaction showed an accurate prediction for woods, while the prediction for agricultural biomasses was acceptable.

International audience; Prediction of durability of wood product is a major challenge and an important goal for furniture industry. Numerical simulation based on approximation methods such as the finite element method (FEM) is an efficient and powerful tool to address this challenge while avoiding expensive experimental testing campaigns. Nevertheless, the strong heterogeneity of wood-based materials, the specific geometrical characteristics of wood-based structures (such as furniture that can often be represented as an assembly of beams, plates and/or shells) and the complex nonlinear 3D local behavior near the connections between structural parts may induce some difficulties in the numerical modeling and virtual testing of furniture for robust design purposes. Especially, when cyclic loading occurs, the behavior of junctions in furniture involves a local permanent strain that increases with the number of cycles and that can lead to an important gap potentially affecting the structural integrity of furniture. In this paper, we present an experimental campaign of cyclic compression tests carried out on spruce specimens. Theses specimens are cut out from a bunk bed and loaded under cyclic compression. The cyclic compression loading applied to the specimens leads to an evolution of the permanent strain during cycles that is modeled using a simple law describing the displacement gap as a function of the number of cycles. Considering the strong dispersion in the mechanical properties of wood-based materials and the variabilities induced by the experimental configuration, a stochastic modeling of the gap is proposed by having recourse to the maximum entropy (MaxEnt) principle in order to take into account the random uncertainties on the experimental setup and between the test specimens. The random mechanical response of a complex corner junction in a bunk bed under cyclic loading is then numerically simulated by using a Monte Carlo numerical simulation method as stochastic solver. This provides independent realizations of the random gap evolution (with respect to the number of cycles) in the bunk bed corner, allowing probabilistic quantities of interest related to the random gap, such as first-and second-order statistical moments (mean value, standard deviation) as well as confidence regions (with a given probability level), to be estimated.

International audience; This paper aims at presenting a digital correlation technique to capture the full-field displacement thanks to a high-speed camera of a full scale structure tested on a shaking table. The challenges are both the measurements at a full scale to visualize damages versus the resolution of pictures and the dynamical loading that requires a large number of pictures. The final goal is a better understanding of the seismic behavior of timber-framed structures with infill to help at modeling such structures and predicting their seismic vulnerability. For this purpose, results of shake table tests carried out on a full-scale one-story timber-framed house filled with stones bonded by an earth based mortar are presented and discussed. DIC full-field measurements allow deriving displacements and accelerations on shear walls as well as lateral forces applied on them. The experimental results presented herein allow analyzing the influence of bracing and might be used to propose optimized aseismic constructions based on cheap technological solutions. These results demonstrate the seismic-resistant behavior of timber-framed structures with infill and constitute a key issue for the promotion of such constructions in developing countries.

ACT; International audience; Using low emissive materials in building is an effective way to reduce indoor concentrations of pollutants such as VOCs. Material emissions are assessed by the ISO 16000-9 standard. This procedure is time-consuming and is not suitable for on-site measurements. This work aimed in assessing an alternative method, DOSEC®-SPME, for simple measurements. To validate it, emissions of 30 materials were characterized by both ISO 16000-9 and DOSEC®-SPME. A first correlation was found between the two methods for formaldehyde emissions of raw materials. This encouraging result allows considering the development of new decision making tools for the selection of healthy building materials.

International audience; Wood furniture is often composed of simple parts that may be modeled as beams or plates. These particularities allow using simplified approaches that reduces the number of degrees of freedom (dof for short) in a finite element simulation of the furniture's behavior. Generally, connections are not taken into account in such simulations but these connections are critical in the failure process of the furniture and it worth studying it precisely. Using a multi-scale approach, this paper introduces a numerical procedure to identify the connection contribution in the furniture's stiffness. Comparing 3D finite element calculations with a Timoshenko's beam calculation on a corner of two wooden parts, we identify the specific behavior of the connection elements (pins, nut, screw… and local 3D effects) to introduce it as a punctual 0D element in the beam code. Two validations of the approach are presented here: (i) a numerical validation by comparing the result of the beam code with a complete 3D finite element simulation on a representative plane structure of wooden furniture; (ii) an experimental validation by managing a global bending test and measuring the displacement field using digital image correlation (DIC for short).

