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This dataset includesthe supplementary informationrelated to the manuscript: Authors: ŽigonJ, Pavlič M, Kibleur P, Van den BulckeJ, Petrič M, Van Acker J, Dahle S Title:Treatment of wood with atmospheric plasma discharge: Study of the treatment process, dynamic wettability and interactions with a waterborne coating

When exposed to conditions favourable for decay, bio-based building materials can be susceptible to degradation. Their ability to withstand deterioration over time (performance) depends on the intrinsic or enhanced durability of the material as well as its wetting and drying behaviour. The effect of fungicidal components in wood is known since long. Other material characteristics, such as the material’s moisture dynamics and structure, are crucial as well in prolonging a material’s service life in outdoor exposure conditions. The importance of these other material characteristics should not be underestimated, as there are many opportunities to alter a material’s moisture dynamics and to optimize the structural design of engineered wood products and bio-based insulation products. In order to do so, it is necessary to understand how different material characteristics influence the performance. In this paper, we assess the moisture dynamics of oriented strand board (OSB), porous bituminized wood fibre board (PBF), radiata pine plywood (PL), thermally modified spruce (TMT) and two wood fibre insulation boards (WF-A and WF-B). With the ‘paste test’, we assess whether these materials contain fungicidal components affecting decay. Additionally, we assess how they perform in an adapted mini-block test. We are able to show that fungicidal components are not always of major importance for the durability of a bio-based building material. Some of the assessed materials have a remarkable moisture performance. We need to work towards specific moisture performance criteria and consider including them in performance classification.

International audience; A method is presented to reconstruct quantitative material densities from X-ray CT data instead of reconstructing a linear attenuation coefficient in each voxel of the 3D volume. The polychromatic behavior of the complete system is included in the reconstruction method, as such calibration materials are not required and beam hardening artefacts are inherently eliminated from the reconstructed data.

Entandrophragma genus includes exclusively African species (10 to 12), five of which are on the IUCN Red List. Characterized by a taxonomic evolution that has resulted in an important synonymy of species names (36-3 7) and insufficient ecological knowledge, it is the richest in valuable species exploited as timber in Africa. This important exploitation is likely to compromise their durability in the absence of sustainable management. Our study is mainly based on scientific data (e.g., publications), economic data (production and export statistics) and legal data (laws and regulations); on management plans and inventory reports. The heavy industrial exploitation as artisanal does not always proceed in the respect of a validated management plan, nor of the duration of the rotations which would make it possible to reach a rate of reconstitution likely to perpetuate the resource which these species represent. Their sustainable management requires the development and respect of management measures to make their exploitation sustainable in the long term. This exploitation must be based on an adequate management of natural stands and on reforestation as well as on conservation measures. The research to be developed must focus on their growth rate (eg, in the face of climate change), the analysis of stable rings and isotopes, the evaluation of their stocks (production, biomass, carbon), their spatial distribution and molecular phylogeny, the improvement of their natural regeneration, their reproduction, phenology and anatomy, as well as the reinforcement of other relevant lines of research to guarantee the durability of these forest species.

Xylem vessel features are the most investigated anatomical traits of Angiosperm wood. They are being analyzed in ecophysiological projects aiming at understanding sap flow and vulnerability to drought stress. Since long, size, grouping and density of vessels are also used as one of the first steps in timber identification, as they can easily be observed even with a hand lens. Vessels are also known to be related to tree height. The volumetric sap flow rate is inversely related to the length of the path, so that vessels need to widen at lower parts of the tree and taper towards the higher parts to assure optimal transport and a stable hydraulic resistance with progressing growth in height. Vessels are expected to narrow from roots to stem and further to the branches and the petioles. Accordingly it is also predictable that vessel features on pith-to-bark profiles are a proxy for height growth for individual trees. Since the functional groups of species of a tropical rainforest are based on height grow rate (related to light needs), it is expected that pith-to-bark profiles of vessels reveal information on temperament of the species. A methodology has been developed to establish pith-to-bark profiles of vessel features, based on long microtomic sections, image analysis and machine learning. Entandrophragma was used as a model genus. The differences between the four most common species of this genus have been explored. Wilcoxon signed rank test indicate that the difference in mean vessel size is significant between every species combination except between Entandrophragma candollei and Entandrophragma cylindricum. Interesting to note is the large vessel size range possible for Entandrophragma utile. Currently, pith-to-bark vessel trends are constructed that could help explaining difference in growth strategy. The approach offers appealing perspectives to find a formal way for sub setting tree species into functional groups and develop indexes for growing conditions of forest sites.

Because of the quality of their wood and their many traditional uses, species of the Entandrophragma genus are being intensively logged, and this is likely to compromise their survival unless sustainable management is introduced. This study reviews the current status of the five main commercial Entandrophragma species: Entandrophragma angolense, E. congo-lense (often confused with E. angolense), E. candollei, E. cylindricum and E. utile. We suggest directions for research to improve sustainable management strategies for this genus. The study draws mainly on published scientific data, economic data (production and export sta-tistics) and on relevant laws and regulations, but also on existing management plans and inventory reports. Although these species are reported as vulnerable on the IUCN Red List, knowledge on their management is still patchy. Industrial and artisanal logging is intensive and does not always follow a validated management plan or abide by the minimum rotation period, both of which would help to ensure the renewal of these resources. Managing them to ensure that logging is sustainable in the long term requires management measures to be developed and complied with. Sustainable use has to be based on appropriate management of natural stands and on reforestation and conservation measures. Research studies to be developed should encompass the growth rates of the species in the light of the changing climate, assessments of stocks (timber, biomass and carbon), updates of their spatial distribution, improvements to natural regeneration, reproduction processes and the anatomical and technical properties of each species. All these research topics are necessary to ensure the permanence of these Entandrophragma species., SCOPUS: ar.j, info:eu-repo/semantics/published

Drying is a fundamental step in solid wood processing, yet it is very challenging because of potential drying defects negatively affecting the final product quality. Successful kiln drying depends largely on the diffusivity and permeability of the wood species. Despite many research efforts, predicting kiln-drying schedules for a given wood species is not yet possible. The main reason is that important spatio-temporal variables such as moisture and temperature gradients, and wood anatomical features are considered insufficiently in the predictive modelling framework. We expect that monitoring and controlling drying up to the limit states can be used for any wood species. To understand the influence of parameters determining these limit states we developed an experimental measurement set-up. This set-up allows real-time monitoring of local moisture content gradient inferred from the electrical resistance gradient, wood temperature gradient and average moisture loss in function of time for any wood species. The obtained data is linked directly to the wood anatomical structure on the end grain, the occurrence of cracks and the transversal shrinkage. This methodology enables to unveil interrelationships between physical parameters and changes of the wood anatomical structure. We present a proof-of-concept with basralocus (Dicorynia guianensis).