Your search resulted in 303 documents. Displaying 25 entries per page.
The involvement of hydroxyl-radical-producing glycoprotein from the white-rot basidiomycete Ceriporiopsis subvermispora in wood decay
2009 - IRG/WP 09-10688
White-rot decay can be divided into two subtypes. One type involves the simultaneous degradation of all wood components through the formation of erosion troughs with a progressive thinning of wood cell walls. This type of decay is consistent with a model in which several polymer-degrading enzymes act on the exposed surfaces of the wood cell walls, producing progressive erosion from the lumen to th...
H Tanaka, Y Inoue, T Morikawa, S Itakura, A Enoki
Degradation of wood veneers by Fenton’s reagents: effects of low molecular weight phenolic compounds on hydrogen peroxide decay and tensile strength loss
2009 - IRG/WP 09-20400
Pine wood (Pinus sylvestris) veneers strips were incubated in acetate buffer containing hydrogen peroxide and iron to mimic mechanisms of brown rot decay and assess the degradation of cellulose through analysis of the tensile properties of the decayed wood. The tensile properties of thin wood strips treated with Fenton system reagents or precursors were determined and correlated to weight loss as ...
Yanjun Xie, R Well, Zefang Xiao, B Goodell, J Jellison, H Militz, C Mai
Chemical mediated depolymerization of cotton cellulose for the understanding of non-enzymatic fungal decay
2010 - IRG/WP 10-10731
Small, low molecular weight non-enzymatic compounds have been linked to the early stages of brown rot decay as the enzymes involved with holocellulose degradation are found to be too large to penetrate the S3 layer of intact wood cells. The most pronounced of these which were analyzed in this study are hydrogen peroxide, iron, and oxalic. The compounds related to the Fenton reaction: the combinati...
A C Steenkjær Hastrup, B Jensen, F Green III
Glutathione transferases as functional biomarkers of wood degradation?
2010 - IRG/WP 10-10735
The recent release of several fungal genome sequences allows the report of an overview of fungal glutathione transferases (GSTs) focused on their function in the wood-degrading basidiomycete Phanerochaete chrysosporium. A genomic and phylogenetic analysis of GST classes in various sequenced fungi –zygomycetes, ascomycetes and basidiomycetes- revealed some specificity in GSTs distribution, in com...
E Gelhaye, M Morel
Simulation and Investigation of Wood Degradation by Erosion Bacteria in Laboratory Experiments
2010 - IRG/WP 10-20431
A Microcosm experiment was successfully set up to establish, monitor and manipulate bacterial wood degradation under low oxygen conditions. Sound pine sticks were placed in waterlogged sediment from a heavily decayed pine pile foundation site in Amsterdam. The system was subject to different gassing treatment regimes in order to investigate the role of oxygen in the bacterial degradation process o...
J Gelbrich, E I Kretschmar, N Lamersdorf, H Militz
The Use of Micro-Tensile Testing to Assess Weathering Decay and Oxidative Degradation of Wooden Items
2010 - IRG/WP 10-20433
This paper presents a method to study the weathering performance of wooden items and to assess the oxidative degradation of wood via the Fenton reaction. Weathering resistance and photo-stability of wood was tested using pine wood (Pinus sylvestris) veneer strips measuring approximately 60 µm in thickness. The veneer strips were treated using a reactive chemical to impart surface protection. The ...
C Mai, Yanjun Xie, Zefang Xiao, P D Evans, H Militz
Degradation of Carbon-Based Preservatives by Black-stain Fungi
2010 - IRG/WP 10-30533
Some black-stain fungi are known to exhibit resistance to carbon-based preservatives. However, the cause of this resistance is unclear. The fungi may have mechanisms to tolerate these chemicals, or they may be able to degrade and detoxify them. Fungi capable of degrading carbon-based preservatives are of interest for possible bioremediation of carbon-based preservative-treated wood at the end of i...
R Stirling, P I Morris
Biological degradation of acetylated wood after 18 years in ground contact and 10 years in marine water
2010 - IRG/WP 10-40522
This paper addresses the resistance to biological degradation of acetylated wood.
Firstly, it presents results from an EN 252 test after 18 years’ exposure. The test is still running in Nordic NWPC test fields, Simlångsdalen in Sweden and Viikki in Finland. Results from this test were presented after 5 years’ exposure ( IRG/WP 97-30139), and showed that the resistance of acetylated wood wit...
