Your search resulted in 391 documents. Displaying 25 entries per page.
Chemical defense of trees and wood natural durability: from protection to valorization
2019 - IRG/WP 19-10943
Natural durability of wood is defined as “the inherent resistance of wood against various wood-destroying organisms” (European standard EN 350-1). This property is due in particular to heartwood extractives. However, the wood natural durability is included in a wider defense system, and other organs such as bark and roots also host protective compounds. Studying the mechanisms on which global ...
E Houel, D Stien, N Amusant
Determining the natural durability on xylarium samples: mini-block test, wood powder and chemical profiling
2019 - IRG/WP 19-10944
Xylaria, or wood collections, can be considered sleeping beauties in terms of wood technological and biological output. In this study we focus on determining the natural durability of xylarium specimens from the Federal Xylarium in the Royal Museum for Central Africa. The Federal Xylarium contains over 80,000 specimens, covering more than 13,000 species, mainly from Central Africa. These specimens...
V Deklerck, L De Ligne, J Van den Bulcke, E Espinoza, H Beeckman, J Van Acker
Coula edulis baill an unknown wood species as an alternative to the main durable wood species used in Gabon
2019 - IRG/WP 19-10945
The Congo Basin hosts an exceptional biodiversity of trees, flora and fauna. However, the immense natural heritage of the forests in this area is increasingly threatened by many anthropogenic factors, due to selective exploitation of certain wood species. In Gabon, whose ecosystem is representative of this area, the forest represents nearly 80% of the national territory. Only a minority of wood sp...
C S A Bopenga Bopenga, S Dumarçay, P Edou Engonga, P Gerardin
Chemical composition, antitermite and antifungal activity of Dacryodes edulis oleoresin
2019 - IRG/WP 19-20653
Damages to wood structures and other cellulosic materials caused by wood destroying insects and fungi are estimated to several billions of dollars each year in the world. Among these, termites are considered as one of the most economically important pests for wooden structures. In the past, several wood protection chemicals like CCA, creosote, lindane or pentachlorophenol have been used. However, ...
W F Bedounguindzi, K Candelier, P E Engonga, Se Dumarcay, M-F Thevenon, P Gerardin
Chemical Analysis of Southern Pine Pole Stubs Sixty Months Following Treatment with a Methylisothiocyanate-Based Solid Fumigant Stick
2019 - IRG/WP 19-30740
Methylisothiocyanate-based fumigants have been commercially used in the United States for over 35 years to control internal decay in utility poles and other wooden structures with little technological advancement. The most recently commercialized methylisothiocyanate-based fumigant is chemically known as dazomet. Dazomet is a free-flowing powder or granule that decomposes in the presence of mois...
D J Herdman, T Pope, R R Browning
Using X-ray scattering to elucidate the mechanisms behind the moisture and fungal decay resistance of epoxybutene modified wood
2019 - IRG/WP 19-40854
Chemical modification of the hydroxyl groups of wood can improve the properties of wood by providing moisture and biological resistance, as well as dimensional stability. Southern pine solid wood was chemically modified to various weight percentage gains (WPG) with epoxybutene (EpB, 8%-38% WPG). After modification, specimens were extracted with a toluene: ethanol (2:1) solution for 2 hours or wate...
R E Ibach, N Plaza
Dimensional stability and decay resistance of montmorillonite- furfuryl alcohol modified wood
2019 - IRG/WP 19-40856
Poplar (Populus cathayana) wood was impregnated successively by organo-montmorillonite (OMMT; in concentration of 2%) and furfuryl alcohol (FA, in concentrations of 15%, 30% and 50%) in a two-step method to prepare OMMT-FA modified wood. The modified wood samples were characterized using X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). Moreover, wood physical and a...
L Zhang, J Cao
Mineralization of European oak with various ionic salt solutions to achieve an in situ precipitation of calcium oxalate
2019 - IRG/WP 19-40861
Thin specimens of European oak (Quercus spp.) with the dimensions of 4 × 20 × 50 mm3 were treated with various aqueous ionic salt solutions of calcium chloride, potassium oxalate and calcium acetate. Additionally, the oak was treated with combinations of calcium chloride and potassium oxalate, as well as calcium acetate and potassium oxalate with the aim to precipitate in situ the water insolubl...