International audience; The objective of this study is to improve evaluations of the future use of biomass sources in Sweden and France by representing the high spatial variations of the supply and cost of biomass sources in energy system models. The proposed methodology considers a high spatial disaggregation of biomass supply sources, as well as detailed biomass cost-supply curves, and is thereby able to account for spatial differences in heterogeneous land qualities, management strategies, and possible adaptation rates. Integrating the methodology into national or regional energy system models will enhance cost-effective evaluations of biomass sources as well as the development of the bioenergy sector. A TIMES energy system model was used to evaluate bioenergy production potential for France and Sweden based on domestic biomass sources and under the assumption that bioenergy production should not be at the expense of domestic food and forestry supply. Results show that by 2050, the biomass sources considered could provide as much as 250PJ of bioenergy in Sweden, and 1470PJ of bioenergy in France. Results further showed that 1st generation biofuels are likely to continue to play a substantial role in the biofuel mix. While 2nd generation biofuel production in Sweden is likely to be low, larger amounts of 2nd generation biofuels could be produced in France. However, the amount and type of 2nd generation biofuel produced in France was found to be highly dependent on the bioenergy demand level.

Short rotation coppices (SRCs) are considered prime candidates for biomass production, yielding good-quality feedstock that is easy to harvest. Besides technical, social and economical aspects, environmental issues are important to take into account when developing SRCs. Here, we evaluated the environmental impacts of delivering 1 GJ of heat from eucalyptus SRC using life cycle assessment (LCA), based on management scenarios involving different rotations lengths, fertilizer input rates, stem densities and harvest methods. Compared to equivalent fossil chains, all eucalyptus scenarios achieved savings of fossil energy and greenhouse gas (GHG) emissions in the 80%-90% range, and had generally lower impacts, except for eutrophication. The 3-year rotation scenario was the most energy and GHG-intensive, while manual felling for the longer rotations resulted in 2-fold larger photochemical ozone impacts compared to the other scenarios. Transportation of wood chips and fertilization were the top two contributors to the impacts, the latter being more important with the shorter rotation lengths due to the evergreen character of eucalyptus. The possibility of including ecosystem carbon dynamics was also investigated, by translating the temporary sequestration of atmospheric CO2 in the above- and below-ground biomass of eucalyptus as CO2 savings using various published equivalence factors. This offset the life-cycle GHG emissions of heat provision from eucalyptus SRCs by 70 to 400%.

Producing hard carbon from lignocellulosic biomass has been the focus of recent studies as a promising source of anode material for Na-ion batteries. Woody biomass is a potential source, but it is already well valorized. Consequently, river driftwood can be an excellent alternative, especially since it is a disturbing waste for dam regulators. It can jeopardize dam safety, damage intake works, and sink in reservoirs, lowering water quality and decreasing reservoir volume. We examine the potential of river driftwood as a source of hard carbon for Na-ion batteries. Hydrothermal carbonization (HTC) was carried out at temperatures between 180 and 220 ◦C as the first step to produce hydrochar followed by an upgrading pyrolysis step at 1400 ◦C under an inert atmosphere to obtain hard carbon. We investigated the effect of HTC operational conditions and driftwood biomass (genera) on hydrochar and hard carbon properties, as well as the latter’s impact on Na-ion batteries. The produced carbon electrodes delivered a reversible capacity of 270–300 mAh⋅g-1 for the first cycle and showed high coulombic efficiencies of 77–83%. We also observed promising cyclability of a maximum 2% loss after 100 cycles. Moreover, results suggest that obtained hard carbon can compete with commercial materials and is capable to supply large battery factories with anode material.