P Larsson Brelid, M Westin
Lignin blocking effects on weathering process of wood plastic composites
2010 - IRG/WP 10-40529
The weathering of wood–plastic composites (WPC) causes discoloration which affects their aesthetic aspects. It has been proved that these discolorations are due to lignin degradation. Effects of blocking the susceptible structure of lignin assessed by chemical treatment such as acetylation and methylation are reported in this study. Surface chemical change of wood plastic composite (WPC) formula...
P Darabi, A Naghi karimi, S Ahmade Mirshokraie, M-F Thévenon
Utilization of thermodesorption coupled to GC-MS to study kinetics of thermodegradation of different wood species
2011 - IRG/WP 11-40559
Thermdesorption coupled to Gas Chromatography coupled to Mass Spectroscopy (TD-GC-MS) has been investigated to identify volatile degradation products generated during wood heat treatment by mild pyrolysis. For this purpose, wood samples of different softwood and hardwood species have been heat treated under nitrogen for different temperatures comprised between 180 and 230°C during 15 min. in the ...
K Candelier, M Chaouch, S Dumarçay, A Pétrissans, M Pétrissans, P Gérardin
In-situ experimental treatment and consolidation of degraded timber elements from a XIX century building
2012 - IRG/WP 12-10767
This paper presents the in situ experimental conservation work performed on three timber structural elements from a XIX century building: two floor beams and one roof beam. The palace was built in 1877 in the centre of Lisbon initially with residential purposes. It has four floors, with timber structural horizontal elements, stairs and roof beams (generally of Pinus sylvestris L.). The exterior wa...
D F Henriques, J de Brito, L Nunes
Use of Variable Pressure Scanning Electron Microscopy for in situ Observation of Degradation of Wood Surfaces during Artificial Weathering
2012 - IRG/WP 12-20489
Variable pressure scanning electron microscopy (VPSEM) is capable of observing electrically non-conductive materials like wood without the need to render the surface conductive by applying a coating of gold, platinum or carbon. Hence, there is the possibility that VPSEM could be used to non-destructively follow the structural changes occurring at wood surfaces during weathering, because specimens ...
F Hatae, Y Kataoka, M Kiguchi, H Matsunaga, J Matsumura
Utilization of thermodesorption coupled to GC-MS to characterize volatiles formation kinetics during wood thermodegradation
2012 - IRG/WP 12-40587
Identification of volatile degradation products produced during wood mild pyrolysis is important to have better insight on thermodegradation mechanisms. Previous studies have shown that thermodesorption coupled to GC-MS is an attractive tool to characterize and quantify products formed during wood thermodegradation indicating an higher susceptibility of hardwoods to thermodegradation compare to so...
K Candelier, S Dumarçay, A Pétrissans, M Pétrissans, P Kamdem, P Gérardin
Study of the use of organosolv lignin as bio-preservative of wood
2012 - IRG/WP 12-30603
The service life of wood depends on the species, use and environmental conditions of exposure. The treatment of wood protects it against degradation by xylophagous agents, enhancing the durability of material up to 10 times, and reducing the deforestation around 12.5%. In this way, the use of treatments is necessary because increases the service life of material and protect against xylophagous age...
P S B dos Santos, A Garcia, P H G de Cademartori, D A Gatto, J Labidi
Preliminary evaluation of degradation patterns in wood samples from the Yenikapı shipwrecks
2013 - IRG/WP 13-10798
The uncovering of several shipwrecks during the excavation of the Marmaray Rail Tube Tunnel Project in Istanbul provides an important opportunity to evaluate waterlogged woods buried for centuries. Identification of these woods showed that a variety of species was used in the ships. One shipwreck (a galley) from the Yenikapı Marmaray was examined using electron microscopy. The micrographs rev...
C Köse, A M Taylor
The chemistry of wood degradation by Basidiomycetes studied in a van Krevelen diagram
2013 - IRG/WP 13-10805
The atomic composition ratios of decayed wood by Basidiomycetes are mapped in a van Krevelen diagram. It is shown that the wood residue after decay is chemically reduced, rather than oxidized. A previously developed and verified theoretical model for thermal wood modification, relating atomic composition ratios to moisture sorption and fungal resistance properties has tentatively been applied to w...