T Franke, T S Volkmer
An overview of recent studies involving the thermal modification of hardwood species
2019 - IRG/WP 19-40869
This paper outlines recent activities related to the thermal modification of hardwood species, and particularly to tropical hardwood species. Timber demand is ever increasing, but this is being limited by the necessity to protect virgin forest stands. As such, the majority of supply of popular species is being met from juvenile short rotation stands. The limited age from these stands often plays a...
D Jones, M Gaff, F Kacik
Charring of Norway spruce wood surface – an alternative surface modification technique?
2019 - IRG/WP 19-40870
Charring is an old wood surface treatment technique, mainly performed on wooden façade elements with the aesthetical aims, but also with the purpose of protection. This flame treatment method can be grouped into heat treatment processes. Below the top charred layer of damaged wood there is a layer which is during flame treatment exposed to high temperatures in anoxic or semi-anoxic conditions. Th...
M Petric, M Pavlic, J Zigon
Improvement of wood decay and termite durability resulting from combined treatments based on borax/phenol-formaldehyde impregnation followed by thermal modification
2019 - IRG/WP 19-40871
This study determined the factors influencing the boron content after leaching of pine blocks impregnated with aqueous solution of phenol-formaldehyde (PF) resin with or without borax and subjected to heat treatment by response surface methodology. An experimental design permits to analyze the effects of heat treatment temperature (150, 185 and 220°C), curing time (5, 12, 5 and 20 hours), resin c...
S Salman, M-F Thevenon, A Petrissans, S Dumarcay, P Gerardin
Towards better integration of wood protection in the forestry wood industry chain - a case study on hybrid poplar
2019 - IRG/WP 19-50359
Wood and wood products are limited in service life as in the forest ecosystem trees at end of their life are degraded to re-enter the bio-geochemical cycle. Humans can select wood species with a level of natural durability fit for an envisaged end use. Mainly those applications that require a long service life under conditions that are similar to those at soil level in a forest ecosystem have been...
J Van Acker
Chemical composition and performances of slow pyrolysis by-product from sugarcane bagasse for wood protection
2020 - IRG/WP 20-30752
Pyrolysis distillate or bio-oil, a by-product of biomasses’ slow pyrolysis in the char-making process, has been traditionally used as bio-pesticides by Asian farmers. Due to its large composition of bio-active chemicals, bio-oil obtained from various biomass has become of interest in many applications, including wood protectants. This study aims to characterize the chemical composition of bio-oi...
F D Boer, M-F Thévenon, J-M Commandre, M Fournier
Investigations into the use of Maleic Anhydride/Sodium Hypophosphite as a Wood Modification Process
2020 - IRG/WP 20-40891
The formation of crosslinked bonds between wood constituents is believed to be an effective way to stabilize wood against wet conditions. The possibility to use maleic anhydride (MA) combined with sodium hypophosphite (SHP) as crosslinking agents was studied, using Scots pine sapwood and a model compound. The modified wood showed weight gain and bulking effect after treatment and subsequent Soxhle...
I Kim, D Jones, O Karlsson, D Sandberg, O N Antzutkin, F Ullah Shah
Elucidation of reactive sites of wood modified with acetic anhydride: Insights from density functional theory calculations
2020 - IRG/WP 20-40892
Density functional theory (DFT) was employed to investigate the interaction of cellulose and lignin with acetic anhydride for explaining the wood modification process. Atoms in molecules (AIM) and reduced density gradient (RDG) along with non-covalent interaction (NCI) plots were used to analyse the intermolecular bonding characteristics. Cellulose was modelled with a cellobiose unit (dimer of glu...
V Ponnuchamy, A Sandak, J Sandak, R Herrera Diaz
Evaluation of chemical densification of three hardwood species through in-situ electron beam polymerization
2020 - IRG/WP 20-40893
Hardwoods are the most suitable species for wood flooring for their appearance as well as their hardness. Yet, improving hardness can provide substantial benefit for the wood flooring market. Chemical densification of wood and in-situ polymerization through electron beam technology was chosen to increase hardness of three hardwoods (Yellow birch (YB) (Betula alleghaniensis Britt.), Sugar maple (SM...