SSCI-VIDE+CDFA+LDJ; International audience; Several lignin samples of varying botanical nature (softwood, hardwood, or annual plants) and extraction procedures (Kraft, Organosolv, or soda) were fully characterized by complementary techniques and engaged in “catalyst-free” depolymerization in air under basic conditions. Treatment of the complex reaction mixture was optimized to ensure reproducibility, careful analyses, and accurate data. After an optimization of the reaction conditions, we were able to recover high amounts of aromatic compounds (up to 19%wt). Additionally, we demonstrated a relation between lignin’s structure, i.e., the accessible phenol moieties and inter-unit linkages, and the yields of aromatic compounds, thus showing the importance of the extraction process to optimize lignin’s potential. This work provides valuable reference for developing further lignin depolymerization under basic media.

International audience; The production of volatile species in torrefaction of cellulose, hemicellulose and lignin extracted from woody and agricultural biomass was quantified as a function of temperature. The novel coupling of TGA to GC/MS through a heated storage loop system allowed sampling volatile species released at 11 different temperatures in a single torrefaction experiment between 200 and 300 °C, at 3 °C.min−1. The results showed that the use of extracted fractions obtained from different biomass samples led to the detection of a higher number of species (23) than in previous studies with commercial compounds, obtaining a higher degree of detail in the characterization of the production of volatile species in torrefaction. Volatile species were generally released in this study from lower temperatures than those previously reported for commercial compounds. This may be due to the better preservation of cellulose, hemicellulose and lignin properties in extracted fractions thanks to the optimized extraction procedure. Volatile species production profiles were assessed based on the formation mechanisms proposed in the literature and the production of polysaccharide-based fractions was shown to be correlated to their sugar composition. Finally, production profiles allow identifying the temperature range to enhance the production of a given volatile species in torrefaction.

International audience; This work assesses the potential of nettle (Urtica dioica L.) fibers produced on contaminated lands for composite applications. The nettles studied in this work grew spontaneously and in a prevalent manner in poplar short rotation coppice planted for the phytomanagement of a land contaminated by traces of metals. Results show that the contaminant contents in nettle bast fibers are low: only traces were measured. It makes it possible to consider this biomass for material use. The measured matter yield is lower than those obtained with traditional fiber crops cultivated in Europe on agricultural lands but the tensile properties of the bast fibers are equal to or better than those of hemp and flax, making spontaneous nettle an interesting supplement to traditional European fiber crops for composite applications

International audience; Fractionated pyrolysis coupled to gas chromatography and mass spectrometry experiments (Py-GC/MS) were carried out on eight woody and agricultural biomasses, including beech, poplar, pine forest residues, Scot Pine bark, reed canary grass, corn cob, grape seed cake and wheat straw. The selected temperature and duration for each fractionated pyrolysis step allowed separating the volatile pyrolysis products in function of their origin from biomass. As a result, carbohydrate derivatives from hemicelluloses were released at earlier fractionated pyrolysis steps, compared to those produced from cellulose degradation. Phenolic derivatives, mainly produced by lignin, were stepwise produced in function of the length and the nature of their side-chain substituents. Protein derivatives were also released in the whole Py-GC/MS temperature range. Macromolecular composition and biomass family were shown to play a crucial role in the thermal degradation of the biomasses of study. Production profiles exhibited resemblances per chemical species between deciduous and coniferous woods, while they appear to be more heterogeneous for agricultural biomasses. Herbaceous crops showed an intermediate behaviour between woods and agricultural biomasses.

International audience; To make intensive bioenergy poplar plantations attractive on an economic and environmental point of view, their sustainable resource management is mandatory. These plantations are indeed often installed on marginal lands to avoid competition with food agriculture and large amounts of nutrients are repeatedly exported in the young harvested biomass. Besides the application of organic residues to reclaim impoverished soils, the use of species or genotypes efficiently using nutrients, and especially nitrogen, is also a way to slow down fertility losses in short-rotation poplar plantations. Our goal in the present study was to document the genotypic variability available in terms of yield, nitrogen-use efficiency (NUE), and nitrogen export rate, the links between these traits, and their plasticity in response to contrasting site conditions and during two rotations in a wide set of Populus deltoides × Populus nigra genotypes. A wide range of variation has been highlighted for biomass production, tree dimensions, and nitrogen use and export at both sites, and particularly at the most productive one. Environmental and genotype by environment effects were very strong and the ranking of genotypes was not maintained between the two sites for most studied traits. Because of climatic conditions less contrasted between sites during the second rotation, the differences were less marked than during the first rotation. The most productive and efficient genotypes to use nitrogen were also those responsible for the highest nitrogen exports during harvest. Indeed, although the most productive genotypes had high NUE, their high biomass production resulted in a more important nitrogen export at harvest than the less productive genotypes.