W Willems, H Militz
Application of a model for the prediction of fungal degradation of thermally modified beech timber by Trametes versicolor
2013 - IRG/WP 13-40622
Colour measurement technology is found to be feasible for characterization of the property changes of thermally modified timber (TMT). In opposite to time-consuming and expensive laboratory tests a non-destructive test represents an improvement for the manufacturer of TMT. Therefore the aim of this study was to develop a method which allows sorting the different treatment intensities after the man...
Clauder, L., Richter S., Unger, W., Pfriem, A
Utilization of TG-DSC to study thermal degradation of beech and silver fir
2013 - IRG/WP 13-40628
Thermal treatment of wood is, besides other wood modification system, used to improve the decay resistance and dimensional stability. However, the chemical changes that are caused by treatment process are still difficult to quantify, characterize and control. Previous studies have shown that thermodesorption coupled to GC-MS is an attractive tool to characterize and quantify products formed during...
K Candelier, A Treu, J Dibdiakova, E Larnøy, A Petrissans, S Dumarçay, M Pétrissans, P Gérardin
Protein extraction from wood decay fungus Postia placenta
2014 - IRG/WP 14-10827
Wood decay fungi (often distinguished as white rot and brown rot) belonging to the basidiomycetes, are common inhabitants of forest litter, where they play an important role in carbon cycling. Brown rot fungi are perhaps the most important organism involved in the degradation of wood products, and of considerable economic importance. Brown rotted wood loses strength very early because of the rapid...
A Pilgård, P Arnold, K Richter
Identification of soft-rot fungi existed in the samples from the galley excavated at Yenikapi
2014 - IRG/WP 14-10833
The shipwrecks of the Middle Byzantine period were excavated during the construction of the Marmaray railway and metro station in Yenikapı between 2004 and 2012. This has become the largest investigations because of the size and the number of the shipwrecks and its associated artifacts. In the previous report, the electron micrographs of the samples revealed that a wide range in the degree of...
T Wada, C Köse, K Igarashi
Scanning Transmission X-ray Microscopy as a tool for examining chemical changes in wood cell walls due to enzymatic activity
2014 - IRG/WP 14-20556
As development of techniques for examining enzymatic activity on solid, complex biological materials, is considered to be an important factor in further development of enzyme applications and for understanding the decay of plant materials, this study explores applicability of Scanning Transmission X-ray Microscope (STXM) for determining chemical changes in enzymatically treated samples at the cell...
D Jeremic, R Goacher, R Yan, C Karunakaran, E R Master
Field performance of wood-based decking materials in the Western United States
2014 - IRG/WP 14-30645
While wood has long been used for the construction of decks and other outdoor features, a variety of wood-plastic composite (WPC) decking products have emerged over the past decade with claims of exceptional durability and low maintenance. There are relatively few long term comparative tests on these products. The performance of selected WPC decking products was compared with naturally durable we...
S Lipeh, C S Love, J J Morrell
Resistance of fungal derived pigments to ultraviolet light exposure
2014 - IRG/WP 14-30642
The potential for using fungal derived pigments as surface treatments for limiting photodegradation of wood was investigated. Extracts from Chlorociboria aeruginosa and Scytalidium cuboideum were compared with a traditional aniline dye and chromic acid treatment. Hybrid poplar sapwood samples treated with these solutions were exposed to 86.4 kj/m2 of UV radiation and assessed for lignin degradatio...
H G Beck, S Freitas, G Weber, S C Robinson, J J Morrell
Thermal durability and biodegradation of tannin lignin adhesives
2014 - IRG/WP 14-40657
Mimosa tannins and lignosulfonates were used in wood adhesives formulation to substitute resins based on formaldehyde. Mimosa tannins were mixed with either glyoxalated sodium lignosulfonates or glyoxalated ammonium lignosulfonates. The ratios of mimosa tannins and sodium lignosulfonates varied from 20% tannins to 60% tannins. The thermal durability of the adhesives were analysed by thermogravimet...
L Chupin, B Charrier, A Pizzi, F Charrier
Possible targets of wood modification in brown rot degradation
2014 - IRG/WP 14-40676
Wood modification protects wood from fungal degradation in a non-toxic manner. However, the mechanisms behind the decay resistance in modified wood are currently unknown. The aim of this study was to discuss the i) colonisation, ii) nutrient recognition, iii) transcription, iv) depolymerisation and v) hydrolysis steps in the brown rot degradation progress and explore whether they are inhibited by ...
R Ringman, A Pilgård, G Alfredsen, B Goodell, K Richter