J Triquet, P Blanchet, V Landry
Comprehensive protection of timber in seawater
2020 - IRG/WP 20-10970
The hazard of wood in seawater can be divided into two areas: Below the water level, shipworm (Teredo navalis) and gribble (Limnoria lignorum) can attack non-resistant or insufficiently protected wood; above the water level, there is a risk by wood-destroying fungi and, to a lesser extent, insects. In a national project funded by the Deutsche Bundesstiftung Umwelt (DBU, German Federal Environmenta...
E Melcher, J Müller, T Huckfeldt
A summary of decay performance with citric acid and sorbitol modification
2020 - IRG/WP 20-40898
Application of wood-based products as construction materials is one piece of the big puzzle to mitigate climate change. Wood is susceptible to biological deterioration. Environmentally motivated legislation is making the use of biocides less attractive from a commercial perspective. Ideally, a wood modification technology should be of low cost, water based and make use of thermal curing. This rese...
G Alfredsen, E Larnøy, G Beck, J Biørnstad, L R Gobakken, C A S Hill, A Treu
Macro biological degradation of wood treated with sorbitol and citric acid – first results from marine environment and termite exposure
2020 - IRG/WP 20-40901
Most European wood species are rapidly and severely degraded in termite-infested areas and the marine environment. There is a need for new solutions, especially in the marine environment, since we lack wood preservatives approved for marine applications in Europe. Several wood modification systems show high resistance against both marine borers and subterranean termites. However, the existing comm...
A Treu, L Nunes, E Larnøy
The influence of chemical compounds on wood cell wall to surface cracks
2020 - IRG/WP 20-40908
Degradation due to cracking and dimensional changes caused by drying, have a significantly negative impact on the preservation and durability of wood. Therefore, the prevention of surface cracking, which tends to occur during the drying process, is vital. High temperature set drying is one of the most effective methods for preventing wood surface cracking. It begins with softening the wood at a hi...
R Suzuki, Y Mori, K Yoshihiro, K Yamashita, M Kiguchi
NewSiest-Enhancement of UV stability of thermally modified wood through envelope impregnation with nanobased stabilisers
2020 - IRG/WP 20-40909
Thermal modification is a process which improves the properties of wood, resulting in a material that can be disposed at the end of the product life cycle without presenting an environmental hazard. Thermally modified wood retains as a natural product and the grain, original colour variances and characteristics of wood are still present. However, exposure to daylight causes brightening or greying ...
K Srinivasa, M Petrič
Enhancing the durability of low durability Eucalyptus plantation species: a review of strategies
2020 - IRG/WP 20-40910
Eucalyptus species native to Australia have shown excellent growth rates, good physical properties and resistance to diseases. As a result, they are widely planted globally for a variety of uses. One negative aspect of many of these faster growing species is that they have a high percentage of low durability heartwood that resists preservative treatment. In Australia, large plantations of these sp...
K C Wood, J J Morrell, W Leggate
Plasma treatment of wood - a review of 15 years of research in Göttingen
2021 - IRG/WP 21-40913
Wood is an important renewable resource and can be found omnipresent in everyday life. Its natural properties offer numerous advantages regarding physical, mechanical but also aesthetic aspects, but also challenges that one has to address with various modification methods.
Driven by the desire to promote the use of promising new technologies using plasmas, there has been a close research network ...
P Sauerbier, R Köhler, G Avramidis, W Viöl, H Militz
Influence of weathering on surface roughness of thermally modified wood
2021 - IRG/WP 21-40915
Thermally modified wood is exposed to weathering similarly as other wood-based building materials. It has been reported that if thermally modified wood is exposed to weathering, its moisture performance might decrease fairly fast. The aim of this study was to determine whether this phenomenon is associated with crack formations or roughness. Norway spruce, thermally modified spruce, wax-treated th...
E Kerzic, B Lesar, M Humar
The iron reduction by chemical components of wood blocks decayed by wood rotting fungi
2021 - IRG/WP 21-10979
Brown-rot fungi, a group of wood rotting fungi, is well known to be one of major microorganisms that cause the deterioration of wooden buildings in Japan and have been considered to use chelator-mediated Fenton (CMF) reaction in concert with hydrolytic and redox enzymes for degradation of wood cell wall. CMF can be described as a non-enzymatic degradation system that utilizes hydroxyl radicals pro...
R R Kondo, Y Horikawa, K Ando, B Goodell, M Yoshida