International audience; The behavior of biomass in torrefaction is determined by that of its macromolecular components, as well as by the biomass type. However, up to now, commercial compounds were typically used for modelling biomass torrefaction. This work proposes to assess the behavior of cellulose, hemicelluloses and lignin in torrefaction through extracted fractions directly isolated from woody and agricultural biomasses (ash-wood, beech, miscanthus, pine and wheat straw) thanks to an optimized extraction procedure. The solid kinetics of these extracted fractions were analyzed through thermogravimetric analysis (TGA) in chemical regime conditions (200–300 °C at 3 °C·min−1 followed by 30 min at 300 °C). These experiments highlighted the influence of the biomass type and the sugar composition in the degradation of the polysaccharide fractions in torrefaction, particularly for hemicelluloses. Furthermore, the degree of preservation of the native structure of the macromolecular components, when extracting them from biomass, seems also having an impact their behavior, especially for cellulose. The comparison of the torrefaction solid kinetic profiles of these extracted fractions, dependent on the biomass type, to that of commercial compounds from previous studies suggest that these extracted fractions would be more suitable for biomass torrefaction modelling.

International audience; Fractionated pyrolysis coupled to gas chromatography and mass spectrometry (Py-GC/MS) appears as an interesting analytical tool for elucidating lignocellulosic biomass structure, as it allows the progressive release of chemical fragments representative of biomass macromolecular composition. In this paper the effect of fractionated pyrolysis time (from 5 s to 300 s) on the degradation of lignin and carbohydrates from beech wood was studied at temperatures between 250 °C and 500 °C. Fractionated Py-GC/MS showed that the release temperature of the volatile degradation products varied between the volatile species detected. In addition, the step duration time changed the thermal degradation behavior of lignocellulosic components. Shortening the constant step duration time from 300 s to 5 s shifted the maximum weight loss to the higher temperatures. The result was opposite at long step duration times. Time optimization at each pyrolysis temperature (250 °C, 40 s; 300 °C, 30 s; 350 °C, 25 s; 370 °C, 20 s; 400 °C, 15 s; 450 °C, 10 s; 500 °C, 5 s) enhanced the yield of both lignin and carbohydrate volatile pyrolysis degradation products. In addition, two multiple temperature maxima were shown for some lignin and carbohydrate derivatives. This behavior may be due to the two different pathways of formation and macromolecular origins of compounds in beech wood. At optimized conditions lignin derivatives having a 3-carbon side chain substituent had a maximum at lower temperature than that of lignin derivatives with a 1-carbon side chain substituent. That phenomenon follows the order of primary and secondary pyrolysis reactions. Similar behaviors were observed among the degradation products of hemicelluloses and cellulose. Degradation products of hemicelluloses were mainly released at lower temperatures than those of cellulose derivatives, which illustrates the lower thermal stability of hemicelluloses compared to cellulose.

