Qualité du bois de six essences du maquis méditerranéen

L étude des caractéristiques physico-mécaniques du bois de six essences du maquis, ainsi qu un essai de tournage conduit par une petite entreprise spécialisée, a montré que certaines utilisations (tournage, menuiserie fine) permettent une bonne valorisation des bois du maquis, et que ceux-ci peuvent rivaliser par leur finition, leur dureté et leur bel aspect avec de nombreux bois tropicaux importés

Qualite du bois de six essences du maquis mediterraneen

16 ref.National audienc

Quality of Turkey oak (Quercus cerris,L.) wood - 1 - Soluble et insoluble proanthocyanidins

30 ref.International audienc

Comparison of thermal expansion of wood and epoxy adhesives

Epoxy-based adhesives are used both in the consolidation of decayed timbers and for new structural joints. Investigating the compatibility of wood and epoxy adhesives provides a better knowledge of the long-term behaviour of wood-epoxy joints. Besides mechanical compatibility, also temperature-related parameters are relevant in this context. The values of the thermal expansion coefficients (TEC) of two wood species (Spruce, Picea abies and Iroko, Clorophora excelsa) and four different epoxy resins have been compared using a modified test method that allows for nearly iso-hygric conditions of the wood specimens. Minor differences in TEC have been observed between wood in the transversal-to-the-grain direction and an experimental epoxy adhesive, which is considered highly compatible with wood on the basis of mechanical and ageing tests. Other commercial epoxy adhesives show greater differences in terms of TEC and a proportionally decreasing mechanical compatibility. According to these results, the evaluation of thermal properties can be considered very useful for a modelling approach to predict the long term behaviour of wood-epoxy adhesive interface

Extractives and Structural Components in Wood and Bark of Endemic Oak Quercus vulcanica Boiss

The bark and wood of an endemic oak species in Turkey, Q. vulcanica, were investigated with regard to main components, phenolics as well as extractives. About 66 % of extract free wood consists of polysaccharides, i.e. cellulose and polyoses. Heartwood was found to be rich in ellagitannins, while in bark proanthocyanidins occurred in larger amounts. Extractives soluble in cyclohexane were divided into saponifiables and neutrals. Among saponifiables saturated acids made up the majority, while sterols and nonsteroidal triterpenes were the predominating compounds of the neutral fraction

La détermination du nombre indicatif N de fibres par gramme de pâte chimique à l'aide de critères anatomiques : longueur, largeur et épaisseur de paroi

National audienc