Background Lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that cleave polysaccharides through an oxidative mechanism. These enzymes are major contributors to the recycling of carbon in nature and are currently used in the biorefinery industry. LPMOs are commonly used in synergy with cellulases to enhance biomass deconstruction. However, there are few examples of the use of monocomponent LPMOs as a tool for cellulose fibrillation. In this work, we took advantage of the LPMO action to facilitate disruption of wood cellulose fibers as a strategy to produce nanofibrillated cellulose (NFC). Results The fungal LPMO from AA9 family (PaLPMO9E) was used in this study as it displays high specificity toward cellulose and its recombinant production in bioreactor is easily upscalable. The treatment of birchwood fibers with PaLPMO9E resulted in the release of a mixture of C1-oxidized oligosaccharides without any apparent modification in fiber morphology and dimensions. The subsequent mechanical shearing disintegrated the LPMO-pretreated samples yielding nanoscale cellulose elements. Their gel-like aspect and nanometric dimensions demonstrated that LPMOs disrupt the cellulose structure and facilitate the production of NFC. Conclusions This study demonstrates the potential use of LPMOs as a pretreatment in the NFC production process. LPMOs weaken fiber cohesion and facilitate fiber disruption while maintaining the crystallinity of cellulose. Electronic supplementary material The online version of this article (10.1186/s13068-019-1501-0) contains supplementary material, which is available to authorized users.

International audience; Wood recycling is common practice in most countries. Currently, recovered wood is used for relatively low value uses including energy generation, particleboard manufacture, animal beddings and landscape uses. This paper gives an overview of two research projects that aim to generate high-value products from recovered wood and thereby encourage even higher rates of wood recycling. One project is concerned with the extraction of nano-crystalline cellulose from waste MDF and the other produces laminated beams from recovered wood.

International audience; This work aims at designing functional biomaterials through selective chemical modification of xylan from beechwood. Acidic hydrolysis of xylan leaded to well-defined oligomers with an average of six xylose units per chain and with an aldehyde group at the reductive end. Reductive amination was performed on this aldehyde end-group to introduce an azide reactive group. 'Click chemistry' was then applied to couple these hydrophilic xylans moieties with different hydrophobic fatty acid methyl esters that were previously functionalized with complementary alkyne functions. The resulting amphiphilic bio-based conjugates were then self-assembled using three different methods, namely direct solubilization, thin-film rehydration/extrusion and microfluidics. Well -defined micelles and vesicles were obtained and their high loading capacity with propiconazole as an antifungal active molecule was shown. The resulting vesicles loaded with propiconazole in a microfluidic process, proved to significantly improve the antifungal activity of propiconazole, demonstrating the high potential of such xylan-based amphiphiles.

The purpose of this study was to design new biomaterials based on functionalized xylan derivatives. In one approach, 4-O-methylglucuronoxylan (MGX) of beechwood was oxidized by sodium periodate (NaIO4). A ratio of 0.2 NaIO4/xylose leads to a degree of oxidation of 0.15 with 75% yield. Then, the oxidized MGX aldehyde was submitted to reductive amination reaction with benzylamine, and as a result, the xylan backbone was effectively grafted with benzyl groups with a degree of substitution of 0.11. In another approach, controlled sulfuric acidic hydrolysis of MGX was performed to get well-defined xylooligosaccharides (XOS). Then, the reductive amination reaction of the XOS aldehyde functions was performed with allylamine or 2-aminoethylazide to graft the chain ends with an allyl or an azide function, respectively. The proposed methods can open a route to the design of new functional biomaterials.

Herein, we report on the preparation of novel cellulose-PEG biohybrid papers with wet strength properties. The biohybrid paper sheets are obtained using a two-step procedure where ω- or α, ω-azide functionalized PEG chains are anchored onto alkyne-functionalized wood fibers through CuAAC ligation in mild and aqueous conditions. The incorporation of the PEG grafts mostly occurs at the periphery of the cellulose fibers and degrees of substitution up to 0.028 are obtained. The presence of PEG grafts significantly increases the tensile, burst and tear strength properties in the wet state, the reinforcement being more pronounced for fibers grafted with α,ω-azide PEG. This reinforcement is consistent with a relatively sparse hetero-crosslink reaction creating inter-fiber covalent bonds and forming a cellulose network within the cell wall.

Nowadays, musculoskeletal disorders (MD) account for 80% of professional pathologies (INRS 2008).MD contains the peri-articular pathologies that affect muscles, articulations and nerves (INRS 2008)...

International audience; The seismic performance of timber-framed structures filled with stones and earth mortar has been analyzed by introducing the structural subscales (cell, wall, house) at which monotonic and cyclic loadings were considered. This article aims to present the dynamic behavior of a house as determined through shaking table tests. Based on this experimental multiscale analysis, this paper confirms that timbered masonry structures offer effective seismic resistance; moreover, such a comprehensive analysis helps enhance understanding of the seismic-resistant behavior of timber-framed structures with infill. This paper also aids ongoing development of a numerical tool intended to predict the seismic-resistant behavior of this type of structure.

International audience; This study proposes a model using data from a scanner (X-ray and grain angle measurements) to perform strength grading. The research also includes global measurements of modulus of elasticity (obtained by vibrations and ultrasound methods), static bending stiffness and bending strength of 805 boards of Douglas fir and 437 boards of spruce. This model can be used in an industrial context since it requires low computational time. The results of this study show that the developed model gives better results than the global non-destructive measurements of the elastic modulus commonly used in the industry. It also shows that this improvement is particularly higher in the case of Douglas fir than for spruce. The comparison has been made on both the quality of the mechanical properties assessment and on the improvement of the grading process according to the European standards by using different index.

Made available in DSpace on 2018-12-11T17:08:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-12-01 The restoration of deforested or degraded areas can contribute to biodiversity conservation and global resilience given the current and projected impacts of climate change. In recent years, a robust array of ecological restoration frameworks have been generated to address restoration challenges at large scales in different ecosystems around the world. Unfortunately, the costs associated with restoration at such scales greatly challenges the implementation of such frameworks. We used landscape ecology principles with multicriteria optimization of landscape resilience and agricultural productivity as a way to mitigate the trade-offs between production and restoration. We used the Cerrado biome in Mato Grosso do Sul State, Brazil, as a case study to apply our framework. We compared three scenarios: minimal legal compliance (MLC); selection by ecological resilience (SER); and selection by restoration cost (SRC). Our results show that increasing the restoration target from MLC (25%) to SER (30%) means moving from 968,316 to 1592 million hectares, which can represent a huge opportunity cost for agricultural lands. However, because costs and resilience are not homogeneously distributed throughout landscapes, we can select areas of intermediate ecological resilience and low cost, for the same restoration area target. This process can reduce potential conflicts and make restoration a more viable process. Our results also reveal some areas that can be particularly important for reconciling agriculture and landscape restoration. Those areas combined high and intermediate resilience and an above average profitability. This could mean that increasing restoration in this area could be very expensive, assuming that our proxy roughly represents the restoration implementation cost. However, there is another important message here, that some areas can be productive at the same time that they maintain levels of resilience above the legal compliance, which facilitates win-win scenarios in human-dominated landscapes. Faculdade de Ciências Biológicas e Ambientais FCBA/UFGD Ecologia e Conservação Campo Grande - MS Corporación para Investigaciones Biológicas Centre for Tropical Environmental and Sustainability Science College of Science and Engineering James Cook University Instituto de Biociências UNESP - Univ Estadual Paulista Rio Claro Departamento de Ecologia Departamento de Ecologia Universidade de São Paulo Centro de Engenharia Modelagem e Ciências Sociais Aplicadas Universidade Federal do ABC Ecology Evolution and Environmental Biology Columbia University Nature and Culture International Instituto de Biociências UNESP - Univ Estadual Paulista Rio Claro Departamento de Ecologia

In this paper, a procedure is developed in order to manage virtual tests using numerical simulation in order to reduce time and to optimize design before the real validation tests on wood products. This procedure in 3 steps can be used in an industrial context: (i) characterization of the material properties, (ii) construction of probabilistic density function for each parameter, (iii) Monte Carlo simulation of the structural behavior of the wood products furniture. For this purpose, experimental tests associated with digital image correlation technique were managed using 3 point bending tests easy to develop in an industrial environment. A probabilistic density function was constructed for each mechanical parameter based on the test results using the principle of maximum entropy. The simulation is managed by a FEA developed in the Matlab environment and allows a Monte-Carlo simulation in a reasonable CPU time. We can then evaluate the effect of the input data dispersions on the overall reaction of the structure. A real test is performed on a prototype product in order to confirm the simulation results and to validate the approach.

International audience; La gestion pérenne des déchets issus de l'assainissement passe par des solutions adaptées au contexte des territoires. Elle doit notamment respecter les principes de proximité dans les circuits de collecte et traitement et permettre au mieux la valorisation des déchets. L'unité de traitement des matières de vidange de Nègrepelisse répond à ces impératifs avec une solution écologique qui offre plusieurs avantages : - sobriété énergétique dans les transports induits avec un site proche des déchets à éliminer, et dans la consommation énergétique de la filière extensive de traitement mise en ½uvre - valorisation énergétique vers une filière bois-énergie locale, - intégration paysagère avec une filière qui se fond dans le paysage environnant. - durabilité du système technique et agronomique. Le travail a consisté à suivre les performances de la filière dans son ensemble : traitements des effluents, distribution sur la parcelle et son homogénéité et valorisation des eaux usées traitées par la croissance des arbres sur une période de trois saisons d'irrigation. L'objectif était de valider la filière de traitement ainsi que de tester plusieurs modalités de conduite des irrigations afin de montrer que cette filière est très performante tant en terme de finalisation du traitement de l'effluent que de valorisation par la production de bois sans impacter le milieu.

International audience; This work aims at studying the sodium periodate oxidation of 4-O-methylglucuronoxylans (MGX) in different experimental conditions for a control of the oxidation degree. A series of sodium periodate oxidation reactions were conducted at three NaIO4/xylose molar ratios: 0.05, 0.20 and 1.00. The effects of xylan molar mass, xylan concentration and reaction temperature on the reaction rate have been evaluated by UV/visible spectroscopy at 0.20 NaIO4/xylose ratio. No depolymerization is observed at 0.05 ratio while depolymerization occurs at 0.20 and is even complete at 1.00 NaIO4/xylose ratio. An increase of the reaction temperature - up to 80 degrees C - leads to an increase of the oxidation rate with no effect on the depolymerization. At high xylan concentrations, the oxidation rate increases but promotes chains aggregation.

International audience; Whereas the new stakes on lignocellulosic biomass are often demand-oriented (heat, electricity, biofuels, etc.) mainly through public policies, the new equilibrium will depend also on the supply-side. This supply has to be understood as socio-economic and environmental targets combining many topics: multi-resources (agriculture, forest, "dedicated coppices", by-products and wastes), available/potential quantities and costs, localisation, replacement/substitution effects (activities, lands), and supply-side stakeholders’ behaviours. Many initiatives have been launched to grasp those dimensions through projects (National Research Agency, French Environment and Energy Management Agency, etc.). Many figures exist on the biomass assessment aspect but they are not clear enough and not comparable due to differences in definitions, scopes, data, parameters, geographical levels, reporting units, time-scale, etc. Regarding the characterisation of biomass supply chains, evaluations are often incomplete and lack methodological references. This article aims to focus on methodological key points and barriers to overcome, in order to get a better evaluation and understanding of biomass mobilisation expected by potential users and public authorities.

BIOVERT+VBI:CPI:FRA; Cationizations of galactomannan- and xylan-type hemicelluloses were performed in a solid state, with 2,3-epoxypropyltrimethylammonium chloride (ETA) as the cationic reagent under alkaline conditions. By this method, the reaction efficiency was significantly increased for all hemicellulose types, up to 90% in the case of xylan. The consumption of reagents was reduced by a factor of ten when compared to the reaction in liquid phase, while comparable values of the degree of substitution (DS) were obtained. By reducing the number of purification steps, the consumption of solvents was limited, and high mass yields were preserved. By all aspects, this method constitutes an economical and environmental gain for the cationization reaction of hemicelluloses. Native hemicelluloses and their cationic derivatives were tested as additives to the pulp slurry in order to increase the dry strength of the paper formed. The cationization of hemicelluloses had a beneficial effect on the mechanical properties of paper, with a supplementary gain of properties compared to the unmodified polysaccharides. Cationic derivatives of a DS 0.3 gave the best results for both polysaccharides, with the galactomannan-type being more efficient than the xylan-type with a 90% increase of the burst index.

1 Bigand, Virginie Pinel, Catherine Perez, Denilson Da Silva Rataboul, Franck Huber, Patrick Petit-Conil, Michel; In this study, the cationisation of galactomannan and xylan hemicellulose types was investigated with 2,3-epoxypropyltrimethylammonium chloride (ETA) as reagent, under alkaline conditions. The degree of substitution was accurately determined by H-1 NMR spectroscopy after hydrolysis in a DCl/D2O mixture and confirmed by elemental analyses. The influence of reactional parameters on yield and DS was studied systematically and the reactivity of both polysaccharides was compared. DS values from 0.1 to 1.3 were obtained by varying reactional parameters, the most influential being the hemicellulose concentration and the epoxide amount. The corresponding mass yields varied from 40 to 80% of recovered hemicelluloses and were strongly correlated to DS values. The cationisation of xylan was studied more particularly with a D-optimal experimental design in order to identify interactions between parameters. The optimization of reactional parameters as a function of a desired DS allowed obtaining a maximal grafting rate of 48% with a DS value of 1.3 and 64% of mass yield. (C) 2011 Elsevier Ltd. All rights reserved.

International audience; Mixed interior wood panel tannin adhesive formulations were developed in which lignin is in considerable proportion, 50%, of the wood panel binder and in which no "fortification" with synthetic resins, such as isocyanates and phenol-formaldehyde resins as used in the past, was necessary to obtain results satisfying relevant standards. A low molecular mass lignin obtained industrially by formic acid/acetic acid pulping of wheat straw was used. Environment-friendly, non-toxic polymeric materials of natural origin constitute up to 94% of the total panel binder. The wood panel itself is constituted of 99.5% natural materials, the 0.5% balance being composed of glyoxal, a non-toxic and non-volatile aldehyde, and of hexamine already accepted as a non-formaldehyde-yielding compound when in presence of condensed tannin. Both particleboard and two types of plywood were shown to pass the relevant interior standards with such adhesive formulations. Moreover, the much cheaper non-purified organosolv lignin showed the same level of results as the more expensive purified type.

International audience; Maintenance procedures of different wood coating systems were studied in field exposure trials with coated balcony constructions. Maintenance coatings were applied on one half of each of the balcony parts after 18 months and assessed after 24 months of total exposure time. It was found that the opaque white coating systems were the most durable ones reaching long intervals of required maintenance. For systems with lower durability on the maintained surfaces further degradation of the coatings was prevented. Different characteristics were observed for film forming and non film forming semi-transparent varnishes. Definitions of a series of limit states for coating systems on wood were suggested including esthetical limits and three levels of durability limits. Film forming coatings can reach two durability limits, i.e. the maintenance interval and the renovation interval. For non film forming coatings there is only one limit state of coating durability where maintenance is needed. The third durability limit is related to the coated substrate, i.e. the wood component, by the onset of decay in wood.

This paper uses the cutting forces in a routing process of Aleppo pine wood to estimate the tool wear effect. The aim is to obtain further information about the tool wear effect by monitoring the variation in the cutting forces. A Kistler 9257A 3 axes Dynamometer was positioned under the workpiece to measure the cutting forces at frequencies up to 10,000 Hz. The experiments were carried out on a CNC routing machine RECORD1 of SCM. A carbide tool was used and the cutting parameters were fixed. The cutting speed was approximately 25 m/s. Dasylab software was used to capture the data. The results show a correlation between the tool wear and the computed angle ( ), between the tangential and cutting forces. In fact, the variation of ( ) is unstable in the running period and stable in the linear wear zone, included in the interval [−1.11°; −1.10°]. This study was performed as part of a development program for the Algerian wood industry, hence the selection Aleppo pine wood as the working material. FCBA Institut Technologique, FSE (Fond Social Européen), CRB (Conseil Régional de Bourgogne) and University of Boumerdes (Algeria)